Plant nutrient acquisition under elevated CO2 and implications for the land carbon sink

Abstract

Terrestrial ecosystems currently sequester around one-third of the anthropogenic carbon emitted each year, slowing the pace of climate change. However, the future of this sink under rising atmospheric CO2 concentrations remains uncertain, in part due to the impact that nutrient limitation may have on plant biomass. Here we review plant nutrient acquisition strategies and evidence of the enhanced utilization of these strategies under experimental and real-world elevated CO2. Many of the strategies that are key to alleviating nutrient limitation under elevated CO2 are not well represented in current Earth system models, and a simple data-driven analysis implies that models that do not account for nutrient acquisition strategies could underestimate the land sink. Elevated atmospheric CO2 has stimulated plant growth, yet the future land carbon sink may be constrained in part by nutrient availability. Here the authors review plant nutrient acquisition strategies and the need for better representation in models to improve predictions of land carbon uptake.