Chris Field

All Publications

• Climate impacts of digital use supply chains Environmental Research: Climate Shi, L., Brandt, A., Iancu, D., Mach, K. J., Field, C., Cho, M., Ng, M., Chey, K., Ram, N., Robinson, T., Reeves, B. 2024; 3 (1)

  View details for DOI 10.1088/2752-5295/ad22eb

• Enabling pathways for sustainable livelihoods in planned relocation NATURE CLIMATE CHANGE Bower, E. R., Badamikar, A., Wong-Parodi, G., Field, C. B. 2023

  View details for DOI 10.1038/s41558-023-01753-x

  View details for Web of Science ID 001037310500001

• Long-term elevated precipitation induces grassland soil carbon loss via microbe-plant-soil interplay. Global change biology Wang, M., Sun, X., Cao, B., Chiariello, N. R., Docherty, K. M., Field, C. B., Gao, Q., Gutknecht, J. L., Guo, X., He, G., Hungate, B. A., Lei, J., Niboyet, A., Le Roux, X., Shi, Z., Shu, W., Yuan, M., Zhou, J., Yang, Y. 2023

  Abstract

  Global climate models predict that the frequency and intensity of precipitation events will increase in many regions across the world. However, the biosphere-climate feedback to elevated precipitation (eP) remains elusive. Here, we report a study on one of the longest field experiments assessing the effects of eP, alone or in combination with other climate change drivers such as elevated CO2 (eCO2 ), warming and nitrogen deposition. Soil total carbon (C) decreased after a decade of eP treatment, while plant root production decreased after 2 years. To explain this asynchrony, we found that the relative abundances of fungal genes associated with chitin and protein degradation increased and were positively correlated with bacteriophage genes, suggesting a potential viral shunt in C degradation. In addition, eP increased the relative abundances of microbial stress tolerance genes, which are essential for coping with environmental stressors. Microbial responses to eP were phylogenetically conserved. The effects of eP on soil total C, root production, and microbes were interactively affected by eCO2 . Collectively, we demonstrate that long-term eP induces soil C loss, owing to changes in microbial community composition, functional traits, root production, and soil moisture. Our study unveils an important, previously unknown biosphere-climate feedback in Mediterranean-type water-limited ecosystems, namely how eP induces soil C loss via microbe-plant-soil interplay.

  View details for DOI 10.1111/gcb.16811

  View details for PubMedID 37317051

• The magnitude and pace of photosynthetic recovery after wildfire in California ecosystems. Proceedings of the National Academy of Sciences of the United States of America Hemes, K. S., Norlen, C. A., Wang, J. A., Goulden, M. L., Field, C. B. 2023; 120 (15): e2201954120

  Abstract

  Wildfire modifies the short- and long-term exchange of carbon between terrestrial ecosystems and the atmosphere, with impacts on ecosystem services such as carbon uptake. Dry western US forests historically experienced low-intensity, frequent fires, with patches across the landscape occupying different points in the fire-recovery trajectory. Contemporary perturbations, such as recent severe fires in California, could shift the historic stand-age distribution and impact the legacy of carbon uptake on the landscape. Here, we combine flux measurements of gross primary production (GPP) and chronosequence analysis using satellite remote sensing to investigate how the last century of fires in California impacted the dynamics of ecosystem carbon uptake on the fire-affected landscape. A GPP recovery trajectory curve of more than five thousand fires in forest ecosystems since 1919 indicated that fire reduced GPP by [Formula: see text] g C m[Formula: see text] y[Formula: see text]([Formula: see text]) in the first year after fire, with average recovery to prefire conditions after [Formula: see text] y. The largest fires in forested ecosystems reduced GPP by [Formula: see text] g C m[Formula: see text] y[Formula: see text] (n = 401) and took more than two decades to recover. Recent increases in fire severity and recovery time have led to nearly [Formula: see text] MMT CO[Formula: see text] (3-y rolling mean) in cumulative forgone carbon uptake due to the legacy of fires on the landscape, complicating the challenge of maintaining California's natural and working lands as a net carbon sink. Understanding these changes is paramount to weighing the costs and benefits associated with fuels management and ecosystem management for climate change mitigation.

  View details for DOI 10.1073/pnas.2201954120

  View details for PubMedID 37011220

• Low-elevation conifers in California's Sierra Nevada are out of equilibrium with climate. PNAS nexus Hill, A. P., Nolan, C. J., Hemes, K. S., Cambron, T. W., Field, C. B. 2023; 2 (2): pgad004

  Abstract

  Since the 1930s, California's Sierra Nevada has warmed by an average of 1.2 ∘ C. Warming directly primes forests for easier wildfire ignition, but the change in climate also affects vegetation species composition. Different types of vegetation support unique fire regimes with distinct probabilities of catastrophic wildfire, and anticipating vegetation transitions is an important but undervalued component of long-term wildfire management and adaptation. Vegetation transitions are more likely where the climate has become unsuitable but the species composition remains static. This vegetation climate mismatch (VCM) can result in vegetation conversions, particularly after a disturbance like wildfire. Here we produce estimates of VCM within conifer-dominated forests in the Sierra Nevada. Observations from the 1930s Wieslander Survey provide a foundation for characterizing the historical relationship between Sierra Nevada vegetation and climate before the onset of recent, rapid climate change. Based on comparing the historical climatic niche to the modern distribution of conifers and climate, ∼19.5% of modern Sierra Nevada coniferous forests are experiencing VCM, 95% of which is below an elevation of 2356 m. We found that these VCM estimates carry empirical consequences: likelihood of type-conversion increased by 9.2% for every 10% decrease in habitat suitability. Maps of Sierra Nevada VCM can help guide long-term land management decisions by distinguishing areas likely to transition from those expected to remain stable in the near future. This can help direct limited resources to their most effective uses-whether it be protecting land or managing vegetation transitions-in the effort to maintain biodiversity, ecosystem services, and public health in the Sierra Nevada.

  View details for DOI 10.1093/pnasnexus/pgad004

  View details for PubMedID 36874277

  View details for PubMedCentralID PMC9976749

• Enhancing the review process in global environmental assessments: The case of the IPCC ENVIRONMENTAL SCIENCE & POLICY Palutikof, J. P., Boulter, S. L., Field, C. B., Mach, K. J., Manning, M. R., Mastrandrea, M. D., Meyer, L., Minx, J. C., Pereira, J. J., Plattner, G., Ribeiro, S., Sokona, Y., Stadler, F., Swart, R. 2023; 139: 118-129

  View details for DOI 10.1016/j.envsci.2022.10.012

  View details for Web of Science ID 000895282300001

• Long-term nitrogen deposition enhances microbial capacities in soil carbon stabilization but reduces network complexity. Microbiome Ma, X., Wang, T., Shi, Z., Chiariello, N. R., Docherty, K., Field, C. B., Gutknecht, J., Gao, Q., Gu, Y., Guo, X., Hungate, B. A., Lei, J., Niboyet, A., Le Roux, X., Yuan, M., Yuan, T., Zhou, J., Yang, Y. 2022; 10 (1): 112

  Abstract

  BACKGROUND: Anthropogenic activities have increased the inputs of atmospheric reactive nitrogen (N) into terrestrial ecosystems, affecting soil carbon stability and microbial communities. Previous studies have primarily examined the effects of nitrogen deposition on microbial taxonomy, enzymatic activities, and functional processes. Here, we examined various functional traits of soil microbial communities and how these traits are interrelated in a Mediterranean-type grassland administrated with 14 years of 7 g m-2 year-1 of N amendment, based on estimated atmospheric N deposition in areas within California, USA, by the end of the twenty-first century.RESULTS: Soil microbial communities were significantly altered by N deposition. Consistent with higher aboveground plant biomass and litter, fast-growing bacteria, assessed by abundance-weighted average rRNA operon copy number, were favored in N deposited soils. The relative abundances of genes associated with labile carbon (C) degradation (e.g., amyA and cda) were also increased. In contrast, the relative abundances of functional genes associated with the degradation of more recalcitrant C (e.g., mannanase and chitinase) were either unchanged or decreased. Compared with the ambient control, N deposition significantly reduced network complexity, such as average degree and connectedness. The network for N deposited samples contained only genes associated with C degradation, suggesting that C degradation genes became more intensely connected under N deposition.CONCLUSIONS: We propose a conceptual model to summarize the mechanisms of how changes in above- and belowground ecosystems by long-term N deposition collectively lead to more soil C accumulation. Video Abstract.

  View details for DOI 10.1186/s40168-022-01309-9

  View details for PubMedID 35902889

• Atmospheric variability contributes to increasing wildfire weather but not as much as global warming. Proceedings of the National Academy of Sciences of the United States of America Diffenbaugh, N. S., Konings, A. G., Field, C. B. 2021; 118 (46)

  View details for DOI 10.1073/pnas.2117876118

  View details for PubMedID 34764227

• Forest fires and climate-induced tree range shifts in the western US. Nature communications Hill, A. P., Field, C. B. 2021; 12 (1): 6583

  Abstract

  Due to climate change, plant populations experience environmental conditions to which they are not adapted. Our understanding of the next century's vegetation geography depends on the distance, direction, and rate at which plant distributions shift in response to a changing climate. In this study we test the sensitivity of tree range shifts (measured as the difference between seedling and mature tree ranges in climate space) to wildfire occurrence, using 74,069 Forest Inventory Analysis plots across nine states in the western United States. Wildfire significantly increased the seedling-only range displacement for 2 of the 8 tree species in which seedling-only plots were displaced from tree-plus-seedling plots in the same direction with and without recent fire. The direction of climatic displacement was consistent with that expected for warmer and drier conditions. The greater seedling-only range displacement observed across burned plots suggests that fire can accelerate climate-related range shifts and that fire and fire management will play a role in the rate of vegetation redistribution in response to climate change.

  View details for DOI 10.1038/s41467-021-26838-z

  View details for PubMedID 34782624

• The limiting factors and regulatory processes that control the environmental responses of C3, C3-C4 intermediate, and C4 photosynthesis. Oecologia Johnson, J. E., Field, C. B., Berry, J. A. 2021

  Abstract

  Here, we describe a model of C3, C3-C4 intermediate, and C4 photosynthesis that is designed to facilitate quantitative analysis of physiological measurements. The model relates the factors limiting electron transport and carbon metabolism, the regulatory processes that coordinate these metabolic domains, and the responses to light, carbon dioxide, and temperature. It has three unique features. First, mechanistic expressions describe how the cytochrome b6f complex controls electron transport in mesophyll and bundle sheath chloroplasts. Second, the coupling between the mesophyll and bundle sheath expressions represents how feedback regulation of Cyt b6f coordinates electron transport and carbon metabolism. Third, the temperature sensitivity of Cyt b6f is differentiated from that of the coupling between NADPH, Fd, and ATP production. Using this model, we present simulations demonstrating that the light dependence of the carbon dioxide compensation point in C3-C4 leaves can be explained by co-occurrence of light saturation in the mesophyll and light limitation in the bundle sheath. We also present inversions demonstrating that population-level variation in the carbon dioxide compensation point in a Type I C3-C4 plant, Flaveria chloraefolia, can be explained by variable allocation of photosynthetic capacity to the bundle sheath. These results suggest that Type I C3-C4 intermediate plants adjust pigment and protein distributions to optimize the glycine shuttle under different light and temperature regimes, and that the malate and aspartate shuttles may have originally functioned to smooth out the energy supply and demand associated with the glycine shuttle. This model has a wide range of potential applications to physiological, ecological, and evolutionary questions.

  View details for DOI 10.1007/s00442-021-05062-y

  View details for PubMedID 34714387

• Bob Scholes: Multifaceted scientist with a genius for synthesis. Proceedings of the National Academy of Sciences of the United States of America Archibald, S., Field, C. B. 2021; 118 (36)

  View details for DOI 10.1073/pnas.2113299118

  View details for PubMedID 34475222

  View details for PubMedCentralID PMC8433541

• An Ecosystem-Scale Flux Measurement Strategy to Assess Natural Climate Solutions. Environmental science & technology Hemes, K. S., Runkle, B. R., Novick, K. A., Baldocchi, D. D., Field, C. B. 2021

  Abstract

  Eddy covariance measurement systems provide direct observation of the exchange of greenhouse gases between ecosystems and the atmosphere, but have only occasionally been intentionally applied to quantify the carbon dynamics associated with specific climate mitigation strategies. Natural climate solutions (NCS) harness the photosynthetic power of ecosystems to avoid emissions and remove atmospheric carbon dioxide (CO2), sequestering it in biological carbon pools. In this perspective, we aim to determine which kinds of NCS strategies are most suitable for ecosystem-scale flux measurements and how these measurements should be deployed for diverse NCS scales and goals. We find that ecosystem-scale flux measurements bring unique value when assessing NCS strategies characterized by inaccessible and hard-to-observe carbon pool changes, important non-CO2 greenhouse gas fluxes, the potential for biophysical impacts, or dynamic successional changes. We propose three deployment types for ecosystem-scale flux measurements at various NCS scales to constrain wide uncertainties and chart a workable path forward: "pilot", "upscale", and "monitor". Together, the integration of ecosystem-scale flux measurements by the NCS community and the prioritization of NCS measurements by the flux community, have the potential to improve accounting in ways that capture the net impacts, unintended feedbacks, and on-the-ground specifics of a wide range of emerging NCS strategies.

  View details for DOI 10.1021/acs.est.0c06421

  View details for PubMedID 33660506

• Long-term warming in a Mediterranean-type grassland affects soil bacterial functional potential but not bacterial taxonomic composition. NPJ biofilms and microbiomes Gao, Y., Ding, J., Yuan, M., Chiariello, N., Docherty, K., Field, C., Gao, Q., Gu, B., Gutknecht, J., Hungate, B. A., Le Roux, X., Niboyet, A., Qi, Q., Shi, Z., Zhou, J., Yang, Y. 2021; 7 (1): 17

  Abstract

  Climate warming is known to impact ecosystem composition and functioning. However, it remains largely unclear how soil microbial communities respond to long-term, moderate warming. In this study, we used Illumina sequencing and microarrays (GeoChip 5.0) to analyze taxonomic and functional gene compositions of the soil microbial community after 14 years of warming (at 0.8-1.0°C for 10 years and then 1.5-2.0°C for 4 years) in a Californian grassland. Long-term warming had no detectable effect on the taxonomic composition of soil bacterial community, nor on any plant or abiotic soil variables. In contrast, functional gene compositions differed between warming and control for bacterial, archaeal, and fungal communities. Functional genes associated with labile carbon (C) degradation increased in relative abundance in the warming treatment, whereas those associated with recalcitrant C degradation decreased. A number of functional genes associated with nitrogen (N) cycling (e.g., denitrifying genes encoding nitrate-, nitrite-, and nitrous oxidereductases) decreased, whereas nifH gene encoding nitrogenase increased in the warming treatment. These results suggest that microbial functional potentials are more sensitive to long-term moderate warming than the taxonomic composition of microbial community.

  View details for DOI 10.1038/s41522-021-00187-7

  View details for PubMedID 33558544

• Routing algorithms as tools for integrating social distancing with emergency evacuation. Scientific reports Tsai, Y., Rastogi, C., Kitanidis, P. K., Field, C. B. 2021; 11 (1): 19623

  Abstract

  One of the lessons from the COVID-19 pandemic is the importance of social distancing, even in challenging circumstances such as pre-hurricane evacuation. To explore the implications of integrating social distancing with evacuation operations, we describe this evacuation process as a Capacitated Vehicle Routing Problem (CVRP) and solve it using a DNN (Deep Neural Network)-based solution (Deep Reinforcement Learning) and a non-DNN solution (Sweep Algorithm). A central question is whether Deep Reinforcement Learning provides sufficient extra routing efficiency to accommodate increased social distancing in a time-constrained evacuation operation. We found that, in comparison to the Sweep Algorithm, Deep Reinforcement Learning can provide decision-makers with more efficient routing. However, the evacuation time saved by Deep Reinforcement Learning does not come close to compensating for the extra time required for social distancing, and its advantage disappears as the emergency vehicle capacity approaches the number of people per household.

  View details for DOI 10.1038/s41598-021-98643-z

  View details for PubMedID 34608178

• Directions for Research on Climate and Conflict. Earth's future Mach, K. J., Adger, W. N., Buhaug, H., Burke, M., Fearon, J. D., Field, C. B., Hendrix, C. S., Kraan, C. M., Maystadt, J., O'Loughlin, J., Roessler, P., Scheffran, J., Schultz, K. A., von Uexkull, N. 2020; 8 (7): e2020EF001532

  Abstract

  The potential links between climate and conflict are well studied, yet disagreement about the specific mechanisms and their significance for societies persists. Here, we build on assessment of the relationship between climate and organized armed conflict to define crosscutting priorities for future directions of research. They include (1) deepening insight into climate-conflict linkages and conditions under which they manifest, (2) ambitiously integrating research designs, (3) systematically exploring future risks and response options, responsive to ongoing decision-making, and (4) evaluating the effectiveness of interventions to manage climate-conflict links. The implications of this expanding scientific domain unfold in real time.

  View details for DOI 10.1029/2020EF001532

  View details for PubMedID 32715014

• Landscape scale variation in the hydrologic niche of California coast redwood ECOGRAPHY Francis, E. J., Asner, G. P., Mach, K. J., Field, C. B. 2020

  View details for DOI 10.1111/ecog.05080

  View details for Web of Science ID 000541865500001

• Climate change and ecosystems: threats, opportunities and solutions. Philosophical transactions of the Royal Society of London. Series B, Biological sciences Malhi, Y., Franklin, J., Seddon, N., Solan, M., Turner, M. G., Field, C. B., Knowlton, N. 2020; 375 (1794): 20190104

  Abstract

  The rapid anthropogenic climate change that is being experienced in the early twenty-first century is intimately entwined with the health and functioning of the biosphere. Climate change is impacting ecosystems through changes in mean conditions and in climate variability, coupled with other associated changes such as increased ocean acidification and atmospheric carbon dioxide concentrations. It also interacts with other pressures on ecosystems, including degradation, defaunation and fragmentation. There is a need to understand the ecological dynamics of these climate impacts, to identify hotspots of vulnerability and resilience and to identify management interventions that may assist biosphere resilience to climate change. At the same time, ecosystems can also assist in the mitigation of, and adaptation to, climate change. The mechanisms, potential and limits of such nature-based solutions to climate change need to be explored and quantified. This paper introduces a thematic issue dedicated to the interaction between climate change and the biosphere. It explores novel perspectives on how ecosystems respond to climate change, how ecosystem resilience can be enhanced and how ecosystems can assist in addressing the challenge of a changing climate. It draws on a Royal Society-National Academy of Sciences Forum held in Washington DC in November 2018, where these themes and issues were discussed. We conclude by identifying some priorities for academic research and practical implementation, in order to maximize the potential for maintaining a diverse, resilient and well-functioning biosphere under the challenging conditions of the twenty-first century. This article is part of the theme issue 'Climate change and ecosystems: threats, opportunities and solutions'.

  View details for DOI 10.1098/rstb.2019.0104

  View details for PubMedID 31983329

  View details for PubMedCentralID PMC7017779

• Fire history and plant community composition outweigh decadal multi-factor global change as drivers of microbial composition in an annual grassland JOURNAL OF ECOLOGY Qin, C., Zhu, K., Chiariello, N. R., Field, C. B., Peay, K. G. 2020; 108 (2): 611–25

  View details for DOI 10.1111/1365-2745.13284

  View details for Web of Science ID 000520163600018

• Fire affects the taxonomic and functional composition of soil microbial communities, with cascading effects on grassland ecosystem functioning GLOBAL CHANGE BIOLOGY Yang, S., Zheng, Q., Yang, Y., Yuan, M., Ma, X., Chiariello, N. R., Docherty, K. M., Field, C. B., Gutknecht, J. M., Hungate, B. A., Niboyet, A., Le Roux, X., Zhou, J. 2020; 26 (2): 431–42

  Abstract

  Fire is a crucial event regulating the structure and functioning of many ecosystems. Yet few studies have focused on how fire affects taxonomic and functional diversities of soil microbial communities, along with changes in plant communities and soil carbon (C) and nitrogen (N) dynamics. Here, we analyze these effects in a grassland ecosystem 9 months after an experimental fire at the Jasper Ridge Global Change Experiment site in California, USA. Fire altered soil microbial communities considerably, with community assembly process analysis showing that environmental selection pressure was higher in burned sites. However, a small subset of highly connected taxa was able to withstand the disturbance. In addition, fire decreased the relative abundances of most functional genes associated with C degradation and N cycling, implicating a slowdown of microbial processes linked to soil C and N dynamics. In contrast, fire stimulated above- and belowground plant growth, likely enhancing plant-microbe competition for soil inorganic N, which was reduced by a factor of about 2. To synthesize those findings, we performed structural equation modeling, which showed that plants but not microbial communities were responsible for significantly higher soil respiration rates in burned sites. Together, our results demonstrate that fire 'reboots' the grassland ecosystem by differentially regulating plant and soil microbial communities, leading to significant changes in soil C and N dynamics.

  View details for DOI 10.1111/gcb.14852

  View details for Web of Science ID 000511917700019

  View details for PubMedID 31562826

• Climate-driven risks to the climate mitigation potential of forests. Science (New York, N.Y.) Anderegg, W. R., Trugman, A. T., Badgley, G. n., Anderson, C. M., Bartuska, A. n., Ciais, P. n., Cullenward, D. n., Field, C. B., Freeman, J. n., Goetz, S. J., Hicke, J. A., Huntzinger, D. n., Jackson, R. B., Nickerson, J. n., Pacala, S. n., Randerson, J. T. 2020; 368 (6497)

  Abstract

  Forests have considerable potential to help mitigate human-caused climate change and provide society with many cobenefits. However, climate-driven risks may fundamentally compromise forest carbon sinks in the 21st century. Here, we synthesize the current understanding of climate-driven risks to forest stability from fire, drought, biotic agents, and other disturbances. We review how efforts to use forests as natural climate solutions presently consider and could more fully embrace current scientific knowledge to account for these climate-driven risks. Recent advances in vegetation physiology, disturbance ecology, mechanistic vegetation modeling, large-scale ecological observation networks, and remote sensing are improving current estimates and forecasts of the risks to forest stability. A more holistic understanding and quantification of such risks will help policy-makers and other stakeholders effectively use forests as natural climate solutions.

  View details for DOI 10.1126/science.aaz7005

  View details for PubMedID 32554569

• The future of bioenergy GLOBAL CHANGE BIOLOGY Reid, W. V., Ali, M. K., Field, C. B. 2020; 26 (1): 274–86

  Abstract

  Energy from biomass plays a large and growing role in the global energy system. Energy from biomass can make significant contributions to reducing carbon emissions, especially from difficult-to-decarbonize sectors like aviation, heavy transport, and manufacturing. But land-intensive bioenergy often entails substantial carbon emissions from land-use change as well as production, harvesting, and transportation. In addition, land-intensive bioenergy scales only with the utilization of vast amounts of land, a resource that is fundamentally limited in supply. Because of the land constraint, the intrinsically low yields of energy per unit of land area, and rapid technological progress in competing technologies, land intensive bioenergy makes the most sense as a transitional element of the global energy mix, playing an important role over the next few decades and then fading, probably after mid-century. Managing an effective trajectory for land-intensive bioenergy will require an unusual mix of policies and incentives that encourage appropriate utilization in the short term but minimize lock-in in the longer term.

  View details for DOI 10.1111/gcb.14883

  View details for Web of Science ID 000500557800001

  View details for PubMedID 31642554

  View details for PubMedCentralID PMC6973137

• Managed retreat through voluntary buyouts of flood-prone properties. Science advances Mach, K. J., Kraan, C. M., Hino, M., Siders, A. R., Johnston, E. M., Field, C. B. 2019; 5 (10): eaax8995

  Abstract

  Retreat from some areas will become unavoidable under intensifying climate change. Existing deployments of managed retreat are at small scale compared to potential future needs, leaving open questions about where, when, and how retreat under climate change will occur. Here, we analyze more than 40,000 voluntary buyouts of flood-prone properties in the United States, in which homeowners sell properties to the government and the land is restored to open space. In contrast to model-based evaluation of potential future retreat, local governments in counties with higher population and income are more likely to administer buyouts. The bought-out properties themselves, however, are concentrated in areas of greater social vulnerability within these counties, pointing to the importance of assessing the equity of buyout implementation and outcomes. These patterns demonstrate the challenges associated with locally driven implementation of managed retreat and the potential benefits of experimentation with different approaches to retreat.

  View details for DOI 10.1126/sciadv.aax8995

  View details for PubMedID 31633030

• Methane removal and atmospheric restoration NATURE SUSTAINABILITY Jackson, R. B., Solomon, E. I., Canadell, J. G., Cargnello, M., Field, C. B. 2019; 2 (6): 436–38

  View details for DOI 10.1038/s41893-019-0299-x

  View details for Web of Science ID 000471032700002

• Natural climate solutions are not enough. Science (New York, N.Y.) Anderson, C. M., DeFries, R. S., Litterman, R., Matson, P. A., Nepstad, D. C., Pacala, S., Schlesinger, W. H., Shaw, M. R., Smith, P., Weber, C., Field, C. B. 2019; 363 (6430): 933–34

  View details for PubMedID 30819953

• Strengthened scientific support for the Endangerment Finding for atmospheric greenhouse gases SCIENCE Duffy, P. B., Field, C. B., Diffenbaugh, N. S., Doney, S. C., Dutton, Z., Goodman, S., Heinzerling, L., Hsiang, S., Lobell, D. B., Mickley, L. J., Myers, S., Natali, S. M., Parmesan, C., Tierney, S., Williams, A. 2019; 363 (6427): 597-+

  View details for DOI 10.1126/science.aat5982

  View details for Web of Science ID 000458114200038

• High-tide flooding disrupts local economic activity. Science advances Hino, M., Belanger, S. T., Field, C. B., Davies, A. R., Mach, K. J. 2019; 5 (2): eaau2736

  Abstract

  Evaluation of observed sea level rise impacts to date has emphasized sea level extremes, such as those from tropical cyclones. Far less is known about the consequences of more frequent high-tide flooding. Empirical analysis of the disruption caused by high-tide floods, also called nuisance or sunny-day floods, is challenging due to the short duration of these floods and their impacts. Through a novel approach, we estimate the effects of high-tide flooding on local economic activity. High-tide flooding already measurably affects local economic activity in Annapolis, Maryland, reducing visits to the historic downtown by 1.7% (95% confidence interval, 1.0 to 2.6%). With 3 and 12 inches of additional sea level rise, high-tide floods would reduce visits by 3.6% (3.2 to 4.0%) and 24% (19 to 28%), respectively. A more comprehensive understanding of the impacts of high-tide flooding can help to guide efficient responses from local adaptations to global mitigation of climate change.

  View details for PubMedID 30793026

• Long-term elevated CO2 shifts composition of soil microbial communities in a Californian annual grassland, reducing growth and N utilization potentials. The Science of the total environment Yang, S. n., Zheng, Q. n., Yuan, M. n., Shi, Z. n., Chiariello, N. R., Docherty, K. M., Dong, S. n., Field, C. B., Gu, Y. n., Gutknecht, J. n., Hungate, B. A., Le Roux, X. n., Ma, X. n., Niboyet, A. n., Yuan, T. n., Zhou, J. n., Yang, Y. n. 2019; 652: 1474–81

  Abstract

  The continuously increasing concentration of atmospheric CO2 has considerably altered ecosystem functioning. However, few studies have examined the long-term (i.e. over a decade) effect of elevated CO2 on soil microbial communities. Using 16S rRNA gene amplicons and a GeoChip microarray, we investigated soil microbial communities from a Californian annual grassland after 14 years of experimentally elevated CO2 (275 ppm higher than ambient). Both taxonomic and functional gene compositions of the soil microbial community were modified by elevated CO2. There was decrease in relative abundance for taxa with higher ribosomal RNA operon (rrn) copy number under elevated CO2, which is a functional trait that responds positively to resource availability in culture. In contrast, taxa with lower rrn copy number were increased by elevated CO2. As a consequence, the abundance-weighted average rrn copy number of significantly changed OTUs declined from 2.27 at ambient CO2 to 2.01 at elevated CO2. The nitrogen (N) fixation gene nifH and the ammonium-oxidizing gene amoA significantly decreased under elevated CO2 by 12.6% and 6.1%, respectively. Concomitantly, nitrifying enzyme activity decreased by 48.3% under elevated CO2, albeit this change was not significant. There was also a substantial but insignificant decrease in available soil N, with both nitrate (NO3-) (-27.4%) and ammonium (NH4+) (-15.4%) declining. Further, a large number of microbial genes related to carbon (C) degradation were also affected by elevated CO2, whereas those related to C fixation remained largely unchanged. The overall changes in microbial communities and soil N pools induced by long-term elevated CO2 suggest constrained microbial N decomposition, thereby slowing the potential maximum growth rate of the microbial community.

  View details for PubMedID 30586832

• Climate as a risk factor for armed conflict. Nature Mach, K. J., Kraan, C. M., Adger, W. N., Buhaug, H. n., Burke, M. n., Fearon, J. D., Field, C. B., Hendrix, C. S., Maystadt, J. F., O'Loughlin, J. n., Roessler, P. n., Scheffran, J. n., Schultz, K. A., von Uexkull, N. n. 2019

  Abstract

  Research findings on the relationship between climate and conflict are diverse and contested. Here we assess the current understanding of the relationship between climate and conflict, based on the structured judgments of experts from diverse disciplines. These experts agree that climate has affected organized armed conflict within countries. However, other drivers, such as low socioeconomic development and low capabilities of the state, are judged to be substantially more influential, and the mechanisms of climate-conflict linkages remain a key uncertainty. Intensifying climate change is estimated to increase future risks of conflict.

  View details for DOI 10.1038/s41586-019-1300-6

  View details for PubMedID 31189956

• Terrestrial Gross Primary Production: Using NIRV to Scale from Site to Globe. Global change biology Badgley, G. n., Anderegg, L. D., Berry, J. A., Field, C. B. 2019

  Abstract

  Terrestrial photosynthesis is the largest and one of the most uncertain fluxes in the global carbon cycle. We find that NIRV , a remotely sensed measure of canopy structure, accurately predicts photosynthesis at FLUXNET validation sites at monthly to annual timescales (R2 = 0.68), without the need for difficult to acquire information about environmental factors that constrain photosynthesis at short timescales. Scaling the relationship between GPP and NIRV from FLUXNET eddy covariance sites, we estimate global annual terrestrial photosynthesis to be 147 Pg C y-1 (95% credible interval 131-163 Pg C y-1 ), which falls between bottom-up GPP estimates and the top-down global constraint on GPP from oxygen isotopes. NIRV -derived estimates of GPP are systematically higher than existing bottom-up estimates, especially throughout the mid-latitudes. Progress in improving estimated GPP from NIRV can come from improved cloud-screening in satellite data and increased resolution of vegetation characteristics, especially photosynthetic pathway. This article is protected by copyright. All rights reserved.

  View details for DOI 10.1111/gcb.14729

  View details for PubMedID 31199543

• Strengthened scientific support for the Endangerment Finding for atmospheric greenhouse gases. Science (New York, N.Y.) Duffy, P. B., Field, C. B., Diffenbaugh, N. S., Doney, S. C., Dutton, Z., Goodman, S., Heinzerling, L., Hsiang, S., Lobell, D. B., Mickley, L. J., Myers, S., Natali, S. M., Parmesan, C., Tierney, S., Williams, A. P. 2018

  Abstract

  We assess scientific evidence that has emerged since the U.S. Environmental Protection Agency's 2009 Endangerment Finding for six well-mixed greenhouse gases, and find that this new evidence lends increased support to the conclusion that these gases pose a danger to public health and welfare. Newly available evidence about a wide range of observed and projected impacts strengthens the association between risk of some of these impacts and anthropogenic climate change; indicates that some impacts or combinations of impacts have the potential to be more severe than previously understood; and identifies substantial risk of additional impacts through processes and pathways not considered in the endangerment finding.

  View details for PubMedID 30545843

• Forest management in the Sierra Nevada provides limited carbon storage potential: an expert elicitation ECOSPHERE Lalonde, S. J., Mach, K. J., Anderson, C. M., Francis, E. J., Sanchez, D. L., Stanton, C. Y., Turner, P. A., Field, C. B. 2018; 9 (7)

  View details for DOI 10.1002/ecs2.2321

  View details for Web of Science ID 000441526900019

• Net-zero emissions energy systems SCIENCE Davis, S. J., Lewis, N. S., Shaner, M., Aggarwal, S., Arent, D., Azevedo, I. L., Benson, S. M., Bradley, T., Brouwer, J., Chiang, Y., Clack, C. M., Cohen, A., Doig, S., Edmonds, J., Fennell, P., Field, C. B., Hannegan, B., Hodge, B., Hoffert, M. I., Ingersoll, E., Jaramillo, P., Lackner, K. S., Mach, K. J., Mastrandrea, M., Ogden, J., Peterson, P. F., Sanchez, D. L., Sperling, D., Stagner, J., Trancik, J. E., Yang, C., Caldeira, K. 2018; 360 (6396): 1419-+

  Abstract

  Some energy services and industrial processes-such as long-distance freight transport, air travel, highly reliable electricity, and steel and cement manufacturing-are particularly difficult to provide without adding carbon dioxide (CO2) to the atmosphere. Rapidly growing demand for these services, combined with long lead times for technology development and long lifetimes of energy infrastructure, make decarbonization of these services both essential and urgent. We examine barriers and opportunities associated with these difficult-to-decarbonize services and processes, including possible technological solutions and research and development priorities. A range of existing technologies could meet future demands for these services and processes without net addition of CO2 to the atmosphere, but their use may depend on a combination of cost reductions via research and innovation, as well as coordinated deployment and integration of operations across currently discrete energy industries.

  View details for PubMedID 29954954

• Unprecedented rates of land-use transformation in modelled climate change mitigation pathways NATURE SUSTAINABILITY Turner, P. A., Field, C. B., Lobell, D. B., Sanchez, D. L., Mach, K. J. 2018; 1 (5): 240–45

  View details for DOI 10.1038/s41893-018-0063-7

  View details for Web of Science ID 000439189400012

• The global overlap of bioenergy and carbon sequestration potential CLIMATIC CHANGE Turner, P. A., Mach, K. J., Lobell, D. B., Benson, S. M., Baik, E., Sanchez, D. L., Field, C. B. 2018; 148 (1-2): 1–10

  View details for DOI 10.1007/s10584-018-2189-z

  View details for Web of Science ID 000431788500001

• Managing cropland and rangeland for climate mitigation: an expert elicitation on soil carbon in California CLIMATIC CHANGE Stanton, C. Y., Mach, K. J., Turner, P. A., Lalonde, S. J., Sanchez, D. L., Field, C. B. 2018; 147 (3-4): 633–46

  View details for DOI 10.1007/s10584-018-2142-1

  View details for Web of Science ID 000428427200018

• Decoupled dimensions of leaf economic and anti-herbivore defense strategies in a tropical canopy tree community OECOLOGIA Chauvin, K., Asner, G. P., Martin, R. E., Kress, W. J., Wright, S. J., Field, C. B. 2018; 186 (3): 765–82

  Abstract

  Trade-offs among plant functional traits indicate diversity in plant strategies of growth and survival. The leaf economics spectrum (LES) reflects a trade-off between short-term carbon gain and long-term leaf persistence. A related trade-off, between foliar growth and anti-herbivore defense, occurs among plants growing in contrasting resource regimes, but it is unclear whether this trade-off is maintained within plant communities, where resource gradients are minimized. The LES and the growth-defense trade-off involve related traits, but the extent to which these trade-off dimensions are correlated is poorly understood. We assessed the relationship between leaf economic and anti-herbivore defense traits among sunlit foliage of 345 canopy trees in 83 species on Barro Colorado Island, Panama. We quantified ten traits related to resource allocation and defense, and identified patterns of trait co-variation using multivariate ordination. We tested whether traits and ordination axes were correlated with patterns of phylogenetic relatedness, juvenile demographic trade-offs, or topo-edaphic variation. Two independent axes described ~ 60% of the variation among canopy trees. Axis 1 revealed a trade-off between leaf nutritional and structural investment, consistent with the LES. Physical defense traits were largely oriented along this axis. Axis 2 revealed a trade-off between investments in phenolic defenses versus other foliar defenses, which we term the leaf defense spectrum. Phylogenetic relationships and topo-edaphic variation largely did not explain trait co-variation. Our results suggest that some trade-offs among the growth and defense traits of outer-canopy trees may be captured by the LES, while others may occur along additional resource allocation dimensions.

  View details for PubMedID 29302802

• Assessing Cumulative Effects of Climate Change Manipulations on Phosphorus Limitation in a Californian Grassland ENVIRONMENTAL SCIENCE & TECHNOLOGY Mellett, T., Selvin, C., Defforey, D., Roberts, K., Lecher, A. L., Dennis, K., Gutknecht, J., Field, C., Paytan, A. 2018; 52 (1): 98–106

  Abstract

  Grasslands throughout the world are responding in diverse ways to changing climate and environmental conditions. In this study we analyze indicators of phosphorus limitation including phosphorus concentrations, phosphorus to nitrogen, and carbon ratios, oxygen isotope ratios of phosphate in vegetation, and phosphatase enzyme activity in soil to shed light on potential effects of climate change on phosphorus availability to grassland vegetation. The study was conducted at the Jasper Ridge Global Change Experiment (JRGCE), California where manipulations mimicking increases in temperature, water, nitrogen and carbon-dioxide have been maintained for over 15 years. We compare our results to an earlier study conducted 3 years after the start of the experiment, in order to assess any change in the response of phosphorus over time. Our results suggest that a decade later the measured indicators show similar or only slightly stronger responses. Specifically, addition of nitrogen, the principle parameter controlling biomass growth, increased phosphorus demand but thresholds that suggest P limitation were not reached. A study documenting changes in net primary productivity (NPP) over time at the JRGCE also could not identify a progressive effect of the manipulations on NPP. Combined these results indicate that the vegetation in these grassland systems is not very sensitive to the range of climate parameters tested.

  View details for DOI 10.1021/acs.est.7b04362

  View details for Web of Science ID 000419419500012

  View details for PubMedID 29192763

• Geospatial analysis of near-term potential for carbon-negative bioenergy in the United States. Proceedings of the National Academy of Sciences of the United States of America Baik, E. n., Sanchez, D. L., Turner, P. A., Mach, K. J., Field, C. B., Benson, S. M. 2018; 115 (13): 3290–95

  Abstract

  Bioenergy with carbon capture and storage (BECCS) is a negative-emissions technology that may play a crucial role in climate change mitigation. BECCS relies on the capture and sequestration of carbon dioxide (CO2) following bioenergy production to remove and reliably sequester atmospheric CO2Previous BECCS deployment assessments have largely overlooked the potential lack of spatial colocation of suitable storage basins and biomass availability, in the absence of long-distance biomass and CO2transport. These conditions could constrain the near-term technical deployment potential of BECCS due to social and economic barriers that exist for biomass and CO2transport. This study leverages biomass production data and site-specific injection and storage capacity estimates at high spatial resolution to assess the near-term deployment opportunities for BECCS in the United States. If the total biomass resource available in the United States was mobilized for BECCS, an estimated 370 Mt CO2⋅y-1of negative emissions could be supplied in 2020. However, the absence of long-distance biomass and CO2transport, as well as limitations imposed by unsuitable regional storage and injection capacities, collectively decrease the technical potential of negative emissions to 100 Mt CO2⋅y-1Meeting this technical potential may require large-scale deployment of BECCS technology in more than 1,000 counties, as well as widespread deployment of dedicated energy crops. Specifically, the Illinois basin, Gulf region, and western North Dakota have the greatest potential for near-term BECCS deployment. High-resolution spatial assessment as conducted in this study can inform near-term opportunities that minimize social and economic barriers to BECCS deployment.

  View details for PubMedID 29531081

  View details for PubMedCentralID PMC5879697

• Forest offsets partner climate-change mitigation with conservation FRONTIERS IN ECOLOGY AND THE ENVIRONMENT Anderson, C. M., Field, C. B., Mach, K. J. 2017; 15 (7): 359–65

  View details for DOI 10.1002/fee.1515

  View details for Web of Science ID 000408822300013

• Rightsizing carbon dioxide removal. Science (New York, N.Y.) Field, C. B., Mach, K. J. 2017; 356 (6339): 706-707

  View details for DOI 10.1126/science.aam9726

  View details for PubMedID 28522498

• Experimental fire increases soil carbon dioxide efflux in a grassland long-term multifactor global change experiment GLOBAL CHANGE BIOLOGY Strong, A. L., Johnson, T. P., Chiariello, N. R., Field, C. B. 2017; 23 (5): 1975-1987

  View details for DOI 10.1111/gcb.13525

  View details for Web of Science ID 000397800600018

• Experimental fire increases soil carbon dioxide efflux in a grassland long-term multifactor global change experiment. Global change biology Strong, A. L., Johnson, T. P., Chiariello, N. R., Field, C. B. 2017; 23 (5): 1975-1987

  Abstract

  Numerous studies have demonstrated that soil respiration rates increase under experimental warming, although the long-term, multiyear dynamics of this feedback are not well constrained. Less is known about the effects of single, punctuated events in combination with other longer-duration anthropogenic influences on the dynamics of soil carbon (C) loss. In 2012 and 2013, we assessed the effects of decadal-scale anthropogenic global change - warming, increased nitrogen (N) deposition, elevated carbon dioxide (CO2 ), and increased precipitation - on soil respiration rates in an annual-dominated Mediterranean grassland. We also investigated how controlled fire and an artificial wet-up event, in combination with exposure to the longer-duration anthropogenic global change factors, influenced the dynamics of C cycling in this system. Decade-duration surface soil warming (1-2 °C) had no effect on soil respiration rates, while +N addition and elevated CO2 concentrations increased growing-season soil CO2 efflux rates by increasing annual aboveground net primary production (NPP) and belowground fine root production, respectively. Low-intensity experimental fire significantly elevated soil CO2 efflux rates in the next growing season. Based on mixed-effects modeling and structural equation modeling, low-intensity fire increased growing-season soil respiration rates through a combination of three mechanisms: large increases in soil temperature (3-5 °C), significant increases in fine root production, and elevated aboveground NPP. Our study shows that in ecosystems where soil respiration has acclimated to moderate warming, further increases in soil temperature can stimulate greater soil CO2 efflux. We also demonstrate that punctuated short-duration events such as fire can influence soil C dynamics with implications for both the parameterization of earth system models (ESMs) and the implementation of climate change mitigation policies that involve land-sector C accounting.

  View details for DOI 10.1111/gcb.13525

  View details for PubMedID 27859942

• Managed retreat as a response to natural hazard risk NATURE CLIMATE CHANGE Hino, M., Field, C. B., Mach, K. J. 2017; 7 (5): 364-?

  View details for DOI 10.1038/NCLIMATE3252

  View details for Web of Science ID 000400373500018

• Canopy near-infrared reflectance and terrestrial photosynthesis. Science advances Badgley, G., Field, C. B., Berry, J. A. 2017; 3 (3)

  Abstract

  Global estimates of terrestrial gross primary production (GPP) remain highly uncertain, despite decades of satellite measurements and intensive in situ monitoring. We report a new approach for quantifying the near-infrared reflectance of terrestrial vegetation (NIRV). NIRV provides a foundation for a new approach to estimate GPP that consistently untangles the confounding effects of background brightness, leaf area, and the distribution of photosynthetic capacity with depth in canopies using existing moderate spatial and spectral resolution satellite sensors. NIRV is strongly correlated with solar-induced chlorophyll fluorescence, a direct index of photons intercepted by chlorophyll, and with site-level and globally gridded estimates of GPP. NIRV makes it possible to use existing and future reflectance data as a starting point for accurately estimating GPP.

  View details for DOI 10.1126/sciadv.1602244

  View details for PubMedID 28345046

• Toward the Next Generation of Assessment ANNUAL REVIEW OF ENVIRONMENT AND RESOURCES, VOL 42 Mach, K. J., Field, C. B., Gadgil, A., Tomich, T. P. 2017; 42: 569–97

  View details for DOI 10.1146/annurev-environ-102016-061007

  View details for Web of Science ID 000413586400021

• Nonlinear, interacting responses to climate limit grassland production under global change PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Zhu, K., Chiariello, N. R., Tobeck, T., Fukami, T., Field, C. B. 2016; 113 (38): 10589-10594

  Abstract

  Global changes in climate, atmospheric composition, and pollutants are altering ecosystems and the goods and services they provide. Among approaches for predicting ecosystem responses, long-term observations and manipulative experiments can be powerful approaches for resolving single-factor and interactive effects of global changes on key metrics such as net primary production (NPP). Here we combine both approaches, developing multidimensional response surfaces for NPP based on the longest-running, best-replicated, most-multifactor global-change experiment at the ecosystem scale-a 17-y study of California grassland exposed to full-factorial warming, added precipitation, elevated CO2, and nitrogen deposition. Single-factor and interactive effects were not time-dependent, enabling us to analyze each year as a separate realization of the experiment and extract NPP as a continuous function of global-change factors. We found a ridge-shaped response surface in which NPP is humped (unimodal) in response to temperature and precipitation when CO2 and nitrogen are ambient, with peak NPP rising under elevated CO2 or nitrogen but also shifting to lower temperatures. Our results suggest that future climate change will push this ecosystem away from conditions that maximize NPP, but with large year-to-year variability.

  View details for DOI 10.1073/pnas.1606734113

  View details for PubMedID 27601643

• Mapping the climate change challenge NATURE CLIMATE CHANGE Hallegatte, S., Rogelj, J., Allen, M., Clarke, L., Edenhofer, O., Field, C. B., Friedlingstein, P., van Kesteren, L., Knutti, R., Mach, K. J., Mastrandrea, M., Michel, A., Minx, J., Oppenheimer, M., Plattner, G., Riahi, K., Schaeffer, M., Stocker, T. F., Van Vuuren, D. P. 2016; 6 (7): 663-668

  View details for DOI 10.1038/NCLIMATE3057

  View details for Web of Science ID 000378608900014

• Predicting the Responses of Soil Nitrite-Oxidizers to Multi-Factorial Global Change: A Trait-Based Approach FRONTIERS IN MICROBIOLOGY Le Roux, X., Bouskill, N. J., Niboyet, A., Barthes, L., Dijkstra, P., Field, C. B., Hungate, B. A., Lerondelle, C., Pommier, T., Tang, J., Terada, A., Tourna, M., Poly, F. 2016; 7

  Abstract

  Soil microbial diversity is huge and a few grams of soil contain more bacterial taxa than there are bird species on Earth. This high diversity often makes predicting the responses of soil bacteria to environmental change intractable and restricts our capacity to predict the responses of soil functions to global change. Here, using a long-term field experiment in a California grassland, we studied the main and interactive effects of three global change factors (increased atmospheric CO2 concentration, precipitation and nitrogen addition, and all their factorial combinations, based on global change scenarios for central California) on the potential activity, abundance and dominant taxa of soil nitrite-oxidizing bacteria (NOB). Using a trait-based model, we then tested whether categorizing NOB into a few functional groups unified by physiological traits enables understanding and predicting how soil NOB respond to global environmental change. Contrasted responses to global change treatments were observed between three main NOB functional types. In particular, putatively mixotrophic Nitrobacter, rare under most treatments, became dominant under the 'High CO2+Nitrogen+Precipitation' treatment. The mechanistic trait-based model, which simulated ecological niches of NOB types consistent with previous ecophysiological reports, helped predicting the observed effects of global change on NOB and elucidating the underlying biotic and abiotic controls. Our results are a starting point for representing the overwhelming diversity of soil bacteria by a few functional types that can be incorporated into models of terrestrial ecosystems and biogeochemical processes.

  View details for DOI 10.3389/fmicb.2016.00628

  View details for Web of Science ID 000376000100001

  View details for PubMedID 27242680

  View details for PubMedCentralID PMC4868854

• Colocation opportunities for large solar infrastructures and agriculture in drylands APPLIED ENERGY Ravi, S., Macknick, J., Lobell, D., Field, C., Ganesan, K., Jain, R., Elchinger, M., Stoltenberg, B. 2016; 165: 383-392

  View details for DOI 10.1016/j.apenergy.2015.12.078

  View details for Web of Science ID 000372676400031

• Phylogenetic Structure of Foliar Spectral Traits in Tropical Forest Canopies REMOTE SENSING McManus, K. M., Asner, G. P., Martin, R. E., Dexter, K. G., Kress, W. J., Field, C. B. 2016; 8 (3)

  View details for DOI 10.3390/rs8030196

  View details for Web of Science ID 000373627400102

• Building a sustained climate assessment process CLIMATIC CHANGE Buizer, J. L., Dow, K., Black, M. E., Jacobs, K. L., Waple, A., Moss, R. H., Moser, S., Luers, A., Gustafson, D. I., RICHMOND, T. C., Hays, S. L., Field, C. B. 2016; 135 (1): 23-37

  View details for DOI 10.1007/s10584-015-1501-4

  View details for Web of Science ID 000375465700003

• In-field yellow starthistle (Centaurea solstitialis) volatile composition under elevated temperature and CO2 and implications for future control CHEMOECOLOGY Oster, M., Beck, J. J., Furrow, R. E., Yeung, K., Field, C. B. 2015; 25 (6): 313-323

  View details for DOI 10.1007/s00049-015-0200-y

  View details for Web of Science ID 000362882500004

• Projections of future meteorological drought and wet periods in the Amazon PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Duffy, P. B., Brando, P., Asner, G. P., Field, C. B. 2015; 112 (43): 13172-13177

  View details for DOI 10.1073/pnas.1421010112

  View details for Web of Science ID 000363458100035

  View details for PubMedID 26460046

• Tree mortality predicted from drought-induced vascular damage NATURE GEOSCIENCE Anderegg, W. R., Flint, A., Huang, C., Flint, L., Berry, J. A., Davis, F. W., Sperry, J. S., Field, C. B. 2015; 8 (5): 367-371

  View details for DOI 10.1038/NGEO2400

  View details for Web of Science ID 000353640100013

• Linking vegetation patterns to environmental gradients and human impacts in a mediterranean-type island ecosystem LANDSCAPE ECOLOGY Dahlin, K. M., Asner, G. P., Field, C. B. 2014; 29 (9): 1571-1585

  View details for DOI 10.1007/s10980-014-0076-1

  View details for Web of Science ID 000343648700009

• Orientation behavior of predaceous ground beetle species in response to volatile emissions identified from yellow starthistle damaged by an invasive slug ARTHROPOD-PLANT INTERACTIONS Oster, M., Smith, L., Beck, J. J., Howard, A., Field, C. B. 2014; 8 (5): 429-437

  View details for DOI 10.1007/s11829-014-9322-3

  View details for Web of Science ID 000344733300007

• Loss of whole-tree hydraulic conductance during severe drought and multi-year forest die-off OECOLOGIA Anderegg, W. R., Anderegg, L. D., Berry, J. A., Field, C. B. 2014; 175 (1): 11-23

  Abstract

  Understanding the pathways through which drought stress kills woody vegetation can improve projections of the impacts of climate change on ecosystems and carbon-cycle feedbacks. Continuous in situ measurements of whole trees during drought and as trees die hold promise to illuminate physiological pathways but are relatively rare. We monitored leaf characteristics, water use efficiency, water potentials, branch hydraulic conductivity, soil moisture, meteorological variables, and sap flux on mature healthy and sudden aspen decline-affected (SAD) trembling aspen (Populus tremuloides) ramets over two growing seasons, including a severe summer drought. We calculated daily estimates of whole-ramet hydraulic conductance and modeled whole-ramet assimilation. Healthy ramets experienced rapid declines of whole-ramet conductance during the severe drought, providing an analog for what likely occurred during the previous drought that induced SAD. Even in wetter periods, SAD-affected ramets exhibited fivefold lower whole-ramet hydraulic conductance and sevenfold lower assimilation than counterpart healthy ramets, mediated by changes in leaf area, water use efficiency, and embolism. Extant differences between healthy and SAD ramets reveal that ongoing multi-year forest die-off is primarily driven by loss of whole-ramet hydraulic capability, which in turn limits assimilation capacity. Branch-level measurements largely captured whole-plant hydraulic limitations during drought and mortality, but whole-plant measurements revealed a potential role of other losses in the hydraulic continuum. Our results highlight the importance of a whole-tree perspective in assessing physiological pathways to tree mortality and indicate that the effects of mortality on these forests' assimilation and productivity are larger than expected based on canopy leaf area differences.

  View details for DOI 10.1007/s00442-013-2875-5

  View details for Web of Science ID 000334691600002

  View details for PubMedID 24394863

• Linking rainforest ecophysiology and microclimate through fusion of airborne LiDAR and hyperspectral imagery ECOSPHERE Broadbent, E. N., Zambrano, A. M., Asner, G. P., Field, C. B., Rosenheim, B. E., Kennedy-Bowdoin, T., Knapp, D. E., Burke, D., Giardina, C., Cordell, S. 2014; 5 (5)

  View details for DOI 10.1890/ES13-00255.1

  View details for Web of Science ID 000337164100008

• Tradeoffs and Synergies between Biofuel Production and Large Solar Infrastructure in Deserts. Environmental science & technology Ravi, S., Lobell, D. B., Field, C. B. 2014; 48 (5): 3021-3030

  Abstract

  Solar energy installations in deserts are on the rise, fueled by technological advances and policy changes. Deserts, with a combination of high solar radiation and availability of large areas unusable for crop production are ideal locations for large solar installations. However, for efficient power generation, solar infrastructures use large amounts of water for construction and operation. We investigated the water use and greenhouse gas (GHG) emissions associated with solar installations in North American deserts in comparison to agave-based biofuel production, another widely promoted potential energy source from arid systems. We determined the uncertainty in our analysis by a Monte Carlo approach that varied the most important parameters, as determined by sensitivity analysis. We considered the uncertainty in our estimates as a result of variations in the number of solar modules ha(-1), module efficiency, number of agave plants ha(-1), and overall sugar conversion efficiency for agave. Further, we considered the uncertainty in revenue and returns as a result of variations in the wholesale price of electricity and installation cost of solar photovoltaic (PV), wholesale price of agave ethanol, and cost of agave cultivation and ethanol processing. The life-cycle analyses show that energy outputs and GHG offsets from solar PV systems, mean energy output of 2405 GJ ha(-1) year(-1) (5 and 95% quantile values of 1940-2920) and mean GHG offsets of 464 Mg of CO2 equiv ha(-1) year(-1) (375-562), are much larger than agave, mean energy output from 206 (171-243) to 61 (50-71) GJ ha(-1) year(-1) and mean GHG offsets from 18 (14-22) to 4.6 (3.7-5.5) Mg of CO2 equiv ha(-1) year(-1), depending upon the yield scenario of agave. Importantly though, water inputs for cleaning solar panels and dust suppression are similar to amounts required for annual agave growth, suggesting the possibility of integrating the two systems to maximize the efficiency of land and water use to produce both electricity and liquid fuel. A life-cycle analysis of a hypothetical colocation indicated higher returns per m(3) of water used than either system alone. Water requirements for energy production were 0.22 L MJ(-1) (0.28-0.19) and 0.42 L MJ(-1) (0.52-0.35) for solar PV-agave (baseline yield) and solar PV-agave (high yield), respectively. Even though colocation may not be practical in all locations, in some water-limited areas, colocated solar PV-agave systems may provide attractive economic incentives in addition to efficient land and water use.

  View details for DOI 10.1021/es404950n

  View details for PubMedID 24467248

• Modeling the impact of carbon farming on land use in a New Zealand landscape ENVIRONMENTAL SCIENCE & POLICY Funk, J. M., Field, C. B., Kerr, S., Daigneault, A. 2014; 37: 1-10

  View details for DOI 10.1016/j.envsci.2013.08.008

  View details for Web of Science ID 000333723800001

• Land-Use Efficiency of Big Solar ENVIRONMENTAL SCIENCE & TECHNOLOGY Hernandez, R. R., Hoffacker, M. K., Field, C. B. 2014; 48 (2): 1315-1323

  Abstract

  As utility-scale solar energy (USSE) systems increase in size and numbers globally, there is a growing interest in understanding environmental interactions between solar energy development and land-use decisions. Maximizing the efficient use of land for USSE is one of the major challenges in realizing the full potential of solar energy; however, the land-use efficiency (LUE; Wm(-2)) of USSE remains ambiguous. We quantified the capacity-based LUE of 183 USSE installations (>20 MW; planned, under construction, and operating) using California as a case study. In California, USSE installations are concentrated in the Central Valley and interior regions of southern California and have a LUE of 35.0 Wm(-2). The installations occupy approximately 86,000 ha and more land is allocated for photovoltaic schemes (72 294 ha) than for concentrating solar power (13,604 ha). Photovoltaic installations are greater in abundance (93%) than concentrating solar power, but technology type and nameplate capacity has no impact on capacity-based LUE. More USSE installations are on private land (80%) and have a significantly greater LUE (35.8 Wm(-2)) than installations on public land (25.4 Wm(-2)). Our findings can be used to better understand and improve the LUE of USSE, thereby maximizing economic, energetic, and environmental returns on investments.

  View details for DOI 10.1021/es4043726

  View details for Web of Science ID 000330205000058

  View details for PubMedID 24351039

• Integrating stand and soil properties to understand foliar nutrient dynamics during forest succession following slash-and-burn agriculture in the Bolivian Amazon. PloS one Broadbent, E. N., Almeyda Zambrano, A. M., Asner, G. P., Soriano, M., Field, C. B., de Souza, H. R., Peña-Claros, M., Adams, R. I., Dirzo, R., Giles, L. 2014; 9 (2)

  Abstract

  Secondary forests cover large areas of the tropics and play an important role in the global carbon cycle. During secondary forest succession, simultaneous changes occur among stand structural attributes, soil properties, and species composition. Most studies classify tree species into categories based on their regeneration requirements. We use a high-resolution secondary forest chronosequence to assign trees to a continuous gradient in species successional status assigned according to their distribution across the chronosequence. Species successional status, not stand age or differences in stand structure or soil properties, was found to be the best predictor of leaf trait variation. Foliar δ(13)C had a significant positive relationship with species successional status, indicating changes in foliar physiology related to growth and competitive strategy, but was not correlated with stand age, whereas soil δ(13)C dynamics were largely constrained by plant species composition. Foliar δ(15)N had a significant negative correlation with both stand age and species successional status, - most likely resulting from a large initial biomass-burning enrichment in soil (15)N and (13)C and not closure of the nitrogen cycle. Foliar %C was neither correlated with stand age nor species successional status but was found to display significant phylogenetic signal. Results from this study are relevant to understanding the dynamics of tree species growth and competition during forest succession and highlight possibilities of, and potentially confounding signals affecting, the utility of leaf traits to understand community and species dynamics during secondary forest succession.

  View details for DOI 10.1371/journal.pone.0086042

  View details for PubMedID 24516525

  View details for PubMedCentralID PMC3917844

• Integrating Stand and Soil Properties to Understand Foliar Nutrient Dynamics during Forest Succession Following Slash-and-Burn Agriculture in the Bolivian Amazon. PloS one Broadbent, E. N., Almeyda Zambrano, A. M., Asner, G. P., Soriano, M., Field, C. B., de Souza, H. R., Peña-Claros, M., Adams, R. I., Dirzo, R., Giles, L. 2014; 9 (2): e86042

  Abstract

  Secondary forests cover large areas of the tropics and play an important role in the global carbon cycle. During secondary forest succession, simultaneous changes occur among stand structural attributes, soil properties, and species composition. Most studies classify tree species into categories based on their regeneration requirements. We use a high-resolution secondary forest chronosequence to assign trees to a continuous gradient in species successional status assigned according to their distribution across the chronosequence. Species successional status, not stand age or differences in stand structure or soil properties, was found to be the best predictor of leaf trait variation. Foliar δ(13)C had a significant positive relationship with species successional status, indicating changes in foliar physiology related to growth and competitive strategy, but was not correlated with stand age, whereas soil δ(13)C dynamics were largely constrained by plant species composition. Foliar δ(15)N had a significant negative correlation with both stand age and species successional status, - most likely resulting from a large initial biomass-burning enrichment in soil (15)N and (13)C and not closure of the nitrogen cycle. Foliar %C was neither correlated with stand age nor species successional status but was found to display significant phylogenetic signal. Results from this study are relevant to understanding the dynamics of tree species growth and competition during forest succession and highlight possibilities of, and potentially confounding signals affecting, the utility of leaf traits to understand community and species dynamics during secondary forest succession.

  View details for DOI 10.1371/journal.pone.0086042

  View details for PubMedID 24516525

  View details for PubMedCentralID PMC3917844

• Changes in Ecologically Critical Terrestrial Climate Conditions SCIENCE Diffenbaugh, N. S., Field, C. B. 2013; 341 (6145): 486-492

  Abstract

  Terrestrial ecosystems have encountered substantial warming over the past century, with temperatures increasing about twice as rapidly over land as over the oceans. Here, we review the likelihood of continued changes in terrestrial climate, including analyses of the Coupled Model Intercomparison Project global climate model ensemble. Inertia toward continued emissions creates potential 21st-century global warming that is comparable in magnitude to that of the largest global changes in the past 65 million years but is orders of magnitude more rapid. The rate of warming implies a velocity of climate change and required range shifts of up to several kilometers per year, raising the prospect of daunting challenges for ecosystems, especially in the context of extensive land use and degradation, changes in frequency and severity of extreme events, and interactions with other stresses.

  View details for DOI 10.1126/science.1237123

  View details for Web of Science ID 000322586700039

  View details for PubMedID 23908225

• Seasonal energy storage using bioenergy production from abandoned croplands ENVIRONMENTAL RESEARCH LETTERS Campbell, J. E., Lobell, D. B., Genova, R. C., Zumkehr, A., Field, C. B. 2013; 8 (3)

  View details for DOI 10.1088/1748-9326/8/3/035012

  View details for Web of Science ID 000325247100057

• Risk management and climate change NATURE CLIMATE CHANGE Kunreuther, H., Heal, G., Allen, M., Edenhofer, O., Field, C. B., Yohe, G. 2013; 3 (5): 447-450

  View details for DOI 10.1038/NCLIMATE1740

  View details for Web of Science ID 000319402000008

• Environmental and community controls on plant canopy chemistry in a Mediterranean-type ecosystem. Proceedings of the National Academy of Sciences of the United States of America Dahlin, K. M., Asner, G. P., Field, C. B. 2013; 110 (17): 6895-6900

  Abstract

  Understanding how and why plant communities vary across space has long been a goal of ecology, yet parsing the relative importance of different influences has remained a challenge. Species-specific models are not generalizable, whereas broad plant functional type models lack important detail. Here we consider plant trait patterns at the local scale and ask whether plant chemical traits are more closely linked to environmental gradients or to changes in species composition. We used the visible-to-shortwave infrared (VSWIR) spectrometer of the Carnegie Airborne Observatory to develop maps of four plant chemical traits-leaf nitrogen per mass, leaf carbon per mass, leaf water concentration, and canopy water content-across a diverse Mediterranean-type ecosystem (Jasper Ridge Biological Preserve, CA). For all four traits, plant community alone was the strongest predictor of trait variation (explaining 46-61% of the heterogeneity), whereas environmental gradients accounted for just one fourth of the variation in the traits. This result emphasizes the critical role that species composition plays in mediating nutrient and carbon cycling within and among different communities. Environmental filtering and limits to similarity can act strongly, simultaneously, in a spatially heterogeneous environment, but the local-scale environmental gradients alone cannot account for the variation across this landscape.

  View details for DOI 10.1073/pnas.1215513110

  View details for PubMedID 23569241

  View details for PubMedCentralID PMC3637728

• Drought's legacy: multiyear hydraulic deterioration underlies widespread aspen forest die-off and portends increased future risk GLOBAL CHANGE BIOLOGY Anderegg, W. R., Plavcova, L., Anderegg, L. D., Hacke, U. G., Berry, J. A., Field, C. B. 2013; 19 (4): 1188-1196

  Abstract

  Forest mortality constitutes a major uncertainty in projections of climate impacts on terrestrial ecosystems and carbon-cycle feedbacks. Recent drought-induced, widespread forest die-offs highlight that climate change could accelerate forest mortality with its diverse and potentially severe consequences for the global carbon cycle, ecosystem services, and biodiversity. How trees die during drought over multiple years remains largely unknown and precludes mechanistic modeling and prediction of forest die-off with climate change. Here, we examine the physiological basis of a recent multiyear widespread die-off of trembling aspen (Populus tremuloides) across much of western North America. Using observations from both native trees while they are dying and a rainfall exclusion experiment on mature trees, we measure hydraulic performance over multiple seasons and years and assess pathways of accumulated hydraulic damage. We test whether accumulated hydraulic damage can predict the probability of tree survival over 2 years. We find that hydraulic damage persisted and increased in dying trees over multiple years and exhibited few signs of repair. This accumulated hydraulic deterioration is largely mediated by increased vulnerability to cavitation, a process known as cavitation fatigue. Furthermore, this hydraulic damage predicts the probability of interyear stem mortality. Contrary to the expectation that surviving trees have weathered severe drought, the hydraulic deterioration demonstrated here reveals that surviving regions of these forests are actually more vulnerable to future droughts due to accumulated xylem damage. As the most widespread tree species in North America, increasing vulnerability to drought in these forests has important ramifications for ecosystem stability, biodiversity, and ecosystem carbon balance. Our results provide a foundation for incorporating accumulated drought impacts into climate-vegetation models. Finally, our findings highlight the critical role of drought stress accumulation and repair of stress-induced damage for avoiding plant mortality, presenting a dynamic and contingent framework for drought impacts on forest ecosystems.

  View details for DOI 10.1111/gcb.12100

  View details for Web of Science ID 000315900800020

  View details for PubMedID 23504895

• Simulated hydroclimatic impacts of projected Brazilian sugarcane expansion GEOPHYSICAL RESEARCH LETTERS Georgescu, M., Lobell, D. B., Field, C. B., Mahalov, A. 2013; 40 (5): 972-977

  View details for DOI 10.1002/grl.50206

  View details for Web of Science ID 000318242900032

• Fostering advances in interdisciplinary climate science PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Shaman, J., Solomon, S., Colwell, R. R., Field, C. B. 2013; 110: 3653-3656

  View details for DOI 10.1073/pnas.1301104110

  View details for Web of Science ID 000315842100001

  View details for PubMedID 23440191

• A dual isotope approach to isolate soil carbon pools of different turnover times BIOGEOSCIENCES Torn, M. S., Kleber, M., Zavaleta, E. S., Zhu, B., Field, C. B., Trumbore, S. E. 2013; 10 (12): 8067-8081

  View details for DOI 10.5194/bg-10-8067-2013

  View details for Web of Science ID 000329054600017

• Biophysical Properties of Cultivated Pastures in the Brazilian Savanna Biome: An Analysis in the Spatial-Temporal Domains Based on Ground and Satellite Data REMOTE SENSING Ferreira, L. G., Fernandez, L. E., Sano, E. E., Field, C., Sousa, S. B., Arantes, A. E., Araujo, F. M. 2013; 5 (1): 307-326

  View details for DOI 10.3390/rs5010307

  View details for Web of Science ID 000315402400016

• Linking definitions, mechanisms, and modeling of drought-induced tree death TRENDS IN PLANT SCIENCE Anderegg, W. R., Berry, J. A., Field, C. B. 2012; 17 (12): 693-700

  Abstract

  Tree death from drought and heat stress is a critical and uncertain component in forest ecosystem responses to a changing climate. Recent research has illuminated how tree mortality is a complex cascade of changes involving interconnected plant systems over multiple timescales. Explicit consideration of the definitions, dynamics, and temporal and biological scales of tree mortality research can guide experimental and modeling approaches. In this review, we draw on the medical literature concerning human death to propose a water resource-based approach to tree mortality that considers the tree as a complex organism with a distinct growth strategy. This approach provides insight into mortality mechanisms at the tree and landscape scales and presents promising avenues into modeling tree death from drought and temperature stress.

  View details for Web of Science ID 000312825400003

  View details for PubMedID 23099222

• Carnegie Airborne Observatory-2: Increasing science data dimensionality via high-fidelity multi-sensor fusion REMOTE SENSING OF ENVIRONMENT Asner, G. P., Knapp, D. E., Boardman, J., Green, R. O., Kennedy-Bowdoin, T., Eastwood, M., Martin, R. E., Anderson, C., Field, C. B. 2012; 124: 454-465

  View details for DOI 10.1016/j.rse.2012.06.012

  View details for Web of Science ID 000311247700039

• Theoretical Impact of Changing Albedo on Precipitation at the Southernmost Boundary of the ITCZ in South America EARTH INTERACTIONS Doughty, C. E., Loarie, S. R., Field, C. B. 2012; 16

  View details for DOI 10.1175/2012EI422.1

  View details for Web of Science ID 000307822000001

• Planetary Opportunities: A Social Contract for Global Change Science to Contribute to a Sustainable Future BIOSCIENCE DeFries, R. S., Ellis, E. C., Chapin, F. S., Matson, P. A., Turner, B. L., Agrawal, A., Crutzen, P. J., Field, C., Gleick, P., Kareiva, P. M., Lambin, E., Liverman, D., Ostrom, E., Sanchez, P. A., Syvitski, J. 2012; 62 (6): 603-606

  View details for DOI 10.1525/bio.2012.62.6.11

  View details for Web of Science ID 000305262500011

• Harvesting Carbon from Eastern US Forests: Opportunities and Impacts of an Expanding Bioenergy Industry FORESTS Davis, S. C., Dietze, M., DeLucia, E., Field, C., Hamburg, S. P., Loarie, S., Parton, W., Potts, M., Ramage, B., Wang, D., Youngs, H., Long, S. P. 2012; 3 (2): 370-397

  View details for DOI 10.3390/f3020370

  View details for Web of Science ID 000315414900013

• The roles of hydraulic and carbon stress in a widespread climate-induced forest die-off PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Anderegg, W. R., Berry, J. A., Smith, D. D., Sperry, J. S., Anderegg, L. D., Field, C. B. 2012; 109 (1): 233-237

  Abstract

  Forest ecosystems store approximately 45% of the carbon found in terrestrial ecosystems, but they are sensitive to climate-induced dieback. Forest die-off constitutes a large uncertainty in projections of climate impacts on terrestrial ecosystems, climate-ecosystem interactions, and carbon-cycle feedbacks. Current understanding of the physiological mechanisms mediating climate-induced forest mortality limits the ability to model or project these threshold events. We report here a direct and in situ study of the mechanisms underlying recent widespread and climate-induced trembling aspen (Populus tremuloides) forest mortality in western North America. We find substantial evidence of hydraulic failure of roots and branches linked to landscape patterns of canopy and root mortality in this species. On the contrary, we find no evidence that drought stress led to depletion of carbohydrate reserves. Our results illuminate proximate mechanisms underpinning recent aspen forest mortality and provide guidance for understanding and projecting forest die-offs under climate change.

  View details for DOI 10.1073/pnas.1107891109

  View details for Web of Science ID 000298876500048

  View details for PubMedID 22167807

  View details for PubMedCentralID PMC3252909

• Environmental filtering and land-use history drive patterns in biomass accumulation in a mediterranean-type landscape ECOLOGICAL APPLICATIONS Dahlin, K. M., Asner, G. P., Field, C. B. 2012; 22 (1): 104-118

  Abstract

  Aboveground biomass (AGB) reflects multiple and often undetermined ecological and land-use processes, yet detailed landscape-level studies of AGB are uncommon due to the difficulty in making consistent measurements at ecologically relevant scales. Working in a protected mediterranean-type landscape (Jasper Ridge Biological Preserve, California, USA), we combined field measurements with remotely sensed data from the Carnegie Airborne Observatory's light detection and ranging (lidar) system to create a detailed AGB map. We then developed a predictive model using a maximum of 56 explanatory variables derived from geologic and historic-ownership maps, a digital elevation model, and geographic coordinates to evaluate possible controls over currently observed AGB patterns. We tested both ordinary least-squares regression (OLS) and autoregressive approaches. OLS explained 44% of the variation in AGB, and simultaneous autoregression with a 100-m neighborhood improved the fit to an r2 = 0.72, while reducing the number of significant predictor variables from 27 variables in the OLS model to 11 variables in the autoregressive model. We also compared the results from these approaches to a more typical field-derived data set; we randomly sampled 5% of the data 1000 times and used the same OLS approach each time. Environmental filters including incident solar radiation, substrate type, and topographic position were significant predictors of AGB in all models. Past ownership was a minor but significant predictor, despite the long history of conservation at the site. The weak predictive power of these environmental variables, and the significant improvement when spatial autocorrelation was incorporated, highlight the importance of land-use history, disturbance regime, and population dynamics as controllers of AGB.

  View details for Web of Science ID 000301095600009

  View details for PubMedID 22471078

• Effect of vineyard-scale climate variability on Pinot noir phenolic composition AGRICULTURAL AND FOREST METEOROLOGY Nicholas, K. A., Matthews, M. A., Lobell, D. B., Willits, N. H., Field, C. B. 2011; 151 (12): 1556-1567

  View details for DOI 10.1016/j.agrformet.2011.06.010

  View details for Web of Science ID 000297277200007

• California perennial crops in a changing climate CLIMATIC CHANGE Lobell, D. B., Field, C. B. 2011; 109: 317-333

  View details for DOI 10.1007/s10584-011-0303-6

  View details for Web of Science ID 000298757300016

• Climate extremes in California agriculture CLIMATIC CHANGE Lobell, D. B., Torney, A., Field, C. B. 2011; 109: 355-363

  View details for DOI 10.1007/s10584-011-0304-5

  View details for Web of Science ID 000298757300018

• Native and Non-Native Community Assembly through Edaphic Manipulation: Implications for Habitat Creation and Restoration RESTORATION ECOLOGY Bonebrake, T. C., Navratil, R. T., Boggs, C. L., Fendorf, S., Field, C. B., Ehrlichl, P. R. 2011; 19 (6): 709-716

  View details for DOI 10.1111/j.1526-100X.2010.00768.x

  View details for Web of Science ID 000297078600006

• Strong response of an invasive plant species (Centaurea solstitialis L.) to global environmental changes ECOLOGICAL APPLICATIONS Dukes, J. S., Chiariello, N. R., Loarie, S. R., Field, C. B. 2011; 21 (6): 1887-1894

  Abstract

  Global environmental changes are altering interactions among plant species, sometimes favoring invasive species. Here, we examine how a suite of five environmental factors, singly and in combination, can affect the success of a highly invasive plant. We introduced Centaurea solstitialis L. (yellow starthistle), which is considered by many to be California's most troublesome wildland weed, to grassland plots in the San Francisco Bay Area. These plots experienced ambient or elevated levels of warming, atmospheric CO2, precipitation, and nitrate deposition, and an accidental fire in the previous year created an additional treatment. Centaurea grew more than six times larger in response to elevated CO2, and, outside of the burned area, grew more than three times larger in response to nitrate deposition. In contrast, resident plants in the community responded less strongly (or did not respond) to these treatments. Interactive effects among treatments were rarely significant. Results from a parallel mesocosm experiment, while less dramatic, supported the pattern of results observed in the field. Taken together, our results suggest that ongoing environmental changes may dramatically increase Centaurea's prevalence in western North America.

  View details for Web of Science ID 000294155900001

  View details for PubMedID 21939031

• Forest biomass allometry in global land surface models GLOBAL BIOGEOCHEMICAL CYCLES Wolf, A., Ciais, P., Bellassen, V., Delbart, N., Field, C. B., Berry, J. A. 2011; 25

  View details for DOI 10.1029/2010GB003917

  View details for Web of Science ID 000293922200001

• Allometric growth and allocation in forests: a perspective from FLUXNET ECOLOGICAL APPLICATIONS Wolf, A., Field, C. B., Berry, J. A. 2011; 21 (5): 1546-1556

  Abstract

  To develop a scheme for partitioning the products of photosynthesis toward different biomass components in land-surface models, a database on component mass and net primary productivity (NPP), collected from FLUXNET sites, was examined to determine allometric patterns of allocation. We found that NPP per individual of foliage (Gfol), stem and branches (Gstem), coarse roots (Gcroot) and fine roots (Gfroot) in individual trees is largely explained (r2 = 67-91%) by the magnitude of total NPP per individual (G). Gfol scales with G isometrically, meaning it is a fixed fraction of G ( 25%). Root-shoot trade-offs were manifest as a slow decline in Gfroot, as a fraction of G, from 50% to 25% as stands increased in biomass, with Gstem and Gcroot increasing as a consequence. These results indicate that a functional trade-off between aboveground and belowground allocation is essentially captured by variations in G, which itself is largely governed by stand biomass and only secondarily by site-specific resource availability. We argue that forests are characterized by strong competition for light, observed as a race for individual trees to ascend by increasing partitioning toward wood, rather than by growing more leaves, and that this competition stronglyconstrains the allocational plasticity that trees may be capable of. The residual variation in partitioning was not related to climatic or edaphic factors, nor did plots with nutrient or water additions show a pattern of partitioning distinct from that predicted by G alone. These findings leverage short-term process studies of the terrestrial carbon cycle to improve decade-scale predictions of biomass accumulation in forests. An algorithm for calculating partitioning in land-surface models is presented.

  View details for Web of Science ID 000292766100010

  View details for PubMedID 21830701

• Global Change Could Amplify Fire Effects on Soil Greenhouse Gas Emissions PLOS ONE Niboyet, A., Brown, J. R., Dijkstra, P., Blankinship, J. C., Leadley, P. W., Le Roux, X., Barthes, L., Barnard, R. L., Field, C. B., Hungate, B. A. 2011; 6 (6)

  Abstract

  Little is known about the combined impacts of global environmental changes and ecological disturbances on ecosystem functioning, even though such combined impacts might play critical roles in shaping ecosystem processes that can in turn feed back to climate change, such as soil emissions of greenhouse gases.We took advantage of an accidental, low-severity wildfire that burned part of a long-term global change experiment to investigate the interactive effects of a fire disturbance and increases in CO(2) concentration, precipitation and nitrogen supply on soil nitrous oxide (N(2)O) emissions in a grassland ecosystem. We examined the responses of soil N(2)O emissions, as well as the responses of the two main microbial processes contributing to soil N(2)O production--nitrification and denitrification--and of their main drivers. We show that the fire disturbance greatly increased soil N(2)O emissions over a three-year period, and that elevated CO(2) and enhanced nitrogen supply amplified fire effects on soil N(2)O emissions: emissions increased by a factor of two with fire alone and by a factor of six under the combined influence of fire, elevated CO(2) and nitrogen. We also provide evidence that this response was caused by increased microbial denitrification, resulting from increased soil moisture and soil carbon and nitrogen availability in the burned and fertilized plots.Our results indicate that the combined effects of fire and global environmental changes can exceed their effects in isolation, thereby creating unexpected feedbacks to soil greenhouse gas emissions. These findings highlight the need to further explore the impacts of ecological disturbances on ecosystem functioning in the context of global change if we wish to be able to model future soil greenhouse gas emissions with greater confidence.

  View details for DOI 10.1371/journal.pone.0020105

  View details for Web of Science ID 000291611500008

  View details for PubMedID 21687708

  View details for PubMedCentralID PMC3110610

• Direct impacts on local climate of sugar-cane expansion in Brazil NATURE CLIMATE CHANGE Loarie, S. R., Lobell, D. B., Asner, G. P., Mu, Q., Field, C. B. 2011; 1 (2): 105-109

  View details for DOI 10.1038/NCLIMATE1067

  View details for Web of Science ID 000293718200028

• Testing interactive effects of global environmental changes on soil nitrogen cycling ECOSPHERE Niboyet, A., Le Roux, X., Dijkstra, P., Hungate, B. A., Barthes, L., Blankinship, J. C., Brown, J. R., Field, C. B., Leadley, P. W. 2011; 2 (5)

  View details for DOI 10.1890/ES10-00148.1

  View details for Web of Science ID 000208810600004

• Direct climate effects of perennial bioenergy crops in the United States PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Georgescu, M., Lobell, D. B., Field, C. B. 2011; 108 (11): 4307-4312

  Abstract

  Biomass-derived energy offers the potential to increase energy security while mitigating anthropogenic climate change, but a successful path toward increased production requires a thorough accounting of costs and benefits. Until recently, the efficacy of biomass-derived energy has focused primarily on biogeochemical consequences. Here we show that the biogeophysical effects that result from hypothetical conversion of annual to perennial bioenergy crops across the central United States impart a significant local to regional cooling with considerable implications for the reservoir of stored soil water. This cooling effect is related mainly to local increases in transpiration, but also to higher albedo. The reduction in radiative forcing from albedo alone is equivalent to a carbon emissions reduction of , which is six times larger than the annual biogeochemical effects that arise from offsetting fossil fuel use. Thus, in the near-term, the biogeophysical effects are an important aspect of climate impacts of biofuels, even at the global scale. Locally, the simulated cooling is sufficiently large to partially offset projected warming due to increasing greenhouse gases over the next few decades. These results demonstrate that a thorough evaluation of costs and benefits of bioenergy-related land-use change must include potential impacts on the surface energy and water balance to comprehensively address important concerns for local, regional, and global climate change.

  View details for DOI 10.1073/pnas.1008779108

  View details for Web of Science ID 000288450900015

  View details for PubMedID 21368189

• Land-Cover and Surface Water Change Drive Large Albedo Increases in South America EARTH INTERACTIONS Loarie, S. R., Lobell, D. B., Asner, G. P., Field, C. B. 2011; 15

  View details for DOI 10.1175/2010EI342.1

  View details for Web of Science ID 000291146600001

• Coordinated approaches to quantify long-term ecosystem dynamics in response to global change GLOBAL CHANGE BIOLOGY Luo, Y., Melillo, J., Niu, S., Beier, C., Clark, J. S., Classen, A. T., Davidson, E., Dukes, J. S., Evans, R. D., Field, C. B., Czimczik, C. I., Keller, M., Kimball, B. A., Kueppers, L. M., Norby, R. J., Pelini, S. L., Pendall, E., Rastetter, E., Six, J., Smith, M., Tjoelker, M. G., Torn, M. S. 2011; 17 (2): 843-854

  View details for DOI 10.1111/j.1365-2486.2010.02265.x

  View details for Web of Science ID 000285878000015

• Agricultural net primary production in relation to that liberated by the extinction of Pleistocene mega-herbivores: an estimate of agricultural carrying capacity? ENVIRONMENTAL RESEARCH LETTERS Doughty, C. E., Field, C. B. 2010; 5 (4)

  View details for DOI 10.1088/1748-9326/5/4/044001

  View details for Web of Science ID 000286420700003

• Biophysical feedbacks between the Pleistocene megafauna extinction and climate: The first human-induced global warming? GEOPHYSICAL RESEARCH LETTERS Doughty, C. E., Wolf, A., Field, C. B. 2010; 37

  View details for DOI 10.1029/2010GL043985

  View details for Web of Science ID 000280718200007

• Nutrient Limitations of Carbon Uptake: From Leaves to Landscapes in a California Rangeland Ecosystem RANGELAND ECOLOGY & MANAGEMENT Houlton, B. Z., Field, C. B. 2010; 63 (1): 120-127

  View details for DOI 10.2111/REM-D-09-00098.1

  View details for Web of Science ID 000274112700011

• The velocity of climate change NATURE Loarie, S. R., Duffy, P. B., Hamilton, H., Asner, G. P., Field, C. B., Ackerly, D. D. 2009; 462 (7276): 1052-U111

  Abstract

  The ranges of plants and animals are moving in response to recent changes in climate. As temperatures rise, ecosystems with 'nowhere to go', such as mountains, are considered to be more threatened. However, species survival may depend as much on keeping pace with moving climates as the climate's ultimate persistence. Here we present a new index of the velocity of temperature change (km yr(-1)), derived from spatial gradients ( degrees C km(-1)) and multimodel ensemble forecasts of rates of temperature increase ( degrees C yr(-1)) in the twenty-first century. This index represents the instantaneous local velocity along Earth's surface needed to maintain constant temperatures, and has a global mean of 0.42 km yr(-1) (A1B emission scenario). Owing to topographic effects, the velocity of temperature change is lowest in mountainous biomes such as tropical and subtropical coniferous forests (0.08 km yr(-1)), temperate coniferous forest, and montane grasslands. Velocities are highest in flooded grasslands (1.26 km yr(-1)), mangroves and deserts. High velocities suggest that the climates of only 8% of global protected areas have residence times exceeding 100 years. Small protected areas exacerbate the problem in Mediterranean-type and temperate coniferous forest biomes. Large protected areas may mitigate the problem in desert biomes. These results indicate management strategies for minimizing biodiversity loss from climate change. Montane landscapes may effectively shelter many species into the next century. Elsewhere, reduced emissions, a much expanded network of protected areas, or efforts to increase species movement may be necessary.

  View details for DOI 10.1038/nature08649

  View details for Web of Science ID 000272996000046

  View details for PubMedID 20033047

• Potential impact of US biofuels on regional climate GEOPHYSICAL RESEARCH LETTERS Georgescu, M., Lobell, D. B., Field, C. B. 2009; 36

  View details for DOI 10.1029/2009GL040477

  View details for Web of Science ID 000271847900001

• Boosted carbon emissions from Amazon deforestation GEOPHYSICAL RESEARCH LETTERS Loarie, S. R., Asner, G. P., Field, C. B. 2009; 36

  View details for DOI 10.1029/2009GL037526

  View details for Web of Science ID 000268349500002

• Greater Transportation Energy and GHG Offsets from Bioelectricity Than Ethanol SCIENCE Campbell, J. E., Lobell, D. B., Field, C. B. 2009; 324 (5930): 1055-1057

  Abstract

  The quantity of land available to grow biofuel crops without affecting food prices or greenhouse gas (GHG) emissions from land conversion is limited. Therefore, bioenergy should maximize land-use efficiency when addressing transportation and climate change goals. Biomass could power either internal combustion or electric vehicles, but the relative land-use efficiency of these two energy pathways is not well quantified. Here, we show that bioelectricity outperforms ethanol across a range of feedstocks, conversion technologies, and vehicle classes. Bioelectricity produces an average of 81% more transportation kilometers and 108% more emissions offsets per unit area of cropland than does cellulosic ethanol. These results suggest that alternative bioenergy pathways have large differences in how efficiently they use the available land to achieve transportation and climate goals.

  View details for DOI 10.1126/science.1168885

  View details for Web of Science ID 000266246700037

  View details for PubMedID 19423776

• Crop Yield Gaps: Their Importance, Magnitudes, and Causes ANNUAL REVIEW OF ENVIRONMENT AND RESOURCES Lobell, D. B., Cassman, K. G., Field, C. B. 2009; 34: 179-204

  View details for DOI 10.1146/annurev.environ.041008.093740

  View details for Web of Science ID 000272082000009

• Responses of a California annual grassland to litter manipulation JOURNAL OF VEGETATION SCIENCE Amatangelo, K. L., Dukes, J. S., Field, C. B. 2008; 19 (5): 605-612

  View details for DOI 10.3170/2008-8-18415

  View details for Web of Science ID 000255199300003

• Protecting climate with forests ENVIRONMENTAL RESEARCH LETTERS Jackson, R. B., Randerson, J. T., Canadell, J. G., Anderson, R. G., Avissar, R., Baldocchi, D. D., Bonan, G. B., Caldeira, K., Diffenbaugh, N. S., Field, C. B., Hungate, B. A., Jobbagy, E. G., Kueppers, L. M., Nosetto, M. D., Pataki, D. E. 2008; 3 (4)

  View details for DOI 10.1088/1748-9326/3/4/044006

  View details for Web of Science ID 000265878400006

• Vulnerability of permafrost carbon to climate change: Implications for the global carbon cycle BIOSCIENCE Schuur, E. A., Bockheim, J., Canadell, J. G., Euskirchen, E., Field, C. B., Goryachkin, S. V., Hagemann, S., Kuhry, P., Lafleur, P. M., Lee, H., Mazhitova, G., Nelson, F. E., Rinke, A., Romanovsky, V. E., Shiklomanov, N., Tarnocai, C., Venevsky, S., Vogel, J. G., Zimov, S. A. 2008; 58 (8): 701-714

  View details for DOI 10.1641/B580807

  View details for Web of Science ID 000259058100009

• The global potential of bioenergy on abandoned agriculture lands ENVIRONMENTAL SCIENCE & TECHNOLOGY Campbell, J. E., Lobell, D. B., Genova, R. C., Field, C. B. 2008; 42 (15): 5791-5794

  Abstract

  Converting forest lands into bioenergy agriculture could accelerate climate change by emitting carbon stored in forests, while converting food agriculture lands into bioenergy agriculture could threaten food security. Both problems are potentially avoided by using abandoned agriculture lands for bioenergy agriculture. Here we show the global potential for bioenergy on abandoned agriculture lands to be less than 8% of current primary energy demand, based on historical land use data, satellite-derived land cover data, and global ecosystem modeling. The estimated global area of abandoned agriculture is 385-472 million hectares, or 66-110% of the areas reported in previous preliminary assessments. The area-weighted mean production of above-ground biomass is 4.3 tons ha(-1) y(-1), in contrast to estimates of up to 10 tons ha(-1) y(-1) in previous assessments. The energy content of potential biomass grown on 100% of abandoned agriculture lands is less than 10% of primary energy demand for most nations in North America, Europe, and Asia, but it represents many times the energy demand in some African nations where grasslands are relatively productive and current energy demand is low.

  View details for DOI 10.1021/es800052w

  View details for Web of Science ID 000258075100065

  View details for PubMedID 18754510

• Accentuation of phosphorus limitation in Geranium dissectum by nitrogen: an ecological genomics study GLOBAL CHANGE BIOLOGY Thayer, S. S., St Clair, S. B., Field, C. B., Somerville, S. C. 2008; 14 (8): 1877-1890

  View details for DOI 10.1111/j.1365-2486.2008.01618.x

  View details for Web of Science ID 000257712400012

• Changing feedbacks in the climate-biosphere system FRONTIERS IN ECOLOGY AND THE ENVIRONMENT Chapin, F. S., Randerson, J. T., McGuire, A. D., Foley, J. A., Field, C. B. 2008; 6 (6): 313-320

  View details for DOI 10.1890/080005

  View details for Web of Science ID 000258249200017

• A unifying framework for dinitrogen fixation in the terrestrial biosphere NATURE Houlton, B. Z., Wang, Y., Vitousek, P. M., Field, C. B. 2008; 454 (7202): 327-U34

  Abstract

  Dinitrogen (N(2)) fixation is widely recognized as an important process in controlling ecosystem responses to global environmental change, both today and in the past; however, significant discrepancies exist between theory and observations of patterns of N(2) fixation across major sectors of the land biosphere. A question remains as to why symbiotic N(2)-fixing plants are more abundant in vast areas of the tropics than in many of the mature forests that seem to be nitrogen-limited in the temperate and boreal zones. Here we present a unifying framework for terrestrial N(2) fixation that can explain the geographic occurrence of N(2) fixers across diverse biomes and at the global scale. By examining trade-offs inherent in plant carbon, nitrogen and phosphorus capture, we find a clear advantage to symbiotic N(2) fixers in phosphorus-limited tropical savannas and lowland tropical forests. The ability of N(2) fixers to invest nitrogen into phosphorus acquisition seems vital to sustained N(2) fixation in phosphorus-limited tropical ecosystems. In contrast, modern-day temperatures seem to constrain N(2) fixation rates and N(2)-fixing species from mature forests in the high latitudes. We propose that an analysis that couples biogeochemical cycling and biophysical mechanisms is sufficient to explain the principal geographical patterns of symbiotic N(2) fixation on land, thus providing a basis for predicting the response of nutrient-limited ecosystems to climate change and increasing atmospheric CO(2).

  View details for DOI 10.1038/nature07028

  View details for Web of Science ID 000257665300037

  View details for PubMedID 18563086

• Litter decomposition in a california annual grassland: Interactions between photodegradation and litter layer thickness ECOSYSTEMS Henry, H. A., Brizgys, K., Field, C. B. 2008; 11 (4): 545-554

  View details for DOI 10.1007/s10021-008-9141-4

  View details for Web of Science ID 000256529200004

• Energy assumptions were reasonable at the time, but not now NATURE Field, C. B. 2008; 453 (7192): 154-155

  View details for DOI 10.1038/453154b

  View details for Web of Science ID 000255592400013

  View details for PubMedID 18464715

• Biomass energy: the scale of the potential resource TRENDS IN ECOLOGY & EVOLUTION Field, C. B., Campbell, J. E., Lobell, D. B. 2008; 23 (2): 65-72

  Abstract

  Increased production of biomass for energy has the potential to offset substantial use of fossil fuels, but it also has the potential to threaten conservation areas, pollute water resources and decrease food security. The net effect of biomass energy agriculture on climate could be either cooling or warming, depending on the crop, the technology for converting biomass into useable energy, and the difference in carbon stocks and reflectance of solar radiation between the biomass crop and the pre-existing vegetation. The area with the greatest potential for yielding biomass energy that reduces net warming and avoids competition with food production is land that was previously used for agriculture or pasture but that has been abandoned and not converted to forest or urban areas. At the global scale, potential above-ground plant growth on these abandoned lands has an energy content representing approximately 5% of world primary energy consumption in 2006. The global potential for biomass energy production is large in absolute terms, but it is not enough to replace more than a few percent of current fossil fuel usage. Increasing biomass energy production beyond this level would probably reduce food security and exacerbate forcing of climate change.

  View details for DOI 10.1016/j.tree.2007.12.001

  View details for Web of Science ID 000253620000004

  View details for PubMedID 18215439

• Estimation of the carbon dioxide (CO2) fertilization effect using growth rate anomalies of CO2 and crop yields since 1961 GLOBAL CHANGE BIOLOGY Lobell, D. B., Field, C. B. 2008; 14 (1): 39-45

  View details for DOI 10.1111/j.1365-2486.2007.01476.x

  View details for Web of Science ID 000251415000004

• Simulated global changes alter phosphorus demand in annual grassland GLOBAL CHANGE BIOLOGY Menge, D. N., Field, C. B. 2007; 13 (12): 2582-2591

  View details for DOI 10.1111/j.1365-2486.2007.01456.x

  View details for Web of Science ID 000251049000008

• Contributions to accelerating atmospheric CO2 growth from economic activity, carbon intensity, and efficiency of natural sinks PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Canadell, J. G., Le Quere, C., Raupach, M. R., Field, C. B., Buitenhuis, E. T., Ciais, P., Conway, T. J., Gillett, N. P., Houghton, R. A., Marland, G. 2007; 104 (47): 18866-18870

  Abstract

  The growth rate of atmospheric carbon dioxide (CO(2)), the largest human contributor to human-induced climate change, is increasing rapidly. Three processes contribute to this rapid increase. Two of these processes concern emissions. Recent growth of the world economy combined with an increase in its carbon intensity have led to rapid growth in fossil fuel CO(2) emissions since 2000: comparing the 1990s with 2000-2006, the emissions growth rate increased from 1.3% to 3.3% y(-1). The third process is indicated by increasing evidence (P = 0.89) for a long-term (50-year) increase in the airborne fraction (AF) of CO(2) emissions, implying a decline in the efficiency of CO(2) sinks on land and oceans in absorbing anthropogenic emissions. Since 2000, the contributions of these three factors to the increase in the atmospheric CO(2) growth rate have been approximately 65 +/- 16% from increasing global economic activity, 17 +/- 6% from the increasing carbon intensity of the global economy, and 18 +/- 15% from the increase in AF. An increasing AF is consistent with results of climate-carbon cycle models, but the magnitude of the observed signal appears larger than that estimated by models. All of these changes characterize a carbon cycle that is generating stronger-than-expected and sooner-than-expected climate forcing.

  View details for DOI 10.1073/pnas.0702737104

  View details for Web of Science ID 000251292500092

  View details for PubMedID 17962418

• Global and regional drivers of accelerating CO2 emissions PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Raupach, M. R., Marland, G., Ciais, P., Le Quere, C., Canadell, J. G., Klepper, G., Field, C. B. 2007; 104 (24): 10288-10293

  Abstract

  CO2 emissions from fossil-fuel burning and industrial processes have been accelerating at a global scale, with their growth rate increasing from 1.1% y(-1) for 1990-1999 to >3% y(-1) for 2000-2004. The emissions growth rate since 2000 was greater than for the most fossil-fuel intensive of the Intergovernmental Panel on Climate Change emissions scenarios developed in the late 1990s. Global emissions growth since 2000 was driven by a cessation or reversal of earlier declining trends in the energy intensity of gross domestic product (GDP) (energy/GDP) and the carbon intensity of energy (emissions/energy), coupled with continuing increases in population and per-capita GDP. Nearly constant or slightly increasing trends in the carbon intensity of energy have been recently observed in both developed and developing regions. No region is decarbonizing its energy supply. The growth rate in emissions is strongest in rapidly developing economies, particularly China. Together, the developing and least-developed economies (forming 80% of the world's population) accounted for 73% of global emissions growth in 2004 but only 41% of global emissions and only 23% of global cumulative emissions since the mid-18th century. The results have implications for global equity.

  View details for DOI 10.1073/pnas.0700609104

  View details for Web of Science ID 000247363000066

  View details for PubMedID 17519334

• Environment. Tropical forests and climate policy. Science Gullison, R. E., Frumhoff, P. C., Canadell, J. G., Field, C. B., Nepstad, D. C., Hayhoe, K., Avissar, R., Curran, L. M., Friedlingstein, P., Jones, C. D., Nobre, C. 2007; 316 (5827): 985-986

  View details for PubMedID 17495140

• Responses of temporal distribution of gastropods to individual and combined effects of elevated CO2 and N deposition in annual grassland ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY Peters, H. A., Hsu, G., Cleland, E. E., Chiariello, N. R., Mooney, H. A., Field, C. B. 2007; 31 (3): 343-352

  View details for DOI 10.1016/j.actao.2007.01.005

  View details for Web of Science ID 000246909800013

• A model of biogeochemical cycles of carbon, nitrogen, and phosphorus including symbiotic nitrogen fixation and phosphatase production GLOBAL BIOGEOCHEMICAL CYCLES Wang, Y., Houlton, B. Z., Field, C. B. 2007; 21 (1)

  View details for DOI 10.1029/2006GB002797

  View details for Web of Science ID 000245016700005

• Historical effects of temperature and precipitation on California crop yields CLIMATIC CHANGE Lobell, D. B., Cahill, K. N., Field, C. B. 2007; 81 (2): 187-203

  View details for DOI 10.1007/s10584-006-9141-3

  View details for Web of Science ID 000244685100003

• Feedbacks of terrestrial ecosystems to climate change ANNUAL REVIEW OF ENVIRONMENT AND RESOURCES Field, C. B., Lobell, D. B., Peters, H. A., Chiariello, N. R. 2007; 32: 1-29

  View details for DOI 10.1146/annurev.energy.32.053006.141119

  View details for Web of Science ID 000251280300002

• Carnegie Airborne Observatory: in-flight fusion of hyperspectral imaging and waveform light detection and ranging (wLiDAR) for three-dimensional studies of ecosystems JOURNAL OF APPLIED REMOTE SENSING Asner, G. P., Knapp, D. E., Kennedy-Bowdoin, T., Jones, M. O., Martin, R. E., Boardman, J., Field, C. B. 2007; 1

  View details for DOI 10.1117/1.2794018

  View details for Web of Science ID 000260914300014

• North America Climate Change 2007: Impacts, Adaptation and Vulnerability Field, C. B., Mortsch, L. D., Brklacich, M., Forbes, D. L., Kovacs, P., Patz, J. A., Running, S. W., Scott , M. J. edited by Parry, O. F., Canziani, J. P., Palutikof, P. J., Linden, v. d., Hanson, C. E. Cambridge University Press, Cambridge. 2007
• The carbon cycle of North America in a global context The First State of the Carbon Cycle Report (SOCCR)-Synthesis and Assessment Product 2.2, Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. National Oceanic and Atmospheric Administration Field, C. B., Sarmiento, J., Hales, B. edited by King, A. W., Dilling, L., Zimmerman, G. P., Fairman, D. M., Houghton, R. A., Marland, G., Rose, A. Z., Wilbanks, T. J. National Oceanic and Atmospheric Administration, National Climatic Data Center, Asheville, NC.. 2007: 21–28
• Modeling climate and climate change impacts on winegrape yields in california Cahill, K. N., Lobell, D. B., Field, C. B., Bonfils, C., Hayhoe, K. AMER SOC ENOLOGY VITICULTURE. 2007: 414A–414A

  View details for Web of Science ID 000250219900038

• Global scale climate - crop yield relationships and the impacts of recent warming ENVIRONMENTAL RESEARCH LETTERS Lobell, D. B., Field, C. B. 2007; 2 (1)

  View details for DOI 10.1088/1748-9326/2/1/014002

  View details for Web of Science ID 000253652700004

• Impacts of future climate change on California perennial crop yields: Model projections with climate and crop uncertainties AGRICULTURAL AND FOREST METEOROLOGY Lobell, D. B., Field, C. B., Cahill, K. N., Bonfils, C. 2006; 141 (2-4): 208-218

  View details for DOI 10.1016/j.agrformet.2006.10.006

  View details for Web of Science ID 000243669500010

• Interactive effects of fire, elevated carbon dioxide, nitrogen deposition, and precipitation on a California annual grassland ECOSYSTEMS Henry, H. A., Chiariello, N. R., Vitousek, P. M., Mooney, H. A., Field, C. B. 2006; 9 (7): 1066-1075

  View details for DOI 10.1007/s10021-005-0077-7

  View details for Web of Science ID 000242334600003

• Carbon sequestration in California agriculture, 1980-2000 ECOLOGICAL APPLICATIONS Kroodsma, D. A., Field, C. B. 2006; 16 (5): 1975-1985

  Abstract

  To better understand agricultural carbon fluxes in California, USA, we estimated changes in soil carbon and woody material between 1980 and 2000 on 3.6 x 10(6) ha of farmland in California. Combining the CASA (Carnegie-Ames-Stanford Approach) model with data on harvest indices and yields, we calculated net primary production, woody production in orchard and vineyard crops, and soil carbon. Over the 21-yr period, two trends resulted in carbon sequestration. Yields increased an average of 20%, corresponding to greater plant biomass and more carbon returned to the soils. Also, orchards and vineyards increased in area from 0.7 x 10(6) ha to 1.0 x 10(6) ha, displacing field crops and sequestering woody carbon. Our model estimates that California's agriculture sequestered an average of 19 g C x m(-2) x yr(-1). Sequestration was lowest in non-rice annual cropland, which sequestered 9 g C x m(-2) x yr(-1) of soil carbon, and highest on land that switched from annual cropland to perennial cropland. Land that switched from annual crops to vineyards sequestered 68 g C x m(-2) x yr(-1), and land that switched from annual crops to orchards sequestered 85 g C x m(-2) x yr(-1). Rice fields, because of a reduction in field burning, sequestered 55 g C x m(-2) x yr(-1) in the 1990s. Over the 21 years, California's 3.6 x 10(6) ha of agricultural land sequestered 11.0 Tg C within soils and 3.5 Tg C in woody biomass, for a total of 14.5 Tg C statewide. This is equal to 0.7% of the state's total fossil fuel emissions over the same time period. If California's agriculture adopted conservation tillage, changed management of almond and walnut prunings, and used all of its orchard and vineyard waste wood in the biomass power plants in the state, California's agriculture could offset up to 1.6% of the fossil fuel emissions in the state.

  View details for Web of Science ID 000241362400031

  View details for PubMedID 17069388

• Diverse responses of phenology to global changes in a grassland ecosystem PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Cleland, E. E., Chiariello, N. R., Loarie, S. R., Mooney, H. A., Field, C. B. 2006; 103 (37): 13740-13744

  Abstract

  Shifting plant phenology (i.e., timing of flowering and other developmental events) in recent decades establishes that species and ecosystems are already responding to global environmental change. Earlier flowering and an extended period of active plant growth across much of the northern hemisphere have been interpreted as responses to warming. However, several kinds of environmental change have the potential to influence the phenology of flowering and primary production. Here, we report shifts in phenology of flowering and canopy greenness (Normalized Difference Vegetation Index) in response to four experimentally simulated global changes: warming, elevated CO(2), nitrogen (N) deposition, and increased precipitation. Consistent with previous observations, warming accelerated both flowering and greening of the canopy, but phenological responses to the other global change treatments were diverse. Elevated CO(2) and N addition delayed flowering in grasses, but slightly accelerated flowering in forbs. The opposing responses of these two important functional groups decreased their phenological complementarity and potentially increased competition for limiting soil resources. At the ecosystem level, timing of canopy greenness mirrored the flowering phenology of the grasses, which dominate primary production in this system. Elevated CO(2) delayed greening, whereas N addition dampened the acceleration of greening caused by warming. Increased precipitation had no consistent impacts on phenology. This diversity of phenological changes, between plant functional groups and in response to multiple environmental changes, helps explain the diversity in large-scale observations and indicates that changing temperature is only one of several factors reshaping the seasonality of ecosystem processes.

  View details for DOI 10.1073/pnas.0600815103

  View details for Web of Science ID 000240648300035

  View details for PubMedID 16954189

  View details for PubMedCentralID PMC1560087

• Regression tools for CO2 inversions: application of a shrinkage estimator to process attribution TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY Shaby, B. A., Field, C. B. 2006; 58 (4): 279-292

  View details for DOI 10.1111/j.1600-0889.2006.00189.x

  View details for Web of Science ID 000240334800002

• Gastropod herbivory in response to elevated CO2 and N addition impacts plant community composition ECOLOGY Cleland, E. E., Peters, H. A., Mooney, H. A., Field, C. B. 2006; 87 (3): 686-694

  Abstract

  In this study, the influence of elevated carbon dioxide (CO2) and nitrogen (N) deposition on gastropod herbivory was investigated for six annual species in a California annual grassland community. These experimentally simulated global changes increased availability of important resources for plant growth, leading to the hypothesis that species with the most positive growth and foliar nutrient responses would experience the greatest increase in herbivory. Counter to the expectations, shifts in tissue N and growth rates caused by N deposition did not predict shifts in herbivore consumption rates. N deposition increased seedling N concentrations and growth rates but did not increase herbivore consumption overall, or for any individual species. Elevated CO2 did not influence growth rates nor have a statistically significant influence on seedling N concentrations. Elevated CO2 at ambient N levels caused a decline in the number of seedlings consumed, but the interaction between CO2 and N addition differed among species. The results of this study indicate that shifting patterns of herbivory will likely influence species composition as environmental conditions change in the future; however, a simple trade-off between shifting growth rates and palatability is not evident.

  View details for Web of Science ID 000236289600017

  View details for PubMedID 16602298

• The effects of elevated atmospheric CO2 on the amount and depth distribution of plant water uptake in a California annual grassland GLOBAL CHANGE BIOLOGY Moore, L. A., Field, C. B. 2006; 12 (3): 578-587

  View details for DOI 10.1111/j.1365-2486.2006.01105.x

  View details for Web of Science ID 000236023000015

• Is carbon within the global terrestrial biosphere becoming more oxidized? Implications for trends in atmospheric O-2 GLOBAL CHANGE BIOLOGY Randerson, J. T., Masiello, C. A., Still, C. J., Rahn, T., Poorter, H., Field, C. B. 2006; 12 (2): 260-271

  View details for DOI 10.1111/j.1365-2486.2006.01099.x

  View details for Web of Science ID 000234974900010

• Herbivore control of annual grassland composition in current and future environments ECOLOGY LETTERS Peters, H. A., Cleland, E. E., Mooney, H. A., Field, C. B. 2006; 9 (1): 86-94

  Abstract

  Selective consumption by herbivores influences the composition and structure of a range of plant communities. Anthropogenically driven global environmental changes, including increased atmospheric carbon dioxide (CO(2)), warming, increased precipitation, and increased N deposition, directly alter plant physiological properties, which may in turn modify herbivore consumption patterns. In this study, we tested the hypothesis that responses of annual grassland composition to global changes can be predicted exclusively from environmentally induced changes in the consumption patterns of a group of widespread herbivores, the terrestrial gastropods. This was done by: (1) assessing gastropod impacts on grassland composition under ambient conditions; (2) quantifying environmentally induced changes in gastropod feeding behaviour; (3) predicting how grassland composition would respond to global-change manipulations if influenced only by herbivore consumption preferences; and (4) comparing these predictions to observed responses of grassland community composition to simulated global changes. Gastropod herbivores consume nearly half of aboveground production in this system. Global changes induced species-specific changes in plant leaf characteristics, leading gastropods to alter the relative amounts of different plant types consumed. These changes in gastropod feeding preferences consistently explained global-change-induced responses of functional group abundance in an intact annual grassland exposed to simulated future environments. For four of the five global change scenarios, gastropod impacts explained > 50% of the quantitative changes, indicating that herbivore preferences can be a major driver of plant community responses to global changes.

  View details for DOI 10.1111/j.1461-0248.2005.00847.x

  View details for Web of Science ID 000235306400012

  View details for PubMedID 16958872

• Responses of grassland production to single and multiple global environmental changes PLOS BIOLOGY Dukes, J. S., Chiariello, N. R., Cleland, E. E., Moore, L. A., Shaw, M. R., Thayer, S., Tobeck, T., Mooney, H. A., Field, C. B. 2005; 3 (10): 1829-1837

  Abstract

  In this century, increasing concentrations of carbon dioxide (CO2) and other greenhouse gases in the Earth's atmosphere are expected to cause warmer surface temperatures and changes in precipitation patterns. At the same time, reactive nitrogen is entering natural systems at unprecedented rates. These global environmental changes have consequences for the functioning of natural ecosystems, and responses of these systems may feed back to affect climate and atmospheric composition. Here, we report plant growth responses of an ecosystem exposed to factorial combinations of four expected global environmental changes. We exposed California grassland to elevated CO2, temperature, precipitation, and nitrogen deposition for five years. Root and shoot production did not respond to elevated CO2 or modest warming. Supplemental precipitation led to increases in shoot production and offsetting decreases in root production. Supplemental nitrate deposition increased total production by an average of 26%, primarily by stimulating shoot growth. Interactions among the main treatments were rare. Together, these results suggest that production in this grassland will respond minimally to changes in CO2 and winter precipitation, and to small amounts of warming. Increased nitrate deposition would have stronger effects on the grassland. Aside from this nitrate response, expectations that a changing atmosphere and climate would promote carbon storage by increasing plant growth appear unlikely to be realized in this system.

  View details for DOI 10.1371/journal.pbio.0030319

  View details for Web of Science ID 000232404600016

  View details for PubMedID 16076244

• Interactive effects of elevated CO2, N deposition and climate change on extracellular enzyme activity and soil density fractionation in a California annual grassland GLOBAL CHANGE BIOLOGY Henry, H. A., Juarez, J. D., Field, C. B., Vitousek, P. M. 2005; 11 (10): 1808-1815

  View details for Web of Science ID 000232390200022

• A technique for identifying the roots of different species in mixed samples using nuclear ribosomal DNA JOURNAL OF VEGETATION SCIENCE Moore, L. A., Field, C. B. 2005; 16 (1): 131-134

  View details for Web of Science ID 000228391900015

• Interactive effects of elevated CO2, N deposition and climate change on plant litter quality in a California annual grassland OECOLOGIA Henry, H. A., Cleland, E. E., Field, C. B., Vitousek, P. M. 2005; 142 (3): 465-473

  Abstract

  Although global changes can alter ecosystem nutrient dynamics indirectly as a result of their effects on plant litter quality, the interactive effects of global changes on plant litter remain largely unexplored in natural communities. We investigated the effects of elevated CO2, N deposition, warming and increased precipitation on the composition of organic compounds in plant litter in a fully-factorial experiment conducted in a California annual grassland. While lignin increased within functional groups under elevated CO2, this effect was attenuated by warming in grasses and by water additions in forbs. CO2-induced increases in lignin within functional groups also were counteracted by an increase in the relative biomass of forbs, which contained less lignin than grasses. Consequently, there was no net change in the overall lignin content of senesced tissue at the plot level under elevated CO2. Nitrate additions increased N in both grass and forb litter, although this effect was attenuated by water additions. Relative to changes in N within functional groups, changes in functional group dominance had a minor effect on overall litter N at the plot level. Nitrate additions had the strongest effect on decomposition, increasing lignin losses from Avena litter and interacting with water additions to increase decomposition of litter of other grasses. Increases in lignin that resulted from elevated CO2 had no effect on decomposition but elevated CO2 increased N losses from Avena litter. Overall, the interactions among elements of global change were as important as single-factor effects in influencing plant litter chemistry. However, with the exception of variation in N, litter quality had little influence on decomposition over the short term.

  View details for DOI 10.1007/s00442-004-1713-1

  View details for PubMedID 15558326

• Ammonia-oxidizing bacteria respond to multifactorial global change PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Horz, H. P., Barbrook, A., Field, C. B., Bohannan, B. J. 2004; 101 (42): 15136-15141

  Abstract

  Recent studies have demonstrated that multiple co-occurring global changes can alter the abundance, diversity, and productivity of plant communities. Below ground processes, often mediated by soil microorganisms, are central to the response of these communities to global change. Very little is known, however, about the effects of multiple global changes on microbial communities. We examined the response of ammonia-oxidizing bacteria (AOB), microorganisms that mediate the transformation of ammonium into nitrite, to simultaneous increases in atmospheric CO2, precipitation, temperature, and nitrogen deposition, manipulated on the ecosystem level in a California grassland. Both the community structure and abundance of AOB responded to these simulated global changes. Increased nitrogen deposition significantly altered the structure of the ammonia-oxidizing community, consistently shifting the community toward dominance by bacteria most closely related to Nitrosospira sp. 2. This shift was most pronounced when temperature and precipitation were not increased. Total abundance of AOB significantly decreased in response to increased atmospheric CO2. This decrease was most pronounced when precipitation was also increased. Shifts in community composition were associated with increases in nitrification, but changes in abundance were not. These results demonstrate that microbial communities can be consistently altered by global changes and that these changes can have implications for ecosystem function.

  View details for DOI 10.1073/pnas.0406616101

  View details for Web of Science ID 000224688700030

  View details for PubMedID 15469911

  View details for PubMedCentralID PMC524064

• Emissions pathways, climate change, and impacts on California PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Hayhoe, K., Cayan, D., Field, C. B., Frumhoff, P. C., Maurer, E. P., Miller, N. L., Moser, S. C., Schneider, S. H., Cahill, K. N., Cleland, E. E., Dale, L., Drapek, R., Hanemann, R. M., Kalkstein, L. S., Lenihan, J., Lunch, C. K., Neilson, R. P., Sheridan, S. C., Verville, J. H. 2004; 101 (34): 12422-12427

  Abstract

  The magnitude of future climate change depends substantially on the greenhouse gas emission pathways we choose. Here we explore the implications of the highest and lowest Intergovernmental Panel on Climate Change emissions pathways for climate change and associated impacts in California. Based on climate projections from two state-of-the-art climate models with low and medium sensitivity (Parallel Climate Model and Hadley Centre Climate Model, version 3, respectively), we find that annual temperature increases nearly double from the lower B1 to the higher A1fi emissions scenario before 2100. Three of four simulations also show greater increases in summer temperatures as compared with winter. Extreme heat and the associated impacts on a range of temperature-sensitive sectors are substantially greater under the higher emissions scenario, with some interscenario differences apparent before midcentury. By the end of the century under the B1 scenario, heatwaves and extreme heat in Los Angeles quadruple in frequency while heat-related mortality increases two to three times; alpine/subalpine forests are reduced by 50-75%; and Sierra snowpack is reduced 30-70%. Under A1fi, heatwaves in Los Angeles are six to eight times more frequent, with heat-related excess mortality increasing five to seven times; alpine/subalpine forests are reduced by 75-90%; and snowpack declines 73-90%, with cascading impacts on runoff and streamflow that, combined with projected modest declines in winter precipitation, could fundamentally disrupt California's water rights system. Although interscenario differences in climate impacts and costs of adaptation emerge mainly in the second half of the century, they are strongly dependent on emissions from preceding decades.

  View details for DOI 10.1073/pnas.0404500101

  View details for Web of Science ID 000223596200007

  View details for PubMedID 15314227

• The carbon balance of an old-growth forest: Building across approaches ECOSYSTEMS Field, C. B., Kaduk, J. 2004; 7 (5): 525-533

  View details for DOI 10.1007/s10021-004-0142-7

  View details for Web of Science ID 000223266900009

• Progressive nitrogen limitation of ecosystem responses to rising atmospheric carbon dioxide BIOSCIENCE Luo, Y., Su, B., Currie, W. S., Dukes, J. S., Finzi, A. C., Hartwig, U., Hungate, B., McMurtrie, R. E., Oren, R., Parton, W. J., Pataki, D. E., Shaw, M. R., Zak, D. R., Field, C. B. 2004; 54 (8): 731-739

  View details for Web of Science ID 000223146000009

• Atmospheric science. Nitrogen and climate change. Science Hungate, B. A., Dukes, J. S., Shaw, M. R., Luo, Y., Field, C. B. 2003; 302 (5650): 1512-1513

  View details for PubMedID 14645831

• Diurnal centroid of ecosystem energy and carbon fluxes at FLUXNET sites JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES Wilson, K. B., Baldocchi, D., Falge, E., Aubinet, M., Berbigier, P., Bernhofer, C., Dolman, H., Field, C., Goldstein, A., Granier, A., Hollinger, D., Katul, G., Law, B. E., Meyers, T., Moncrieff, J., Monson, R., Tenhunen, J., Valentini, R., Verma, S., Wofsy, S. 2003; 108 (D21)

  View details for DOI 10.1029/2001JD001349

  View details for Web of Science ID 000186508200001

• Grassland responses to three years of elevated temperature, CO2, precipitation, and N deposition ECOLOGICAL MONOGRAPHS Zavaleta, E. S., Shaw, M. R., Chiariello, N. R., Thomas, B. D., Cleland, E. E., Field, C. B., Mooney, H. A. 2003; 73 (4): 585-604

  View details for Web of Science ID 000187291000005

• Plants reverse warming effect on ecosystem water balance PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Zavaleta, E. S., Thomas, B. D., Chiariello, N. R., Asner, G. P., Shaw, M. R., Field, C. B. 2003; 100 (17): 9892-9893

  Abstract

  Models predict that global warming may increase aridity in water-limited ecosystems by accelerating evapotranspiration. We show that interactions between warming and the dominant biota in a grassland ecosystem produced the reverse effect. In a 2-year field experiment, simulated warming increased spring soil moisture by 5-10% under both ambient and elevated CO2. Warming also accelerated the decline of canopy greenness (normalized difference vegetation index) each spring by 11-17% by inducing earlier plant senescence. Lower transpirational water losses resulting from this earlier senescence provide a mechanism for the unexpected rise in soil moisture. Our findings illustrate the potential for organism-environment interactions to modify the direction as well as the magnitude of global change effects on ecosystem functioning.

  View details for DOI 10.1073/pnas.1732012100

  View details for PubMedID 12907704

• Postfire response of North American boreal forest net primary productivity analyzed with satellite observations GLOBAL CHANGE BIOLOGY Hicke, J. A., Asner, G. P., Kasischke, E. S., French, N. H., Randerson, J. T., Collatz, G. J., Stocks, B. J., Tucker, C. J., Los, S. O., Field, C. B. 2003; 9 (8): 1145-1157

  View details for Web of Science ID 000184483200002

• Arbuscular mycorrhizae respond to plants exposed to elevated atmospheric CO2 as a function of soil depth PLANT AND SOIL Rillig, M. C., Field, C. B. 2003; 254 (2): 383-391

  View details for Web of Science ID 000185070900013

• Additive effects of simulated climate changes, elevated CO2, and nitrogen deposition on grassland diversity PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Zavaleta, E. S., Shaw, M. R., Chiariello, N. R., Mooney, H. A., Field, C. B. 2003; 100 (13): 7650-7654

  Abstract

  Biodiversity responses to ongoing climate and atmospheric changes will affect both ecosystem processes and the delivery of ecosystem goods and services. Combined effects of co-occurring global changes on diversity, however, are poorly understood. We examined plant diversity responses in a California annual grassland to manipulations of four global environmental changes, singly and in combination: elevated CO2, warming, precipitation, and nitrogen deposition. After 3 years, elevated CO2 and nitrogen deposition each reduced plant diversity, whereas elevated precipitation increased it and warming had no significant effect. Diversity responses to both single and combined global change treatments were driven overwhelmingly by gains and losses of forb species, which make up most of the native plant diversity in California grasslands. Diversity responses across treatments also showed no consistent relationship to net primary production responses, illustrating that the diversity effects of these environmental changes could not be explained simply by changes in productivity. In two- to four-way combinations, simulated global changes did not interact in any of their effects on diversity. Our results show that climate and atmospheric changes can rapidly alter biological diversity, with combined effects that, at least in some settings, are simple, additive combinations of single-factor effects.

  View details for DOI 10.1073/pnas.0932734100

  View details for Web of Science ID 000183845800045

  View details for PubMedID 12810960

  View details for PubMedCentralID PMC164642

• Temporal evolution of the European forest sector carbon sink from 1950 to 1999 GLOBAL CHANGE BIOLOGY Nabuurs, G. J., Schelhaas, M. J., Mohren, G. M., Field, C. B. 2003; 9 (2): 152-160

  View details for Web of Science ID 000180852800004

• Environmental control of leaf area production: Implications for vegetation and land-surface modeling GLOBAL BIOGEOCHEMICAL CYCLES Cowling, S. A., Field, C. B. 2003; 17 (1)

  View details for DOI 10.1029/2002GL001915

  View details for Web of Science ID 000181544100001

• Element interactions and the cycles of life: An overview Conference on Element Interactions Melillo, J. M., Field, C. B., MOLDAN, B. ISLAND PRESS. 2003: 1–12

  View details for Web of Science ID 000221668200001

• New frontiers in the study of element interactions Conference on Element Interactions Ollinger, S., Sala, O., AGREN, G. I., Berg, B., Davidson, E., Field, C. B., Lerdau, M. T., Neff, J., Scholes, M., Sterner, R. ISLAND PRESS. 2003: 63–91

  View details for Web of Science ID 000221668200004

• Energy partitioning between latent and sensible heat flux during the warm season at FLUXNET sites WATER RESOURCES RESEARCH Wilson, K. B., Baldocchi, D. D., Aubinet, M., Berbigier, P., Bernhofer, C., Dolman, H., Falge, E., Field, C., Goldstein, A., Granier, A., Grelle, A., Halldor, T., Hollinger, D., Katul, G., Law, B. E., Lindroth, A., Meyers, T., Moncrieff, J., Monson, R., Oechel, W., Tenhunen, J., Valentini, R., Verma, S., Vesala, T., Wofsy, S. 2002; 38 (12)

  View details for DOI 10.1029/2001WR000989

  View details for Web of Science ID 000181245200004

• Grassland responses to global environmental changes suppressed by elevated CO2 SCIENCE Shaw, M. R., Zavaleta, E. S., Chiariello, N. R., Cleland, E. E., Mooney, H. A., Field, C. B. 2002; 298 (5600): 1987-1990

  Abstract

  Simulated global changes, including warming, increased precipitation, and nitrogen deposition, alone and in concert, increased net primary production (NPP) in the third year of ecosystem-scale manipulations in a California annual grassland. Elevated carbon dioxide also increased NPP, but only as a single-factor treatment. Across all multifactor manipulations, elevated carbon dioxide suppressed root allocation, decreasing the positive effects of increased temperature, precipitation, and nitrogen deposition on NPP. The NPP responses to interacting global changes differed greatly from simple combinations of single-factor responses. These findings indicate the importance of a multifactor experimental approach to understanding ecosystem responses to global change.

  View details for Web of Science ID 000179629200044

  View details for PubMedID 12471257

• Energy balance closure at FLUXNET sites 1st FLUXNET Synthesis Workshop Wilson, K., Goldstein, A., Falge, E., Aubinet, M., Baldocchi, D., Berbigier, P., Bernhofer, C., Ceulemans, R., Dolman, H., Field, C., Grelle, A., Ibrom, A., Law, B. E., Kowalski, A., Meyers, T., Moncrieff, J., Monson, R., Oechel, W., Tenhunen, J., Valentini, R., Verma, S. ELSEVIER SCIENCE BV. 2002: 223–43

  View details for Web of Science ID 000179188300012

• Carbon emissions from tropical deforestation and regrowth based on satellite observations for the 1980s and 1990s PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA DeFries, R. S., Houghton, R. A., Hansen, M. C., Field, C. B., Skole, D., Townshend, J. 2002; 99 (22): 14256-14261

  Abstract

  Carbon fluxes from tropical deforestation and regrowth are highly uncertain components of the contemporary carbon budget, due in part to the lack of spatially explicit and consistent information on changes in forest area. We estimate fluxes for the 1980s and 1990s using subpixel estimates of percent tree cover derived from coarse (National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer) satellite data in combination with a terrestrial carbon model. The satellite-derived estimates of change in forest area are lower than national reports and remote-sensing surveys from the United Nations Food and Agriculture Organization Forest Resource Assessment (FRA) in all tropical regions, especially for the 1980s. However, our results indicate that the net rate of tropical forest clearing increased approximately 10% from the 1980s to 1990s, most notably in southeast Asia, in contrast to an 11% reduction reported by the FRA. We estimate net mean annual carbon fluxes from tropical deforestation and regrowth to average 0.6 (0.3-0.8) and 0.9 (0.5-1.4) petagrams (Pg).yr(-1) for the 1980s and 1990s, respectively. Compared with previous estimates of 1.9 (0.6-2.5) Pg.yr(-1) based on FRA national statistics of changes in forest area, this alternative estimate suggests less "missing" carbon from the global carbon budget but increasing emissions from tropical land-use change.

  View details for DOI 10.1073/pnas.182560099

  View details for Web of Science ID 000178967400054

  View details for PubMedID 12384569

• Root production and demography in a california annual grassland under elevated atmospheric carbon dioxide GLOBAL CHANGE BIOLOGY Higgins, P. A., Jackson, R. B., Des Rosiers, J. M., Field, C. B. 2002; 8 (9): 841-850

  View details for Web of Science ID 000177545800003

• Satellite estimates of productivity and light use efficiency in United States agriculture, 1982-98 GLOBAL CHANGE BIOLOGY Lobell, D. B., Hicke, J. A., Asner, G. P., Field, C. B., Tucker, C. J., Los, S. O. 2002; 8 (8): 722-735

  View details for Web of Science ID 000176798400003

• Forest carbon sinks in the Northern Hemisphere ECOLOGICAL APPLICATIONS Goodale, C. L., Apps, M. J., Birdsey, R. A., Field, C. B., Heath, L. S., Houghton, R. A., Jenkins, J. C., Kohlmaier, G. H., Kurz, W., Liu, S. R., Nabuurs, G. J., Nilsson, S., Shvidenko, A. Z. 2002; 12 (3): 891-899

  View details for Web of Science ID 000175693800028

• Satellite-derived increases in net primary productivity across North America, 1982-1998 GEOPHYSICAL RESEARCH LETTERS Hicke, J. A., Asner, G. P., Randerson, J. T., Tucker, C., Los, S., Birdsey, R., Jenkins, J. C., Field, C., Holland, E. 2002; 29 (10)

  View details for DOI 10.1029/2001GL013578

  View details for Web of Science ID 000178888300079

• Trends in North American net primary productivity derived from satellite observations, 1982-1998 GLOBAL BIOGEOCHEMICAL CYCLES Hicke, J. A., Asner, G. P., Randerson, J. T., Tucker, C., Los, S., Birdsey, R., Jenkins, J. C., Field, C. 2002; 16 (2)

  View details for DOI 10.1029/2001GB001550

  View details for Web of Science ID 000178887900010

• Towards an ecological understanding of biological nitrogen fixation BIOGEOCHEMISTRY Vitousek, P. M., Cassman, K., Cleveland, C., Crews, T., Field, C. B., Grimm, N. B., Howarth, R. W., Marino, R., Martinelli, L., Rastetter, E. B., SPRENT, J. I. 2002; 57 (1): 1-45

  View details for Web of Science ID 000176001500002

• Artificial climate warming positively affects arbuscular mycorrhizae but decreases soil aggregate water stability in an annual grassland OIKOS Rillig, M. C., WRIGHT, S. F., Shaw, M. R., Field, C. B. 2002; 97 (1): 52-58

  View details for Web of Science ID 000176022200005

• Nitrogen controls on climate model evapotranspiration JOURNAL OF CLIMATE Dickinson, R. E., Berry, J. A., Bonan, G. B., Collatz, G. J., Field, C. B., Fung, I. Y., Goulden, M., Hoffmann, W. A., Jackson, R. B., Myneni, R., Sellers, P. J., Shaikh, M. 2002; 15 (3): 278-295

  View details for Web of Science ID 000173256600004

• Global change - Sharing the garden SCIENCE Field, C. B. 2001; 294 (5551): 2490-2491

  View details for Web of Science ID 000172927700038

  View details for PubMedID 11752562

• Recent patterns and mechanisms of carbon exchange by terrestrial ecosystems NATURE Schimel, D. S., House, J. I., Hibbard, K. A., Bousquet, P., Ciais, P., Peylin, P., Braswell, B. H., Apps, M. J., Baker, D., Bondeau, A., Canadell, J., Churkina, G., Cramer, W., Denning, A. S., Field, C. B., Friedlingstein, P., Goodale, C., Heimann, M., Houghton, R. A., Melillo, J. M., Moore, B., Murdiyarso, D., Noble, I., Pacala, S. W., Prentice, I. C., Raupach, M. R., Rayner, P. J., Scholes, R. J., Steffen, W. L., Wirth, C. 2001; 414 (6860): 169-172

  Abstract

  Knowledge of carbon exchange between the atmosphere, land and the oceans is important, given that the terrestrial and marine environments are currently absorbing about half of the carbon dioxide that is emitted by fossil-fuel combustion. This carbon uptake is therefore limiting the extent of atmospheric and climatic change, but its long-term nature remains uncertain. Here we provide an overview of the current state of knowledge of global and regional patterns of carbon exchange by terrestrial ecosystems. Atmospheric carbon dioxide and oxygen data confirm that the terrestrial biosphere was largely neutral with respect to net carbon exchange during the 1980s, but became a net carbon sink in the 1990s. This recent sink can be largely attributed to northern extratropical areas, and is roughly split between North America and Eurasia. Tropical land areas, however, were approximately in balance with respect to carbon exchange, implying a carbon sink that offset emissions due to tropical deforestation. The evolution of the terrestrial carbon sink is largely the result of changes in land use over time, such as regrowth on abandoned agricultural land and fire prevention, in addition to responses to environmental changes, such as longer growing seasons, and fertilization by carbon dioxide and nitrogen. Nevertheless, there remain considerable uncertainties as to the magnitude of the sink in different regions and the contribution of different processes.

  View details for Web of Science ID 000172029100037

  View details for PubMedID 11700548

• Assessing photosynthetic downregulation in sunflower stands with an optically-based model. Photosynthesis research Gamon, J. A., Field, C. B., Fredeen, A. L., Thayer, S. 2001; 67 (1-2): 113-25

  Abstract

  Using a simple light-use efficiency model based on optical measurements, we explored spatial patterns of photosynthetic activity in fertilized and unfertilized sunflower stands. The model had two components: (1) absorbed photosynthetically active radiation (APAR), and (2) radiation-use efficiency. APAR was the product of photosynthetic photon flux density (PPFD) and leaf absorptance, which was derived from leaf reflectance. Radiation-use efficiency was either assumed to be constant or allowed to vary linearly with the photochemical reflectance index (PRI), a measure of xanthophyll cycle pigment activity. When efficiency was assumed to be constant, the model overestimated photosynthetic rates in upper canopy layers exposed to direct PPFD, particularly in the unfertilized canopy due to the greater photosynthetic downregulation associated with higher levels of photoprotective (de-epoxidized) xanthophyll cycle pigments in these conditions. When efficiency was allowed to vary according to the PRI, modeled photosynthetic rates closely matched measured rates for all canopy layers in both treatments. These results illustrate the importance of considering reduced radiation-use efficiency due to photosynthetic downregulation when modeling photosynthesis from reflectance, and illustrate the potential for detecting radiation-use efficiency through leaf optical properties. At least under the conditions of this study, these results also suggest that xanthophyll cycle pigment activity and net carbon uptake are coordinately regulated, allowing assays of Photosystem II activity to reveal changing rates of net assimilation. Because the optical methods in this study are adaptable to multiple spatial scales (leaf to landscape), this approach may provide a scalable model for estimating photosynthetic rates independently from flux measurements.

  View details for DOI 10.1023/A:1010677605091

  View details for PubMedID 16228321

• Consistent land- and atmosphere-based US carbon sink estimates SCIENCE Pacala, S. W., Hurtt, G. C., Baker, D., Peylin, P., Houghton, R. A., Birdsey, R. A., Heath, L., Sundquist, E. T., Stallard, R. F., Ciais, P., Moorcroft, P., Caspersen, J. P., Shevliakova, E., Moore, B., Kohlmaier, G., Holland, E., Gloor, M., Harmon, M. E., Fan, S. M., SARMIENTO, J. L., Goodale, C. L., Schimel, D., Field, C. B. 2001; 292 (5525): 2316-2320

  Abstract

  For the period 1980-89, we estimate a carbon sink in the coterminous United States between 0.30 and 0.58 petagrams of carbon per year (petagrams of carbon = 10(15) grams of carbon). The net carbon flux from the atmosphere to the land was higher, 0.37 to 0.71 petagrams of carbon per year, because a net flux of 0.07 to 0.13 petagrams of carbon per year was exported by rivers and commerce and returned to the atmosphere elsewhere. These land-based estimates are larger than those from previous studies (0.08 to 0.35 petagrams of carbon per year) because of the inclusion of additional processes and revised estimates of some component fluxes. Although component estimates are uncertain, about one-half of the total is outside the forest sector. We also estimated the sink using atmospheric models and the atmospheric concentration of carbon dioxide (the tracer-transport inversion method). The range of results from the atmosphere-based inversions contains the land-based estimates. Atmosphere- and land-based estimates are thus consistent, within the large ranges of uncertainty for both methods. Atmosphere-based results for 1980-89 are similar to those for 1985-89 and 1990-94, indicating a relatively stable U.S. sink throughout the period.

  View details for Web of Science ID 000169455900054

  View details for PubMedID 11423659

• Resource optimization and symbiotic nitrogen fixation ECOSYSTEMS Rastetter, E. B., Vitousek, P. M., Field, C., Shaver, G. R., Herbert, D., AGREN, G. I. 2001; 4 (4): 369-388

  View details for Web of Science ID 000169413600010

• Contrasting effects of elevated CO2 on old and new soil carbon pools (vol 33, pg 365, 2001) SOIL BIOLOGY & BIOCHEMISTRY Cardon, Z. G., Hungate, B. A., Cambardella, C. A., Chapin, F. S., Field, C. B., Holland, E. A., Mooney, H. A. 2001; 33 (7-8): 1141-1141

  View details for Web of Science ID 000169257800030

• Species-specific responses of plant communities to altered carbon and nutrient availability GLOBAL CHANGE BIOLOGY Joel, G., Chapin, F. S., Chiariello, N. R., Thayer, S. S., Field, C. B. 2001; 7 (4): 435-450

  View details for Web of Science ID 000169084700008

• Biospheric primary production during an ENSO transition SCIENCE Behrenfeld, M. J., Randerson, J. T., McClain, C. R., Feldman, G. C., Los, S. O., Tucker, C. J., Falkowski, P. G., Field, C. B., Frouin, R., Esaias, W. E., Kolber, D. D., Pollack, N. H. 2001; 291 (5513): 2594-2597

  Abstract

  The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) provides global monthly measurements of both oceanic phytoplankton chlorophyll biomass and light harvesting by land plants. These measurements allowed the comparison of simultaneous ocean and land net primary production (NPP) responses to a major El Niño to La Niña transition. Between September 1997 and August 2000, biospheric NPP varied by 6 petagrams of carbon per year (from 111 to 117 petagrams of carbon per year). Increases in ocean NPP were pronounced in tropical regions where El Niño-Southern Oscillation (ENSO) impacts on upwelling and nutrient availability were greatest. Globally, land NPP did not exhibit a clear ENSO response, although regional changes were substantial.

  View details for Web of Science ID 000167861000039

  View details for PubMedID 11283369

• Contrasting effects of elevated CO2 on old and new soil carbon pools SOIL BIOLOGY & BIOCHEMISTRY Cardon, Z. G., Hungate, B. A., Cambardella, C. A., Chapin, F. S., Field, C. B., Holland, E. A., Mooney, H. A. 2001; 33 (3): 365-373

  View details for Web of Science ID 000167199100010

• Nitrogen limitation of microbial decomposition in a grassland under elevated CO2 NATURE Hu, S., Chapin, F. S., Firestone, M. K., Field, C. B., Chiariello, N. R. 2001; 409 (6817): 188-191

  Abstract

  Carbon accumulation in the terrestrial biosphere could partially offset the effects of anthropogenic CO2 emissions on atmospheric CO2. The net impact of increased CO2 on the carbon balance of terrestrial ecosystems is unclear, however, because elevated CO2 effects on carbon input to soils and plant use of water and nutrients often have contrasting effects on microbial processes. Here we show suppression of microbial decomposition in an annual grassland after continuous exposure to increased CO2 for five growing seasons. The increased CO2 enhanced plant nitrogen uptake, microbial biomass carbon, and available carbon for microbes. But it reduced available soil nitrogen, exacerbated nitrogen constraints on microbes, and reduced microbial respiration per unit biomass. These results indicate that increased CO2 can alter the interaction between plants and microbes in favour of plant utilization of nitrogen, thereby slowing microbial decomposition and increasing ecosystem carbon accumulation.

  View details for Web of Science ID 000166316200043

  View details for PubMedID 11196641

• Introduction. Photosynthesis research Berry, J. A., Field, C. B., Grossman, A. R. 2001; 67 (1-2): 1-3

  View details for PubMedID 16228311

• Common-pool resources and commons institutions - An overview of the applicability of the concept and approach to current environmental problems Symposium on Protecting the Commons - A Framework for Resource Management in the Americas Burger, J., Field, C., Norgaard, R. B., Ostrom, E., Policansky, D. ISLAND PRESS. 2001: 1–15

  View details for Web of Science ID 000168275600001

• Assessing photosynthetic downregulation in sunflower stands with an optically-based model PHOTOSYNTHESIS RESEARCH Gamon, J. A., Field, C. B., Fredeen, A. L., Thayer, S. 2001; 67 (1-2): 113-125

  View details for Web of Science ID 000169691500011

• Plant physiology of the "missing" carbon sink PLANT PHYSIOLOGY Field, C. B. 2001; 125 (1): 25-28

  View details for Web of Science ID 000167544600006

  View details for PubMedID 11154288

• Soil microbiota in two annual grasslands: responses to elevated atmospheric CO2 OECOLOGIA Hungate, B. A., Jaeger, C. H., Gamara, G., Chapin, F. S., Field, C. B. 2000; 124 (4): 589-598

  View details for Web of Science ID 000089509700013

• Belowground consequences of vegetation change and their treatment in models ECOLOGICAL APPLICATIONS Jackson, R. B., Schenk, H. J., Jobbagy, E. G., Canadell, J., Colello, G. D., Dickinson, R. E., Field, C. B., Friedlingstein, P., Heimann, M., Hibbard, K., Kicklighter, D. W., Kleidon, A., Neilson, R. P., Parton, W. J., Sala, O. E., Sykes, M. T. 2000; 10 (2): 470-483

  View details for Web of Science ID 000086008300013

• Carbon metabolism of the terrestrial biosphere: A multitechnique approach for improved understanding ECOSYSTEMS Canadell, J. G., Mooney, H. A., Baldocchi, D. D., Berry, J. A., Ehleringer, J. R., Field, C. B., Gower, S. T., Hollinger, D. Y., Hunt, J. E., Jackson, R. B., Running, S. W., Shaver, G. R., STEFFEN, W., Trumbore, S. E., Valentini, R., Bond, B. Y. 2000; 3 (2): 115-130

  View details for Web of Science ID 000087071600001

• Diverse mechanisms for CO2 effects on grassland litter decomposition GLOBAL CHANGE BIOLOGY Dukes, J. S., Field, C. B. 2000; 6 (2): 145-154

  View details for Web of Science ID 000086196300002

• Toward an allocation scheme for global terrestrial carbon models GLOBAL CHANGE BIOLOGY Friedlingstein, P., Joel, G., Field, C. B., Fung, I. Y. 1999; 5 (7): 755-770

  View details for Web of Science ID 000082646900002

• Increases in early season ecosystem uptake explain recent changes in the seasonal cycle of atmospheric CO2 at high northern latitudes GEOPHYSICAL RESEARCH LETTERS Randerson, J. T., Field, C. B., Fung, I. Y., Tans, P. P. 1999; 26 (17): 2765-2768

  View details for Web of Science ID 000082391100033

• Quantifying the response of photosynthesis to changes in leaf nitrogen content and leaf mass per area in plants grown under atmospheric CO2 enrichment PLANT CELL AND ENVIRONMENT Peterson, A. G., Ball, J. T., Luo, Y., Field, C. B., Curtis, P. S., Griffin, K. L., Gunderson, C. A., Norby, R. J., Tissue, D. T., Forstreuter, M., Rey, A., Vogel, C. S. 1999; 22 (9): 1109-1119

  View details for Web of Science ID 000082536700006

• Combining satellite data and biogeochemical models to estimate global effects of human-induced land cover change on carbon emissions and primary productivity GLOBAL BIOGEOCHEMICAL CYCLES DeFries, R. S., Field, C. B., Fung, I., Collatz, G. J., Bounoua, L. 1999; 13 (3): 803-815

  View details for Web of Science ID 000082365000011

• Ecosystem constraints to symbiotic nitrogen fixers: a simple model and its implications BIOGEOCHEMISTRY Vitousek, P. M., Field, C. B. 1999; 46 (1-3): 179-202

  View details for Web of Science ID 000080776300010

• Linking C-13-based estimates of land and ocean sinks with predictions of carbon storage from CO2 fertilization of plant growth TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY Randerson, J. T., Thompson, M. V., Field, C. B. 1999; 51 (3): 668-678

  View details for Web of Science ID 000081661700007

• Fungal root colonization responses in natural grasslands after long-term exposure to elevated atmospheric CO2 GLOBAL CHANGE BIOLOGY Rillig, M. C., Field, C. B., Allen, M. F. 1999; 5 (5): 577-585

  View details for Web of Science ID 000080634800007

• Soil biota responses to long-term atmospheric CO2 enrichment in two California annual grasslands OECOLOGIA Rillig, M. C., Field, C. B., Allen, M. F. 1999; 119 (4): 572-577

  Abstract

  Root, arbuscular-mycorrhizal (AM), soil faunal (protozoa and microarthropods), and microbial responses to field exposure to CO2 for six growing seasons were measured in spring 1997 in two adjacent grassland communities. The grasslands showed contrasting root responses to CO2 enrichment: whereas root length was not affected in the sandstone grassland, it was greater in the serpentine grassland, as was specific root length. AM fungal hyphal lengths were greater in the sandstone, but were unaffected in the serpentine community. This lent support to the hypothesis that there may be a tradeoff in resource allocation to more fine roots or greater mycorrhizal extraradical hyphal length. AM root infection was greater in both communities at elevated CO2, as was the proportion of roots containing arbuscules. Our data on total hyphal lengths, culturable and active fungi, bacteria, and protozoa supported the hypothesis that the fungal food chain was more strongly stimulated than the bacterial chain. This study is one of the first to test these hypotheses in natural multi-species communities in the field.

  View details for Web of Science ID 000081128300013

• Revisiting the commons: local lessons, global challenges. Science Ostrom, E., Burger, J., Field, C. B., Norgaard, R. B., Policansky, D. 1999; 284 (5412): 278-282

  Abstract

  In a seminal paper, Garrett Hardin argued in 1968 that users of a commons are caught in an inevitable process that leads to the destruction of the resources on which they depend. This article discusses new insights about such problems and the conditions most likely to favor sustainable uses of common-pool resources. Some of the most difficult challenges concern the management of large-scale resources that depend on international cooperation, such as fresh water in international basins or large marine ecosystems. Institutional diversity may be as important as biological diversity for our long-term survival.

  View details for PubMedID 10195886

• Sustainability - Revisiting the commons: Local lessons, global challenges SCIENCE Ostrom, E., Burger, J., Field, C. B., Norgaard, R. B., Policansky, D. 1999; 284 (5412): 278-282

  View details for Web of Science ID 000079636400032

• The effects of chamber pressurization on soil-surface CO2 flux and the implications for NEE measurements under elevated CO2 GLOBAL CHANGE BIOLOGY Lund, C. P., Riley, W. J., Pierce, L. L., Field, C. B. 1999; 5 (3): 269-281

  View details for Web of Science ID 000079231000003

• The photosynthesis leaf nitrogen relationship at ambient and elevated atmospheric carbon dioxide: a meta-analysis GLOBAL CHANGE BIOLOGY Peterson, A. G., Ball, J. T., Luo, Y. Q., Field, C. B., Reich, P. B., Curtis, P. S., Griffin, K. L., Gunderson, C. A., Norby, R. J., Tissue, D. T., Forstreuter, M., Rey, A., Vogel, C. S. 1999; 5 (3): 331-346

  View details for Web of Science ID 000079231000007

• Interactions between vegetation and climate: Radiative and physiological effects of doubled atmospheric CO2 JOURNAL OF CLIMATE Bounoua, L., Collatz, G. J., Sellers, P. J., Randall, D. A., Dazlich, D. A., Los, S. O., Berry, J. A., Fung, I., Tucker, C. J., Field, C. B., Jensen, T. G. 1999; 12 (2): 309-324

  View details for Web of Science ID 000079037700001

• Influence of fertilization and atmospheric CO2 enrichment on ecosystem CO2 and H2O exchanges in single- and multiple-species grassland microcosms ENVIRONMENTAL AND EXPERIMENTAL BOTANY Fredeen, A. L., Koch, G. W., Field, C. B. 1998; 40 (2): 147-157

  View details for Web of Science ID 000076239500006

• Primary production of the biosphere: Integrating terrestrial and oceanic components SCIENCE Field, C. B., Behrenfeld, M. J., Randerson, J. T., Falkowski, P. 1998; 281 (5374): 237-240

  View details for Web of Science ID 000074714200042

• Primary production of the biosphere: integrating terrestrial and oceanic components Science (New York, N.Y.) Field, C. B., Behrenfeld, M. J., Randerson, J. T., Falkowski, P. 1998; 281 (5374): 237-40

  Abstract

  Integrating conceptually similar models of the growth of marine and terrestrial primary producers yielded an estimated global net primary production (NPP) of 104.9 petagrams of carbon per year, with roughly equal contributions from land and oceans. Approaches based on satellite indices of absorbed solar radiation indicate marked heterogeneity in NPP for both land and oceans, reflecting the influence of physical and ecological processes. The spatial and temporal distributions of ocean NPP are consistent with primary limitation by light, nutrients, and temperature. On land, water limitation imposes additional constraints. On land and ocean, progressive changes in NPP can result in altered carbon storage, although contrasts in mechanisms of carbon storage and rates of organic matter turnover result in a range of relations between carbon storage and changes in NPP.

  View details for PubMedID 9657713

• The terrestrial carbon cycle: Implications for the Kyoto Protocol SCIENCE STEFFEN, W., Noble, I., Canadell, J., Apps, M., Schulze, E. D., Jarvis, P. G., Baldocchi, D., Ciais, P., Cramer, W., Ehleringer, J., Farquhar, G., Field, C. B., Ghazi, A., Gifford, R., Heimann, M., Houghton, R., Kabat, P., Korner, C., Lambin, E., Linder, S., Mooney, H. A., Murdiyarso, D., Post, W. M., Prentice, I. C., Raupach, M. R., Schimel, D. S., Shvidenko, A., Valentini, R. 1998; 280 (5368): 1393-1394

  View details for Web of Science ID 000073883400038

• Arbuscular mycorrhizal percent root infection and infection intensity of Bromus hordeaceus grown in elevated atmospheric CO2 MYCOLOGIA Rillig, M. C., Allen, M. F., Klironomos, J. N., Field, C. B. 1998; 90 (2): 199-205

  View details for Web of Science ID 000072993100005

• Mangrove biodiversity and ecosystem function International Workshop on Biodiversity and Ecosystem Function in Marine Ecosystems Field, C. B., Osborn, J. G., Hoffmann, L. L., Polsenberg, J. F., Ackerly, D. D., Berry, J. A., Bjorkman, O., Held, Z., Matson, P. A., Mooney, H. A. WILEY-BLACKWELL PUBLISHING, INC. 1998: 3–14

  View details for Web of Science ID 000074252300002

• and nutrients. Oecologia Rillig, M. C., Allen, M. F., Klironomos, J. N., Chiariello, N. R., Field, C. B. 1998; 113 (2): 252-259

  Abstract

  Five co-occurring plant species from an annual mediterranean grassland were grown in monoculture for 4 months in pots inside open-top chambers at the Jasper Ridge Biological Preserve (San Mateo County, California). The plants were exposed to elevated atmospheric CO2 and soil nutrient enrichment in a complete factorial experiment. The response of root-inhabiting non-mycorrhizal and arbuscular mycorrhizal fungi to the altered resource base depended strongly on the plant species. Elevated CO2 and fertilization altered the ratio of non-mycorrhizal to mycorrhizal fungal colonization for some plant species, but not for others. Percent root infection by non-mycorrhizal fungi increased by over 500% for Linanthus parviflorus in elevated CO2, but decreased by over 80% for Bromus hordeaceus. By contrast, the mean percent infection by mycorrhizal fungi increased in response to elevated CO2 for all species, but significantly only for Avena barbata and B. hordeaceus. Percent infection by mycorrhizal fungi increased, decreased, or remained unchanged for different plant hosts in response to fertilization. There was evidence of a strong interaction between the two treatments for some plant species and non-mycorrhizal and mycorrhizal fungi. This study demonstrated plant species- and soil fertility-dependent shifts in below-ground plant resource allocation to different morpho-groups of fungal symbionts. This may have consequences for plant community responses to elevated CO2 in this California grassland ecosystem.

  View details for DOI 10.1007/s004420050376

  View details for PubMedID 28308205

• Plant species-specific changes in root-inhabiting fungi in a California annual grassland: responses to elevated CO2 and nutrients OECOLOGIA Rillig, M. C., Allen, M. F., Klironomos, J. N., Chiariello, N. R., Field, C. B. 1998; 113 (2): 252-259

  Abstract

  Five co-occurring plant species from an annual mediterranean grassland were grown in monoculture for 4 months in pots inside open-top chambers at the Jasper Ridge Biological Preserve (San Mateo County, California). The plants were exposed to elevated atmospheric CO2 and soil nutrient enrichment in a complete factorial experiment. The response of root-inhabiting non-mycorrhizal and arbuscular mycorrhizal fungi to the altered resource base depended strongly on the plant species. Elevated CO2 and fertilization altered the ratio of non-mycorrhizal to mycorrhizal fungal colonization for some plant species, but not for others. Percent root infection by non-mycorrhizal fungi increased by over 500% for Linanthus parviflorus in elevated CO2, but decreased by over 80% for Bromus hordeaceus. By contrast, the mean percent infection by mycorrhizal fungi increased in response to elevated CO2 for all species, but significantly only for Avena barbata and B. hordeaceus. Percent infection by mycorrhizal fungi increased, decreased, or remained unchanged for different plant hosts in response to fertilization. There was evidence of a strong interaction between the two treatments for some plant species and non-mycorrhizal and mycorrhizal fungi. This study demonstrated plant species- and soil fertility-dependent shifts in below-ground plant resource allocation to different morpho-groups of fungal symbionts. This may have consequences for plant community responses to elevated CO2 in this California grassland ecosystem.

  View details for Web of Science ID 000071658500014

• Carbon 13 exchanges between the atmosphere and biosphere GLOBAL BIOGEOCHEMICAL CYCLES Fung, I., Field, C. B., Berry, J. A., Thompson, M. V., Randerson, J. T., Malmstrom, C. M., Vitousek, P. M., Collatz, G. J., Sellers, P. J., Randall, D. A., Denning, A. S., Badeck, F., John, J. 1997; 11 (4): 507-533

  View details for Web of Science ID A1997YK11800004

• Disproportional increases in photosynthesis and plant biomass in a Californian grassland exposed to elevated CO2: a simulation analysis FUNCTIONAL ECOLOGY Luo, Y., Chen, J. L., Reynolds, J. F., Field, C. B., Mooney, H. A. 1997; 11 (6): 696-704

  View details for Web of Science ID 000071560300004

• The contribution of terrestrial sources and sinks to trends in the seasonal cycle of atmospheric carbon dioxide GLOBAL BIOGEOCHEMICAL CYCLES Randerson, J. T., Thompson, M. V., Conway, T. J., Fung, I. Y., Field, C. B. 1997; 11 (4): 535-560

  View details for Web of Science ID A1997YK11800005

• Production efficiency in sunflower: The role of water and nitrogen stress REMOTE SENSING OF ENVIRONMENT Joel, G., Gamon, J. A., Field, C. B. 1997; 62 (2): 176-188

  View details for Web of Science ID A1997YB44100005

• Elevated atmospheric CO2 increases water availability in a water-limited grassland ecosystem JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION Fredeen, A. L., Randerson, J. T., Holbrook, N. M., Field, C. B. 1997; 33 (5): 1033-1039

  View details for Web of Science ID A1997YF95900009

• Assessing photosynthetic radiation-use efficiency of emergent aquatic vegetation from spectral reflectance AQUATIC BOTANY Penuelas, J., Filella, I., Gamon, J. A., Field, C. 1997; 58 (3-4): 307-315

  View details for Web of Science ID A1997YL24600008

• Interannual variation in global-scale net primary production: Testing model estimates GLOBAL BIOGEOCHEMICAL CYCLES Malmstrom, C. M., Thompson, M. V., Juday, G. P., Los, S. O., Randerson, J. T., Field, C. B. 1997; 11 (3): 367-392

  View details for Web of Science ID A1997XT61900006

• The fate of carbon in grasslands under carbon dioxide enrichment NATURE Hungate, B. A., Holland, E. A., Jackson, R. B., Chapin, F. S., Mooney, H. A., Field, C. B. 1997; 388 (6642): 576-579

  View details for Web of Science ID A1997XP72200047

• CO2 effects on the water budget of grassland microcosm communities GLOBAL CHANGE BIOLOGY Field, C. B., Lund, C. P., Chiariello, N. R., Mortimer, B. E. 1997; 3 (3): 197-206

  View details for Web of Science ID A1997XF04800004

• Decomposition of litter produced under elevated CO2: Dependence on plant species and nutrient supply BIOGEOCHEMISTRY Franck, V. M., Hungate, B. A., Chapin, F. S., Field, C. B. 1997; 36 (3): 223-237

  View details for Web of Science ID A1997WK05600001

• Virus-induced differences in the response of oat plants to elevated carbon dioxide PLANT CELL AND ENVIRONMENT Malmstrom, C. M., Field, C. B. 1997; 20 (2): 178-188

  View details for Web of Science ID A1997WJ46400004

• Modeling the Exchanges of Energy, Water, and Carbon Between Continents and the Atmosphere Science (New York, N.Y.) Sellers, P. J., Dickinson, R. E., Randall, D. A., Betts, A. K., Hall, F. G., Berry, J. A., Collatz, G. J., Denning, A. S., Mooney, H. A., Nobre, C. A., Sato, N., Field, C. B., Henderson-Sellers, A. 1997; 275 (5299): 502-9

  Abstract

  Atmospheric general circulation models used for climate simulation and weather forecasting require the fluxes of radiation, heat, water vapor, and momentum across the land-atmosphere interface to be specified. These fluxes are calculated by submodels called land surface parameterizations. Over the last 20 years, these parameterizations have evolved from simple, unrealistic schemes into credible representations of the global soil-vegetation-atmosphere transfer system as advances in plant physiological and hydrological research, advances in satellite data interpretation, and the results of large-scale field experiments have been exploited. Some modern schemes incorporate biogeochemical and ecological knowledge and, when coupled with advanced climate and ocean models, will be capable of modeling the biological and physical responses of the Earth system to global change, for example, increasing atmospheric carbon dioxide.

  View details for PubMedID 8999789

• Modeling the exchanges of energy, water, and carbon between continents and the atmosphere SCIENCE Sellers, P. J., Dickinson, R. E., Randall, D. A., Betts, A. K., Hall, F. G., Berry, J. A., Collatz, G. J., Denning, A. S., Mooney, H. A., Nobre, C. A., Sato, N., Field, C. B., Henderson-Sellers, A. 1997; 275 (5299): 502-509

  View details for Web of Science ID A1997WE25700036

• Adapting GePSi (generic plant simulator) for modeling studies in the Jasper Ridge CO2 project ECOLOGICAL MODELLING Luo, Y., Field, C. B., Mooney, H. A. 1997; 94 (1): 81-88

  View details for Web of Science ID A1997WM97900008

• Stimulation of grassland nitrogen cycling under carbon dioxide enrichment OECOLOGIA Hungate, B. A., Chapin, F. S., Zhong, H., Holland, E. A., Field, C. B. 1997; 109 (1): 149-153

  View details for Web of Science ID A1997WH54700019

• Substrate limitations for heterotrophs: Implications for models that estimate the seasonal cycle of atmospheric CO2 GLOBAL BIOGEOCHEMICAL CYCLES Randerson, J. T., Thompson, M. V., Malmstrom, C. M., Field, C. B., Fung, I. Y. 1996; 10 (4): 585-602

  View details for Web of Science ID A1996VV17500003

• Change in net primary production and heterotrophic respiration: How much is necessary to sustain the terrestrial carbon sink? 1st Science Conference of the Global Analysis, Interpretation and Modelling Task Force Thompson, M. V., Randerson, J. T., Malmstrom, C. M., Field, C. B. AMER GEOPHYSICAL UNION. 1996: 711–26

  View details for Web of Science ID A1996VV17500012

• Elevated CO2 increases belowground respiration in California grasslands OECOLOGIA Luo, Y. Q., Jackson, R. B., Field, C. B., Mooney, H. A. 1996; 108 (1): 130-137

  Abstract

  This study was designed to identify potential effects of elevated CO2 on belowground respiration (the sum of root and heterotrophic respiration) in field and microcosm ecosystems and on the annual carbon budget. We made three sets of respiration measurements in two CO2 treatments, i.e., (1) monthly in the sandstone grassland and in microcosms from November 1993 to June 1994; (2) at the annual peak of live biomass (March and April) in the serpentine and sandstone grasslands in 1993 and 1994; and (3) at peak biomass in the microcosms with monocultures of seven species in 1993. To help understand ecosystem carbon cycling, we also made supplementary measurements of belowground respiration monthly in sandstone and serpentine grasslands located within 500 m of the CO2 experiment site. The seasonal average respiration rate in the sandstone grassland was 2.12 μmol m(-2) s(-1) in elevated CO2, which was 42% higher than the 1.49 μmol m(-2) s(-1) measured in ambient CO2 (P=0.007). Studies of seven individual species in the microcosms indicated that respiration was positively correlated with plant biomass and increased, on average, by 70% with CO2. Monthly measurements revealed a strong seasonality in belowground respiration, being low (0-0.5 μmol CO2 m(-2) s(-1) in the two grasslands adjacent to the CO2 site) in the summer dry season and high (2-4 μmol CO2 m(-2) s(-1) in the sandstone grassland and 2-7 μmol CO2 m(-2) s(-1) in the microcosms) during the growing season from the onset of fall rains in November to early spring in April and May. Estimated annual carbon effluxes from the soil were 323 and 440 g C m(-2) year(-1) for the sandstone grasslands in ambient and elevated CO2. That CO2-stimulated increase in annual soil carbon efflux is more than twice as big as the increase in aboveground net primary productivity (NPPa) and approximately 60% of NPPa in this grassland in the current CO2 environment. The results of this study suggest that below-ground respiration can dissipate most of the increase in photosynthesis stimulated by elevated CO2.

  View details for Web of Science ID A1996VL38300017

• increases belowground respiration in California grasslands. Oecologia Luo, Y., Jackson, R. B., Field, C. B., Mooney, H. A. 1996; 108 (1): 130-137

  Abstract

  This study was designed to identify potential effects of elevated CO2 on belowground respiration (the sum of root and heterotrophic respiration) in field and microcosm ecosystems and on the annual carbon budget. We made three sets of respiration measurements in two CO2 treatments, i.e., (1) monthly in the sandstone grassland and in microcosms from November 1993 to June 1994; (2) at the annual peak of live biomass (March and April) in the serpentine and sandstone grasslands in 1993 and 1994; and (3) at peak biomass in the microcosms with monocultures of seven species in 1993. To help understand ecosystem carbon cycling, we also made supplementary measurements of belowground respiration monthly in sandstone and serpentine grasslands located within 500 m of the CO2 experiment site. The seasonal average respiration rate in the sandstone grassland was 2.12 μmol m(-2) s(-1) in elevated CO2, which was 42% higher than the 1.49 μmol m(-2) s(-1) measured in ambient CO2 (P=0.007). Studies of seven individual species in the microcosms indicated that respiration was positively correlated with plant biomass and increased, on average, by 70% with CO2. Monthly measurements revealed a strong seasonality in belowground respiration, being low (0-0.5 μmol CO2 m(-2) s(-1) in the two grasslands adjacent to the CO2 site) in the summer dry season and high (2-4 μmol CO2 m(-2) s(-1) in the sandstone grassland and 2-7 μmol CO2 m(-2) s(-1) in the microcosms) during the growing season from the onset of fall rains in November to early spring in April and May. Estimated annual carbon effluxes from the soil were 323 and 440 g C m(-2) year(-1) for the sandstone grasslands in ambient and elevated CO2. That CO2-stimulated increase in annual soil carbon efflux is more than twice as big as the increase in aboveground net primary productivity (NPPa) and approximately 60% of NPPa in this grassland in the current CO2 environment. The results of this study suggest that below-ground respiration can dissipate most of the increase in photosynthesis stimulated by elevated CO2.

  View details for DOI 10.1007/BF00333224

  View details for PubMedID 28307743

• Effects of CO2 and nutrient enrichment on tissue quality of two California annuals OECOLOGIA Chu, C. C., Field, C. B., Mooney, H. A. 1996; 107 (4): 433-440

  Abstract

  The effects of CO2 enrichment and soil nutrient status on tissue quality were investigated and related to the potential effect on growth and decomposition. Two California annuals, Avena fatua and Plantago erecta, were grown at ambient and ambient plus 35 Pa atmospheric CO2 in nutrient unamended and amended serpentine soil. Elevated CO2 led to significantly increased Avena shoot nitrogen concentrations in the nutrient amended treatment. It also led to decreased lignin concentrations in Avena roots in both nutrient treatments, and in Plantago shoots and roots with nutrient addition. Concentrations of total nonstructural carbohydrate (TNC) and carbon did not change with elevated CO2 in either species. As a consequence of increased biomass accumulation, increased CO2 led to larger total pools of TNC, lignin, total carbon, and total nitrogen in Avena with nutrient additions. Doubling CO2 had no significant effect on Plantago. Given the limited changes in the compounds related to decomposibility and plant growth, effects of increased atmospheric CO2 mediated through tissue composition on Avena and Plantago are likely to be minor and depend on site fertility. This study suggests that other factors such as litter moisture, whether or not litter is on the ground, and biomass allocation among roots and shoots, are likely to be more important in this California grassland ecosystem. CO2 could influence those directly as well as indirectly.

  View details for Web of Science ID A1996VH67200003

• and nutrient enrichment on tissue quality of two California annuals. Oecologia Chu, C. C., Field, C. B., Mooney, H. A. 1996; 107 (4): 433-440

  Abstract

  The effects of CO2 enrichment and soil nutrient status on tissue quality were investigated and related to the potential effect on growth and decomposition. Two California annuals, Avena fatua and Plantago erecta, were grown at ambient and ambient plus 35 Pa atmospheric CO2 in nutrient unamended and amended serpentine soil. Elevated CO2 led to significantly increased Avena shoot nitrogen concentrations in the nutrient amended treatment. It also led to decreased lignin concentrations in Avena roots in both nutrient treatments, and in Plantago shoots and roots with nutrient addition. Concentrations of total nonstructural carbohydrate (TNC) and carbon did not change with elevated CO2 in either species. As a consequence of increased biomass accumulation, increased CO2 led to larger total pools of TNC, lignin, total carbon, and total nitrogen in Avena with nutrient additions. Doubling CO2 had no significant effect on Plantago. Given the limited changes in the compounds related to decomposibility and plant growth, effects of increased atmospheric CO2 mediated through tissue composition on Avena and Plantago are likely to be minor and depend on site fertility. This study suggests that other factors such as litter moisture, whether or not litter is on the ground, and biomass allocation among roots and shoots, are likely to be more important in this California grassland ecosystem. CO2 could influence those directly as well as indirectly.

  View details for DOI 10.1007/BF00333932

  View details for PubMedID 28307384

• VEMAP: Model shootout at the sub-continental corral TRENDS IN ECOLOGY & EVOLUTION Field, C. B., Ruimy, A., Luo, Y. Q., Malmstrom, C. M., Randerson, J. T., Thompson, M. V. 1996; 11 (8): 313-314

  View details for Web of Science ID A1996UX90900002

  View details for PubMedID 21237858

• The use of CO2 flux measurements in models of the global terrestrial carbon budget GLOBAL CHANGE BIOLOGY Ruimy, A., Kergoat, L., Field, C. B., Saugier, B. 1996; 2 (3): 287-296

  View details for Web of Science ID A1996UT34400012

• A revised land surface parameterization (SiB2) for atmospheric GCMs .1. Model formulation JOURNAL OF CLIMATE Sellers, P. J., Randall, D. A., Collatz, G. J., Berry, J. A., Field, C. B., Dazlich, D. A., Zhang, C., Collelo, G. D., Bounoua, L. 1996; 9 (4): 676-705

  View details for Web of Science ID A1996UJ64300002

• Comparison of radiative and physiological effects of doubled atmospheric CO2 on climate SCIENCE Sellers, P. J., Bounoua, L., Collatz, G. J., Randall, D. A., Dazlich, D. A., Los, S. O., Berry, J. A., Fung, I., Tucker, C. J., Field, C. B., Jensen, T. G. 1996; 271 (5254): 1402-1406

  View details for Web of Science ID A1996TY96100042

• Detecting changes in soil carbon in CO2 enrichment experiments International GCTE Workshop on Plant-Soil Carbon Below Ground: The Effects of Elevated Carbon Dioxide Hungate, B. A., Jackson, R. B., Field, C. B., Chapin, F. S. SPRINGER. 1996: 135–45

  View details for Web of Science ID A1996WZ00700004

• NEGATIVE XYLEM PRESSURES IN PLANTS - A TEST OF THE BALANCING PRESSURE TECHNIQUE SCIENCE Holbrook, N. M., Burns, M. J., Field, C. B. 1995; 270 (5239): 1193-1194

  View details for Web of Science ID A1995TE90500054

• MAPPING THE LAND-SURFACE FOR GLOBAL ATMOSPHERE-BIOSPHERE MODELS - TOWARD CONTINUOUS DISTRIBUTIONS OF VEGETATIONS FUNCTIONAL-PROPERTIES JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES DeFries, R. S., Field, C. B., Fung, I., Justice, C. O., Los, S., Matson, P. A., Matthews, E., Mooney, H. A., Potter, C. S., Prentice, K., Sellers, P. J., Townshend, J. R., Tucker, C. J., Ustin, S. L., Vitousek, P. M. 1995; 100 (D10): 20867-20882

  View details for Web of Science ID A1995TD50700007

• STOMATAL RESPONSES TO INCREASED CO2 - IMPLICATIONS FROM THE PLANT TO THE GLOBAL-SCALE PLANT CELL AND ENVIRONMENT Field, C. B., Jackson, R. B., Mooney, H. A. 1995; 18 (10): 1214-1225

  View details for Web of Science ID A1995TA94000011

• ECOSYSTEM GAS-EXCHANGE IN A CALIFORNIA GRASSLAND - SEASONAL PATTERNS AND IMPLICATIONS FOR SCALING ECOLOGY Valentini, R., Gamon, J. A., Field, C. B. 1995; 76 (6): 1940-1952

  View details for Web of Science ID A1995RQ24800023

• Effects of atmospheric CO2 enrichment on ecosystem CO2 exchange in a nutrient and water limited grassland 1st Global Change and Terrestrial Ecosystems Science Conference Fredeen, A. L., Koch, G. W., Field, C. B. WILEY-BLACKWELL PUBLISHING, INC. 1995: 215–19

  View details for Web of Science ID A1995TR05500007

• CONTRASTING LEAF AND ECOSYSTEM CO2 AND H2O EXCHANGE IN AVENA-FATUA MONOCULTURE - GROWTH AT AMBIENT AND ELEVATED CO2 PHOTOSYNTHESIS RESEARCH Fredeen, A. L., Field, C. B. 1995; 43 (3): 263-271

  View details for Web of Science ID A1995RH51300009

• Photosynthesis, growth and density for the dominant species in a CO2-enriched grassland 1st Global Change and Terrestrial Ecosystems Science Conference Jackson, R. B., Luo, Y., Cardon, Z. G., Sala, O. E., Field, C. B., Mooney, H. A. WILEY-BLACKWELL PUBLISHING, INC. 1995: 221–25

  View details for Web of Science ID A1995TR05500008

• RELATIONSHIPS BETWEEN NDVI, CANOPY STRUCTURE, AND PHOTOSYNTHESIS IN 3 CALIFORNIAN VEGETATION TYPES ECOLOGICAL APPLICATIONS Gamon, J. A., Field, C. B., Goulden, M. L., Griffin, K. L., Hartley, A. E., Joel, G., Penuelas, J., Valentini, R. 1995; 5 (1): 28-41

  View details for Web of Science ID A1995QK27600007

• GLOBAL NET PRIMARY PRODUCTION - COMBINING ECOLOGY AND REMOTE-SENSING ISLSCP (International Satellite Land Surface Climatology Project) Workshop Field, C. B., Randerson, J. T., Malmstrom, C. M. ELSEVIER SCIENCE INC. 1995: 74–88

  View details for Web of Science ID A1995QF36200007

• REMOTE-SENSING OF THE LAND-SURFACE FOR STUDIES OF GLOBAL CHANGE - MODELS, ALGORITHMS, EXPERIMENTS REMOTE SENSING OF ENVIRONMENT Sellers, P. J., Meeson, B. W., Hall, F. G., Asrar, G., Murphy, R. E., Schiffer, R. A., BRETHERTON, F. P., Dickinson, R. E., Ellingson, R. G., Field, C. B., Huemmrich, K. F., Justice, C. O., Melack, J. M., Roulet, N. T., Schimel, D. S., TRY, P. D. 1995; 51 (1): 3-26

  View details for Web of Science ID A1995QF36200002

• PREDICTING RESPONSES OF PHOTOSYNTHESIS AND ROOT FRACTION TO ELEVATED [CO2](A) - INTERACTIONS AMONG CARBON, NITROGEN, AND GROWTH PLANT CELL AND ENVIRONMENT Luo, Y., Field, C. B., Mooney, H. A. 1994; 17 (11): 1195-1204

  View details for Web of Science ID A1994PP94800003

• CO2 ALTERS WATER-USE, CARBON GAIN, AND YIELD FOR THE DOMINANT SPECIES IN A NATURAL GRASSLAND OECOLOGIA Jackson, R. B., Sala, O. E., Field, C. B., Mooney, H. A. 1994; 98 (3-4): 257-262

  View details for Web of Science ID A1994PE43200003

• CO2 alters water use, carbon gain, and yield for the dominant species in a natural grassland. Oecologia Jackson, R. B., Sala, O. E., Field, C. B., Mooney, H. A. 1994; 98 (3-4): 257-262

  Abstract

  Global atmospheric CO2 is increasing at a rate of 1.5-2 ppm per year and is predicted to double by the end of the next century. Understanding how terrestrial ecosystems will respond in this changing environment is an important goal of current research. Here we present results from a field study of elevated CO2 in a California annual grassland. Elevated CO2 led to lower leaf-level stomatal conductance and transpiration (approximately 50%) and higher mid-day leaf water potentials (30-35%) in the most abundant species of the grassland, Avena barbata Brot. Higher CO2 concentrations also resulted in greater midday photosynthetic rates (70% on average). The effects of CO2 on stomatal conductance and leaf water potential decreased towards the end of the growing season, when Avena began to show signs of senescence. Water-use efficiency was approximately doubled in elevated CO2, as estimated by instantaneous gas-exchange measurements and seasonal carbon isotope discrimination. Increases in CO2 and photosynthesis resulted in more seeds per plant (30%) and taller and heavier plants (27% and 41%, respectively). Elevated CO2 also reduced seed N concentrations (9%).

  View details for DOI 10.1007/BF00324212

  View details for PubMedID 28313900

• REFLECTANCE INDEXES ASSOCIATED WITH PHYSIOLOGICAL-CHANGES IN NITROGEN-LIMITED AND WATER-LIMITED SUNFLOWER LEAVES REMOTE SENSING OF ENVIRONMENT Penuelas, J., Gamon, J. A., Fredeen, A. L., Merino, J., Field, C. B. 1994; 48 (2): 135-146

  View details for Web of Science ID A1994NN40900003

• 3 METHODS FOR MONITORING THE GAS-EXCHANGE OF INDIVIDUAL TREE CANOPIES - VENTILATED-CHAMBER, SAP-FLOW AND PENMAN-MONTEITH MEASUREMENTS ON EVERGREEN OAKS FUNCTIONAL ECOLOGY Goulden, M. L., Field, C. B. 1994; 8 (1): 125-135

  View details for Web of Science ID A1994MW76100017

• TERRESTRIAL ECOSYSTEM PRODUCTION - A PROCESS MODEL-BASED ON GLOBAL SATELLITE AND SURFACE DATA GLOBAL BIOGEOCHEMICAL CYCLES Potter, C. S., Randerson, J. T., Field, C. B., Matson, P. A., Vitousek, P. M., Mooney, H. A., Klooster, S. A. 1993; 7 (4): 811-841

  View details for Web of Science ID A1993MM23400006

• ASSESSING COMMUNITY TYPE, PLANT BIOMASS, PIGMENT COMPOSITION, AND PHOTOSYNTHETIC EFFICIENCY OF AQUATIC VEGETATION FROM SPECTRAL REFLECTANCE REMOTE SENSING OF ENVIRONMENT Penuelas, J., Gamon, J. A., Griffin, K. L., Field, C. B. 1993; 46 (2): 110-118

  View details for Web of Science ID A1993MD66500001

• PATTERNS OF STEM PHOTOSYNTHESIS IN 2 INVASIVE LEGUMES (SPARTIUM-JUNCEUM, CYTISUS-SCOPARIUS) OF THE CALIFORNIA COASTAL REGION AMERICAN JOURNAL OF BOTANY Nilsen, E. T., KARPA, D., Mooney, H. A., Field, C. 1993; 80 (10): 1126-1136

  View details for Web of Science ID A1993MD09200004

• FUNCTIONAL PATTERNS IN AN ANNUAL GRASSLAND DURING AN AVIRIS OVERFLIGHT REMOTE SENSING OF ENVIRONMENT Gamon, J. A., Field, C. B., Roberts, D. A., Ustin, S. L., Valentini, R. 1993; 44 (2-3): 239-253

  View details for Web of Science ID A1993LB11800009

• ENVIRONMENTAL-EFFECTS OF CIRCADIAN-RHYTHMS IN PHOTOSYNTHESIS AND STOMATAL OPENING PLANTA HENNESSEY, T. L., FREEDEN, A. L., Field, C. B. 1993; 189 (3): 369-376

  View details for Web of Science ID A1993KP26100009

• CANOPY REFLECTANCE, PHOTOSYNTHESIS, AND TRANSPIRATION .3. A REANALYSIS USING IMPROVED LEAF MODELS AND A NEW CANOPY INTEGRATION SCHEME REMOTE SENSING OF ENVIRONMENT Sellers, P. J., Berry, J. A., Collatz, G. J., Field, C. B., Hall, F. G. 1992; 42 (3): 187-216

  View details for Web of Science ID A1992KF59200003

• AMMONIUM AND NITRATE UPTAKE IN GAP, GENERALIST AND UNDERSTORY SPECIES OF THE GENUS PIPER OECOLOGIA Fredeen, A. L., Field, C. B. 1992; 92 (2): 207-214

  View details for Web of Science ID A1992JY89500010

• A NARROW-WAVEBAND SPECTRAL INDEX THAT TRACKS DIURNAL CHANGES IN PHOTOSYNTHETIC EFFICIENCY REMOTE SENSING OF ENVIRONMENT Gamon, J. A., Penuelas, J., Field, C. B. 1992; 41 (1): 35-44

  View details for Web of Science ID A1992HZ38800004

• EVIDENCE OF MULTIPLE CIRCADIAN OSCILLATORS IN BEAN-PLANTS JOURNAL OF BIOLOGICAL RHYTHMS HENNESSEY, T. L., Field, C. B. 1992; 7 (2): 105-113

  Abstract

  Circadian rhythms in stomatal opening and photosynthesis had shorter free-running periods than circadian rhythms in leaflet movement in bean plants (Phaseolus vulgaris L.) transferred from 12-hr photoperiods to constant conditions. The rhythm in leaflet movement had a period close to 27 hr, whereas the rhythm in stomatal opening, measured as conductance to water vapor, had a period close to 24 hr. Photosynthesis, measured as net assimilation of CO2, also oscillated with a period close to 24 hr. The periods of these rhythms did not vary with increasing temperature, demonstrating temperature compensation of the controlling oscillators. The difference in free-running periods displayed by these rhythms is evidence that multiple oscillators with different intrinsic frequencies operate in bean plants.

  View details for Web of Science ID A1992JA48800002

  View details for PubMedID 1611126

• RESPONSES OF TERRESTRIAL ECOSYSTEMS TO THE CHANGING ATMOSPHERE - A RESOURCE-BASED APPROACH ANNUAL REVIEW OF ECOLOGY AND SYSTEMATICS Field, C. B., Chapin, F. S., Matson, P. A., Mooney, H. A. 1992; 23: 201-235

  View details for Web of Science ID A1992JZ28100009

• RESPONSES OF PHOTOSYNTHESIS AND CARBOHYDRATE-PARTITIONING TO LIMITATIONS IN NITROGEN AND WATER AVAILABILITY IN FIELD-GROWN SUNFLOWER PLANT CELL AND ENVIRONMENT Fredeen, A. L., Gamon, J. A., Field, C. B. 1991; 14 (9): 963-970

  View details for Web of Science ID A1991GY05500010

• BIOCHEMICAL CORRELATES OF THE CIRCADIAN-RHYTHM IN PHOTOSYNTHESIS IN PHASEOLUS-VULGARIS PLANT PHYSIOLOGY Fredeen, A. L., HENNESSEY, T. L., Field, C. B. 1991; 97 (1): 415-419

  Abstract

  A circadian rhythm in photosynthesis occurs in Phaseolus vulgaris after transfer from a natural or artificial light:dark cycle to constant light. The rhythm in photosynthesis persists even when intercellular CO(2) partial pressure is held constant, demonstrating that the rhythm in photosynthesis is not entirely due to stomatal control over the diffusion of CO(2). Experiments were conducted to attempt to elucidate biochemical correlates with the circadian rhythm in photosynthesis. Plants were entrained to a 12-hour-day:12-hour-night light regimen and then monitored or sampled during a subsequent period of constant light. We observed circadian oscillations in ribulose-1,5-bisphosphate (RuBP) levels, and to a lesser extent in phosphoglyceric acid (PGA) levels, that closely paralleled oscillations in photosynthesis. However, the enzyme activity and activation state of the enzyme responsible for the conversion of RuBP to PGA, ribulose-1,5-bisphosphate carboxylase/oxygenase, showed no discernible circadian oscillation. Hence, we examined the possibility of circadian effects on RuBP regeneration. Neither ribulose-5-phosphate kinase activity nor the level of ATP fluctuated in constant light. Oscillations in triose-phosphate levels were out of phase with those observed for RuBP and PGA.

  View details for Web of Science ID A1991GJ79300060

  View details for PubMedID 16668402

• CIRCADIAN-RHYTHMS IN PHOTOSYNTHESIS - OSCILLATIONS IN CARBON ASSIMILATION AND STOMATAL CONDUCTANCE UNDER CONSTANT CONDITIONS PLANT PHYSIOLOGY HENNESSEY, T. L., Field, C. B. 1991; 96 (3): 831-836

  Abstract

  Net carbon assimilation and stomatal conductance to water vapor oscillated repeatedly in red kidney bean, Phaseolus vulgaris L., plants transferred from a natural photoperiod to constant light. In a gas exchange system with automatic regulation of selected environmental and physiological variables, assimilation and conductance oscillated with a free-running period of approximately 24.5 hours. The rhythms in carbon assimilation and stomatal conductance were closely coupled and persisted for more than a week under constant conditions. A rhythm in assimilation occurred when either ambient or intercellular CO(2) partial pressure was held constant, demonstrating that the rhythm in assimilation was not entirely the result of stomatal effects on CO(2) diffusion. Rhythms in assimilation and conductance were not expressed in plants grown under constant light at a constant temperature, demonstrating that the rhythms did not occur spontaneously but were induced by an external stimulus. In plants grown under constant light with a temperature cycle, a rhythm was entrained in stomatal conductance but not in carbon assimilation, indicating that the oscillators driving the rhythms differed in their sensitivity to environmental stimuli.

  View details for Web of Science ID A1991FX72500024

  View details for PubMedID 16668261

• LEAF RESPIRATION IN PIPER SPECIES NATIVE TO A MEXICAN RAIN-FOREST PHYSIOLOGIA PLANTARUM Fredeen, A. L., Field, C. B. 1991; 82 (1): 85-92

  View details for Web of Science ID A1991FR64000012

• EFFECTS OF LIGHT QUANTITY AND QUALITY AND SOIL-NITROGEN STATUS ON NITRATE REDUCTASE-ACTIVITY IN RAIN-FOREST SPECIES OF THE GENUS PIPER OECOLOGIA Fredeen, A. L., Griffin, K., Field, C. B. 1991; 86 (3): 441-446

  Abstract

  We studied nitrate reductase (NR) activity in six species of the genus Piper (Piperaceae) growing under a broad range of light availabilities. Field measurements were made on plants growing naturally in rainforest at the Los Tuxtlas Tropical Biological Preserve, Veracruz, Mexico at high- and lowlight extremes for each species. Foliar nitrogen on an area basis was positively related to the average daily photosynthetically active photon flux density (PFD) received by the leaf (r=0.76, p<0.01). In vivo NR activity was highly correlated with PFD (r=0.95, p<0.001) and less so with total leaf nitrogen (r=0.68, p<0.05). In vivo NR activity was always higher in high-light plants than in low-light plants within a species. Similarly, gap species such as P. auritum had much higher in vivo NR activities than shade species such as P. aequale. Soil NO 3- and NH 4+ pools and nitrogen-mineralization rates at Los Tuxtlas were similar between high- and low-light sites, indicating that the elevated NR activities in high-light plants were not the result of higher NO 3- availabilities in high-light microsites. We performed additional experiments at Stanford, California, USA on Piper plants grown at high- and low-light. Foliar NR was highly inducible by nitrate in the gap species (auritum) but not in the generalist (hispidum) or shade (aequale) species. Root NR activities were, in general, an order of magnitude lower than foliar activities. In total, these studies suggest that Piper gap species are inherently more competent to assimilate NO 3- and are better able to respond to sudden increases in NO 3- availability than are shade species.

  View details for Web of Science ID A1991FK48800021

• C in Hawaiian Metrosideros polymorpha: a case of internal resistance? Oecologia Vitousek, P. M., Field, C. B., Matson, P. A. 1990; 84 (3): 362-370

  Abstract

  Sun leaves of Metrosideros polymorpha were collected in 51 sites on 9 lava flows that represented gradients of elevation, precipitation, substrate age, and substrate texture on Mauna Loa volcano, Hawai'i. Leaf mass per unit leaf area increased with increasing elevation on all flows, while foliar nitrogen concentration decreased with increasing elevation and increased with increasing substrate age. Foliar δ(13)C became less negative with increasing elevation on the wet east-side lava flows, but not the dry northwest-side flows; it did not reflect patterns of precipitation or presumed water availability. δ(13)C was very strongly correlated with leaf mass per area across all of the sites. Limited gas-exchange information suggested that calculated ci/ca did not decrease with elevation in association with less-negative δ(13)C, and photosynthesis per unit of nitrogen was significantly reduced in high-elevation plants. These results are consistent with a substantial internal resistance to CO2 diffusion in the thick Metrosideros polymorpha leaves in high elevation sites.

  View details for DOI 10.1007/BF00329760

  View details for PubMedID 28313026

• VARIATION IN FOLIAR DELTA-C-13 IN HAWAIIAN METROSIDEROS-POLYMORPHA - A CASE OF INTERNAL RESISTANCE OECOLOGIA Vitousek, P. M., Field, C. B., Matson, P. A. 1990; 84 (3): 362-370

  Abstract

  Sun leaves of Metrosideros polymorpha were collected in 51 sites on 9 lava flows that represented gradients of elevation, precipitation, substrate age, and substrate texture on Mauna Loa volcano, Hawai'i. Leaf mass per unit leaf area increased with increasing elevation on all flows, while foliar nitrogen concentration decreased with increasing elevation and increased with increasing substrate age. Foliar δ(13)C became less negative with increasing elevation on the wet east-side lava flows, but not the dry northwest-side flows; it did not reflect patterns of precipitation or presumed water availability. δ(13)C was very strongly correlated with leaf mass per area across all of the sites. Limited gas-exchange information suggested that calculated ci/ca did not decrease with elevation in association with less-negative δ(13)C, and photosynthesis per unit of nitrogen was significantly reduced in high-elevation plants. These results are consistent with a substantial internal resistance to CO2 diffusion in the thick Metrosideros polymorpha leaves in high elevation sites.

  View details for Web of Science ID A1990EC00700009

• REMOTE-SENSING OF THE XANTHOPHYLL CYCLE AND CHLOROPHYLL FLUORESCENCE IN SUNFLOWER LEAVES AND CANOPIES OECOLOGIA Gamon, J. A., Field, C. B., Bilger, W., Bjorkman, O., Fredeen, A. L., Penuelas, J. 1990; 85 (1): 1-7

  View details for Web of Science ID A1990EJ23000001

• LOW AND HIGH-TEMPERATURE LIMITS TO PSII - A SURVEY USING TRANS-PARINARIC ACID, DELAYED LIGHT-EMISSION, AND F0 CHLOROPHYLL FLUORESCENCE PLANT PHYSIOLOGY Terzaghi, W. B., FORK, D. C., Berry, J. A., Field, C. B. 1989; 91 (4): 1494-1500

  Abstract

  Many studies have shown that membrane lipids of chilling-sensitive plants begin lateral phase separation (i.e. a minor component begins freezing) at chilling temperatures and that chilling-sensitive plants are often of tropical origin. We tested the hypothesis that membranes of tropical plants begin lateral phase separation at chilling temperatures, and that plants lower the temperature of lateral phase separation as they invade cooler habitats. To do so we studied plant species in one family confined to the tropics (Piperaceae) and in three families with both tropical and temperate representatives (Fabaceae [Leguminosae], Malvaceae, and Solanaceae). We determined lateral phase separation temperatures by measuring the temperature dependence of fluorescence from trans-parinaric acid inserted into liposomes prepared from isolated membrane phospholipids. In all families we detected lateral phase separations at significantly higher temperatures, on average, in species of tropical origin. To test for associated physiological effects we measured the temperature dependence of delayed light emission (DLE) by discs cut from the same leaves used for lipid analysis. We found that the temperature of maximum DLE upon chilling was strongly correlated with lateral phase separation temperatures, but was on average approximately 4 degrees C lower. We also tested the hypothesis that photosystem II (PSII) (the most thermolabile component of photosynthesis) of tropical plants tolerates higher temperatures than PSII of temperate plants, using DLE and F(o) chlorophyll fluorescence upon heating to measure the temperature at which PSII thermally denatured. We found little difference between the two groups in PSII denaturation temperature. We also found that the temperature of maximum DLA upon heating was not significantly different from the critical temperature for F(o) fluorescence. Our results indicate that plants lowered their membrane freezing temperatures as they radiated from their tropical origins. One interpretation is that the tendency for membranes to begin freezing at chilling temperatures is the primitive condition, which plants corrected as they invaded colder habitats. An alternative is that membranes which freeze at temperatures only slightly lower than the minimum growth temperature confer an advantage.

  View details for Web of Science ID A1989CG37300043

  View details for PubMedID 16667207

• THE DEPENDENCE OF PLANT-ROOT - SHOOT RATIOS ON INTERNAL NITROGEN CONCENTRATION ANNALS OF BOTANY Levin, S. A., Mooney, H. A., Field, C. 1989; 64 (1): 71-75

  View details for Web of Science ID A1989AJ96300011

• RELATIONSHIPS AMONG LEAF CONSTRUCTION COST, LEAF LONGEVITY, AND LIGHT ENVIRONMENT IN RAIN-FOREST PLANTS OF THE GENUS PIPER AMERICAN NATURALIST Williams, K., Field, C. B., Mooney, H. A. 1989; 133 (2): 198-211

  View details for Web of Science ID A1989T251800004

• INTERACTIONS BETWEEN CROWN STRUCTURE AND LIGHT ENVIRONMENT IN 5 RAIN-FOREST PIPER SPECIES AMERICAN JOURNAL OF BOTANY Chazdon, R. L., Williams, K., Field, C. B. 1988; 75 (10): 1459-1471

  View details for Web of Science ID A1988Q650300002

• PHOTOGRAPHIC ESTIMATION OF PHOTOSYNTHETICALLY ACTIVE RADIATION - EVALUATION OF A COMPUTERIZED TECHNIQUE OECOLOGIA Chazdon, R. L., Field, C. B. 1987; 73 (4): 525-532

  View details for Web of Science ID A1987K285600008

• DETERMINANTS OF PHOTOSYNTHETIC CAPACITY IN 6 RAIN-FOREST PIPER SPECIES OECOLOGIA Chazdon, R. L., Field, C. B. 1987; 73 (2): 222-230

  View details for Web of Science ID A1987J748000009

• LEAF CARBON ISOTOPE RATIOS OF PLANTS FROM A SUBTROPICAL MONSOON FOREST OECOLOGIA Ehleringer, J. R., Lin, Z. F., Field, C. B., Sun, G. C., Kuo, C. Y. 1987; 72 (1): 109-114

  View details for Web of Science ID A1987G796100018

• Midday wilting in a tropical pioneer tree FUNCTIONAL ECOLOGY Chiariello, N. R., Field, C. B., Mooney, H. A. 1987; 1 (1): 3-11

  View details for Web of Science ID 000208583900002

• PLANT-RESPONSES TO MULTIPLE ENVIRONMENTAL-FACTORS BIOSCIENCE Chapin, F. S., Bloom, A. J., Field, C. B., Waring, R. H. 1987; 37 (1): 49-57

  View details for Web of Science ID A1987F421700010

• LEAF CARBON ISOTOPE AND MINERAL-COMPOSITION IN SUBTROPICAL PLANTS ALONG AN IRRADIANCE CLINE OECOLOGIA Ehleringer, J. R., Field, C. B., Lin, Z. F., Kuo, C. Y. 1986; 70 (4): 520-526

  View details for Web of Science ID A1986E694200007

• CONSTRUCTION AND MAINTENANCE COSTS OF MEDITERRANEAN-CLIMATE EVERGREEN AND DECIDUOUS LEAVES .2. BIOCHEMICAL PATHWAY ANALYSIS ACTA OECOLOGICA-OECOLOGIA PLANTARUM Merino, J., Field, C., Mooney, H. A. 1984; 5 (3): 211-229

  View details for Web of Science ID A1984TC30200001

• Compromises between water-use efficiency and nitrogen-use efficiency in five species of California evergreens. Oecologia Field, C., Merino, J., Mooney, H. A. 1983; 60 (3): 384-389

  Abstract

  In five California evergreen trees and shrubs cooccurring in this study but most common in habitats of different moisture availability, leaf nitrogen was a major determinant of photosynthetic capacity. Within each species, stomatal conductance was highly correlated with photosynthetic capacity, resulting in little variation in the concentration of CO2 in the intercellular spaces. Among species, intercellular CO2 concentrations varied significantly. Under controlled conditions, the leaves that realized the highest photosynthesis per unit of leaf nitrogen tended to realize the lowest photosynthesis per unit of water transpired. The ratio of photosynthesis to transpiration, an instantaneous measure of intrinsic water-use efficiency, was highest in the species commonly found in the direst habitats and lowest in the species most common in the wettes habitats.

  View details for DOI 10.1007/BF00376856

  View details for PubMedID 28310700

• Photosynthetic characteristic of South African sclerophylls. Oecologia Mooney, H. A., Field, C., Gulmon, S. L., Rundel, P., Kruger, F. J. 1983; 58 (3): 398-401

  Abstract

  Sclerophyll shrubs of the South African mountain fynbos have leaves similar in structural and physiological properties to leaves from evergreen shrubs of other mediterranean-climate regions. These leaves have relatively low photosynthetic capacities (<14 μmol CO2 m-2 s-1), and are light saturated at relatively low photon irradiances (<1.0 mmol m-2 s-1). They have broad temperature responses of photosynthesis, moderate water-use efficiencies (∼0.003 mol CO2/mol H2O), high specific weights (∼200 g m-2) and low nitrogen contents (∼10 mg g-1).

  View details for DOI 10.1007/BF00385242

  View details for PubMedID 28310341

• Photosynthetic characteristics of plants of a Californian cool coastal environment. Oecologia Mooney, H. A., Field, C., Williams, W. E., Berry, J. A., Björkman, O. 1983; 57 (1-2): 38-42

  Abstract

  Herbaceous perennials native to coastal bluffs in northern California all had similar photosynthetic characteristics: moderate photosynthetic capacities, light saturation at relatively low irradiances, and low photosynthetic temperature optima. They all decreased stomatal conductance in response to decreased humidity. Though the coastal habitat generally has high humidities and cool air temperatures leaf microclimatic conditions lead frequently to large vapor-concentration gradients between leaf and air. Stomatal sensitivty to the vapor-concentration gradient may result in important plant-water conservation in this summer drought habitat.

  View details for DOI 10.1007/BF00379559

  View details for PubMedID 28310154

• Leaf age and seasonal effects on light, water, and nitrogen use efficiency in a California shrub. Oecologia Field, C., Mooney, H. A. 1983; 56 (2-3): 348-355

  Abstract

  Photosynthetic capacity, leaf nitrogen content, and stomatal conductance decreased with increasing leaf age in the chaparral shrub, Lepechinia calycina, growing in its natural habitat. Efficiency of resource use for three resources that potentially limit photosynthesis did not, however, decrease with increasing leaf age. Light-use efficiency, given by the quantum yield of photosynthesis at low light intensities, was unaffected by leaf aging but decreased slightly through the winter and spring growing season. Water-use efficiency, the ratio of photosynthesis to transpiration at light saturation and with a constant water vapor concentration gradient, was not affected by leaf aging or seasonal change. Nitrogen-use efficiency, the ratio of photosynthesis at light saturation to leaf nitrogen content did not change with leaf age but was lower in the leaves with the highest specific weights. This ensemble of leaf-age effects is consistent with the hypothesis that aging represents resource redistribution and not uncontrolled deterioration.

  View details for DOI 10.1007/BF00379711

  View details for PubMedID 28310215

• Allocating leaf nitrogen for the maximization of carbon gain: Leaf age as a control on the allocation program. Oecologia Field, C. 1983; 56 (2-3): 341-347

  Abstract

  Simulations using a biochemically-based model of leaf photosynthesis make it possible to predict the distribution of leaf nitrogen contents that maximizes photosynthetic carbon gain over the canopy of an entire plant. In general, the optimal nitrogen content increased with increasing daily photosynthetically active photon irradiance.Leaf aging in natural environments tended to produce leaf nitrogen contents that were similar to the optimal values but somewhat more clustered. Nitrogen redistribution over the duration of a leaf involves costs that are smaller than the benefits in increased photosynthesis. The costs could become larger than the benefits if nitrogen were redistributed on a shorter time scale.

  View details for DOI 10.1007/BF00379710

  View details for PubMedID 28310214

• ALLOCATING LEAF NITROGEN FOR THE MAXIMIZATION OF CARBON GAIN - LEAF AGE AS A CONTROL ON THE ALLOCATION PROGRAM OECOLOGIA Field, C. 1983; 56 (2-3): 341-347

  View details for Web of Science ID A1983QD66500028

• LEAF AGE AND SEASONAL EFFECTS ON LIGHT, WATER, AND NITROGEN USE EFFICIENCY IN A CALIFORNIA SHRUB OECOLOGIA Field, C., Mooney, H. A. 1983; 56 (2-3): 348-355

  View details for Web of Science ID A1983QD66500029

• PHOTOSYNTHETIC CHARACTERISTICS OF PLANTS OF A CALIFORNIAN COOL COASTAL ENVIRONMENT OECOLOGIA Mooney, H. A., Field, C., Williams, W. E., Berry, J. A., Bjorkman, O. 1983; 57 (1-2): 38-42

  View details for Web of Science ID A1983QG36400007

• COMPROMISES BETWEEN WATER-USE EFFICIENCY AND NITROGEN-USE EFFICIENCY IN 5 SPECIES OF CALIFORNIA EVERGREENS OECOLOGIA Field, C., Merino, J., Mooney, H. A. 1983; 60 (3): 384-389

  View details for Web of Science ID A1983RV18900018

• PHOTOSYNTHETIC CHARACTERISTIC OF SOUTH-AFRICAN SCLEROPHYLLS OECOLOGIA Mooney, H. A., Field, C., GULMON, S. L., Rundel, P., Kruger, F. J. 1983; 58 (3): 398-401

  View details for Web of Science ID A1983QY89200019

• ENVIRONMENTAL CONTROLS ON STOMATAL CONDUCTANCE IN A SHRUB OF THE HUMID TROPICS PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES Mooney, H. A., Field, C., YANES, C. V., Chu, C. 1983; 80 (5): 1295-1297

  Abstract

  Leaves of Piper hispidum, a shrub native to the lowland tropics of Mexico, have a strong stomatal response to humidity that results in similar rates of water loss under a wide range of leaf-to-air water-vapor concentration gradients. Stomatal conductance of these leaves is insensitive to CO(2) concentration and increases in response to high humidity even in the dark.

  View details for PubMedID 16593286

• Determinants of leaf temperature in California Mimulus species at different altitudes. Oecologia Field, C., Chiariello, N., Williams, W. E. 1982; 55 (3): 414-420

  Abstract

  Leaf energy balance and gas-exchange characteristics were studied in Mimulus cardinalis at 400 m and Mimulus lewisii at 2,700 m in the Sierra Nevada of central California. In contrast to previous observations, leaf temperatures were not near 30° C at air temperatures from 20 to 40° C but were coupled quite closely to air temperature. Stomatal conductance in both species decreased in response to increases in the water vapor concentration gradient, a response opposite that required to establish 30°C leaf temperatures over a wide range of air temperatures. The temperature optima for photosynthesis were broad in both species but 5° C higher for M. cardinalis than for M. lewisii. The direct or indirect effects of altitude did not contribute significantly to the maintenance of constant leaf temperatures. For both species, maintaining constant leaf temperatures appears to be less important than avoiding inhibitory water stress or diffusion limitation of photosynthesis.

  View details for DOI 10.1007/BF00376931

  View details for PubMedID 28309984

• PHOTOCONTROL OF THE FUNCTIONAL COUPLING BETWEEN PHOTOSYNTHESIS AND STOMATAL CONDUCTANCE IN THE INTACT LEAF - BLUE-LIGHT AND PAR-DEPENDENT PHOTOSYSTEMS IN GUARD-CELLS PLANT PHYSIOLOGY Zeiger, E., Field, C. 1982; 70 (2): 370-375

  Abstract

  The photocontrol of the functional coupling between photosynthesis and stomatal conductance in the leaf was investigated in gas exchange experiments using monochromatic light provided by lasers. Net photosynthesis and stomatal conductance were measured in attached leaves of Malva parviflora L. as a function of photon irradiance at 457.9 and 640.0 nanometers.Photosynthetic rates and quantum yields of photosynthesis were higher under red light than under blue, on an absorbed or incident basis.Stomatal conductance was higher under blue than under red light at all intensities. Based on a calculated apparent photon efficiency of conductance, blue and red light had similar effects on conductance at intensities higher than 0.02 millimoles per square meter per second, but blue light was several-fold more efficient at very low photon irradiances. Red light had no effect on conductance at photon irradiances below 0.02 millimoles per square meter per second. These observations support the hypothesis that stomatal conductance is modulated by two photosystems: a blue light-dependent one, driving stomatal opening at low light intensities and a photosynthetically active radiation (PAR)-dependent one operating at higher irradiances.When low intensity blue light was used to illuminate a leaf already irradiated with high intensity, 640 nanometers light, the leaf exhibited substantial increases in stomatal conductance. Net photosynthesis changed only slightly. Additional far-red light increased net photosynthesis without affecting stomatal conductance. These observations indicate that under conditions where the PAR-dependent system is driven by high intensity red light, the blue light-dependent system has an additive effect on stomatal conductance.The wavelength dependence of photosynthesis and stomatal conductance demonstrates that these processes are not obligatorily coupled and can be controlled by light, independent of prevailing levels of intercellular CO(2). The blue light-dependent system in the guard cells may function as a specific light sensor while the PAR-dependent system supplies a CO(2)-modulated energy source providing functional coupling between the guard cells and the photosynthesizing mesophyll.

  View details for Web of Science ID A1982PE11100010

  View details for PubMedID 16662498

• exchange analysis. Oecologia Merino, J., Field, C., Mooney, H. A. 1982; 53 (2): 208-213

  Abstract

  Gas exchange and leaf growth analysis were used in conjunction to determine leaf-construction and maintenance costs in three co-occurring shrubs of the california chaparral, one evergreen, Heteromeles arbutifolia, and two drougth deciduous species, Lepechinia calycina, and Diplacus aurantiacus. The construction costs per unit of leaf weight were similar among the three species and very close to values reported for other evergreens but considerably higher than leaf construction costs for other deciduous or herbaceous plants. Maintenance costs per unit of leaf weight were significantly greater in one deciduous species, L. calycina, than in the evergreen. Maintenance costs for all species were in the range reported for herbaceous species and considerably above those reported for other evergreens.

  View details for DOI 10.1007/BF00545665

  View details for PubMedID 28311111

• CONSTRUCTION AND MAINTENANCE COSTS OF MEDITERRANEAN-CLIMATE EVERGREEN AND DECIDUOUS LEAVES .1. GROWTH AND CO2 EXCHANGE ANALYSIS OECOLOGIA Merino, J., Field, C., Mooney, H. A. 1982; 53 (2): 208-213

  View details for Web of Science ID A1982NR56400010

• DETERMINANTS OF LEAF TEMPERATURE IN CALIFORNIA MIMULUS SPECIES AT DIFFERENT ALTITUDES OECOLOGIA Field, C., Chiariello, N., Williams, W. E. 1982; 55 (3): 414-420

  View details for Web of Science ID A1982PS69800020

• A PORTABLE SYSTEM FOR MEASURING CARBON-DIOXIDE AND WATER-VAPOR EXCHANGE OF LEAVES PLANT CELL AND ENVIRONMENT Field, C., Berry, J. A., Mooney, H. A. 1982; 5 (2): 179-186

  View details for Web of Science ID A1982NL68100009

• Photosynthetic capacity in relation to leaf position in desert versus old-field annuals. Oecologia Mooney, H. A., Field, C., Gulmon, S. L., Bazzaz, F. A. 1981; 50 (1): 109-112

  Abstract

  Desert annuals of Death Valley, California have higher average light-saturated photosynthetic capacities and leaf nitrogen contents than do early-successional annuals of Illinois. The leaves of annuals in the light-unlimited Death Valley environment change little in specific weight, nitrogen, or photosynthetic capacity with age. In contrast, these properties decrease markedly with age in the leaves of the Illinois annuals even in leaves not exposed to the usual shading that accompanies canopy development. These results are interpreted in a carbon-gained-per-nitrogen-invested context.

  View details for DOI 10.1007/BF00378802

  View details for PubMedID 28310070

• PHOTOSYNTHETIC CAPACITY IN RELATION TO LEAF POSITION IN DESERT VERSUS OLD-FIELD ANNUALS OECOLOGIA Mooney, H. A., Field, C., GULMON, S. L., Bazzaz, F. A. 1981; 50 (1): 109-112

  View details for Web of Science ID A1981MD22000015