Oceanography and Atmospheric Sciences and Meteorology Commons^™

Asynchronous Nitrogen Supply And Demand Produce Nonlinear Plant Allocation Responses To Warming And Elevated Co2, Genevieve L. Noyce, Matthew L. Kirwan, Roy L. Rich, J. Patrick Megonigal

VIMS Articles

Terrestrial ecosystem responses to climate change are mediated by complex plant–soil feedbacks that are poorly understood, but often driven by the balance of nutrient supply and demand. We actively increased aboveground plant-surface temperature, belowground soil temperature, and atmospheric CO₂ in a brackish marsh and found nonlinear and nonadditive feedbacks in plant responses. Changes in root-to-shoot allocation by sedges were nonlinear, with peak belowground allocation occurring at +1.7 °C in both years. Above 1.7 °C, allocation to root versus shoot production decreased with increasing warming such that there were no differences in root biomass between ambient and +5.1 °C plots …