Higher temperature sensitivity of forest soil methane oxidation in colder climates
Baizhi Jiang, Hongyang Chen, Zhenyu Wei, Junqi Zhang, Muxi Guo, Taoge Yang, Xuhui Zhou
Abstract
Forest soils, serving as an important sink for atmospheric methane (CH4), modulate the global CH4 budget. However, the direction and magnitude of the forest soil CH4 sink under warming remain uncertain, partly because the temperature response of microbial CH4 oxidation varies substantially across geographical scales. Here, we reveal the spatial variation in the response of forest soil microbial CH4 oxidation to warming, along with the driving factors, across 84 sites spanning a broad latitudinal gradient in eastern China. Our results show that the temperature sensitivity of soil microbial CH4 oxidation significantly declines with increasing site mean annual temperature, with a range of 0.03 to 0.77 μg CH4 g–1 soil d–1 °C–1. Moreover, soil resources and type II methanotrophs play crucial roles in shaping the temperature sensitivity of soil microbial CH4 oxidation. Our findings highlight the importance of incorporating climate, soil resources, and methanotroph groups into biogeochemical models to more realistically predict forest soil CH4 sink under warming. Forest soils are vital in regulating the atmospheric CH4 budget, but their response to warming varies spatially. The authors assess the temperature response of soil microbial CH4 oxidation across 84 forest sites in China, finding higher temperature sensitivity in colder regions, indicating greater CH4 sink potential in these areas with warming.