Kabir Peay, Postdoctoral Faculty Sponsor
- Ectomycorrhizal root tips harbor distinctive fungal associates along a soil nitrogen gradient FUNGAL ECOLOGY 2021; 54
Decay by ectomycorrhizal fungi couples soil organic matter to nitrogen availability
2022; 25 (2): 391-404
Interactions between soil nitrogen (N) availability, fungal community composition, and soil organic matter (SOM) regulate soil carbon (C) dynamics in many forest ecosystems, but context dependency in these relationships has precluded general predictive theory. We found that ectomycorrhizal (ECM) fungi with peroxidases decreased with increasing inorganic N availability across a natural inorganic N gradient in northern temperate forests, whereas ligninolytic fungal saprotrophs exhibited no response. Lignin-derived SOM and soil C were negatively correlated with ECM fungi with peroxidases and were positively correlated with inorganic N availability, suggesting decay of lignin-derived SOM by these ECM fungi reduced soil C storage. The correlations we observed link SOM decay in temperate forests to tradeoffs in tree N nutrition and ECM composition, and we propose SOM varies along a single continuum across temperate and boreal ecosystems depending upon how tree allocation to functionally distinct ECM taxa and environmental stress covary with soil N availability.
View details for DOI 10.1111/ele.13923
View details for Web of Science ID 000719401800001
View details for PubMedID 34787356
- From DNA sequences to microbial ecology: Wrangling NEON soil microbe data with the neonMicrobe R package ECOSPHERE 2021; 12 (11)
Ectomycorrhizal access to organic nitrogen mediates CO2 fertilization response in a dominant temperate tree.
2021; 12 (1): 5403
Plant-mycorrhizal interactions mediate plant nitrogen (N) limitation and can inform model projections of the duration and strength of the effect of increasing CO2 on plant growth. We present dendrochronological evidence of a positive, but context-dependent fertilization response of Quercus rubra L. to increasing ambient CO2 (iCO2) along a natural soil nutrient gradient in a mature temperate forest. We investigated this heterogeneous response by linking metagenomic measurements of ectomycorrhizal (ECM) fungal N-foraging traits and dendrochronological models of plant uptake of inorganic N and N bound in soil organic matter (N-SOM). N-SOM putatively enhanced tree growth under conditions of low inorganic N availability, soilconditions where ECM fungal communities possessed greater genomic potential to decay SOM and obtain N-SOM. These trees were fertilized by 38 years of iCO2. In contrast, trees occupying inorganic N rich soils hosted ECM fungal communities with reduced SOM decay capacity and exhibited neutral growth responses to iCO2. This study elucidates how the distribution of N-foraging traits among ECM fungal communities govern tree access to N-SOM and subsequent growth responses to iCO2.
View details for DOI 10.1038/s41467-021-25652-x
View details for PubMedID 34518539
- Coupled Shifts in Ectomycorrhizal Communities and Plant Uptake of Organic Nitrogen Along a Soil Gradient: An Isotopic Perspective ECOSYSTEMS 2021
- Variation in the Size-Structure of Dominant Branching Coral Taxa (Acroporidae: Acropora) and (Pocilloporidae: Pocillopora) in New Ireland Province, Papua New Guinea PACIFIC SCIENCE 2020; 74 (3): 283–96