Opposing seasonal temperature dependencies of <scp>CO<sub>2</sub></scp> and <scp>CH<sub>4</sub></scp> emissions from wetlands
Jinquan Li, Junmin Pei, Changming Fang, Bo Li, Ming Nie
Abstract
Abstract Wetlands are critically important to global climate change because of their role in modulating the release of atmospheric greenhouse gases (GHGs) carbon dioxide (CO 2 ) and methane (CH 4 ). Temperature plays a crucial role in wetland GHG emissions, while the general pattern for seasonal temperature dependencies of wetland CO 2 and CH 4 emissions is poorly understood. Here we show opposite seasonal temperature dependencies of CO 2 and CH 4 emissions by using 36,663 daily observations of simultaneous measurements of ecosystem‐scale CO 2 and CH 4 emissions in 42 widely distributed wetlands from the FLUXNET‐CH 4 database. Specifically, the temperature dependence of CO 2 emissions decreased with increasing monthly mean temperature, but the opposite was true for that of CH 4 emissions. Neglecting seasonal temperature dependencies may overestimate wetland CO 2 and CH 4 emissions compared to the use of a year‐based static and consistent temperature dependence parameter when only considering temperature effects. Our findings highlight the importance of incorporating the remarkable seasonality in temperature dependence into process‐based biogeochemical models to predict feedbacks of wetland GHG emissions to climate warming.