Ecosystem responses to elevated CO2 are governed by plant-soil interactions and the cost of nitrogen acquisition

How does the cost of nitrogen acquisition affect how an ecosystem responds to elevated CO₂? Terrer et al. have addressed this question in a comprehensive review of findings from elevated CO₂ experiments, using a plant economics framework. The authors describe ecosystem responses, particularly those of plants to elevated CO₂, by interactions with mycorrhizal fungi and symbiotic N-fixing microbes, and explain these responses as a relationship between costs and benefits. These established interactions that allow N-acquisition positively correlate with plant growth and photosynthetic capacity and have a negative co-relation with carbon storage. The review summarizes that the predicted models which aim to improve the carbon feedback loop as a result of elevated CO₂ emissions may be improved by treating N as a resource for plants that can be acquired at the expense of enregy, and will have lower costs depending upon the status of the plant-microbe symbiosis. (Summary by Amey Redkar) New Phytol.  10.1111/nph.14872/full