被高估的全球土壤异养呼吸

作     者：何悦 丁金枝 Yue He;Jinzhi Ding

作者机构：Sino-French Institute for Earth System ScienceCollege of Urban and Environmental SciencesPeking UniversityBeijing 100871China State Key Laboratory of Tibetan Plateau Earth SystemResources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China 

出 版 物：《Science Bulletin》 (科学通报（英文版）)

年 卷 期：2022年第67卷第3期

页      面：223-225页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 083001[工学-环境科学] 07[理学] 08[工学] 070602[理学-大气物理学与大气环境] 0706[理学-大气科学] 0713[理学-生态学] 

基　　金：the National Natural Science Foun-dation of China(42022004 and 41901085) the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0606)。 

主　　题：soil 土壤异养呼吸 estimates 

摘      要：Soil heterotrophic respiration(Rh)is the flux of CO2 that microbes and soil fauna release to the atmosphere by extracting the energy of organic molecules that they break down[1].Rh closes the terrestrial carbon cycle by recycling more than 70%of the annual total fixed carbon to the atmosphere per year so that it can be reused by plants for photosynthesis[2].Rh plays a key role in regulating the changes in atmospheric CO2 concentrations as well as the consequential climate feedbacks[3,4].However,global Rh estimates suffer from large uncertainty.The simulated global Rh value ranges from 30 to 64 Pg C a-1 by MsTMIP models[5],from 47 to 72 Pg C a-1 by Trendy models[6],and from 42 to 73 Pg C a-1 by CMIP5 models[1].High spatial heterogeneity and the close contingency of soil decomposition on environmental changes,such as temperature and soil moisture,may be a response to such great unpredictability[7].Rh is highly transient and variable at diurnal,seasonal and multiyear scales.Short-term observations and limited in situ measurements,as well as low representativeness in many key regions with high soil carbon stocks and difficult accessibilities,such as the northern circumpolar permafrost region and high-altitude Tibetan region,make Rh the most unpredictable process in land-carbon cycle models[8].Accurate estimates of Rh at regional and global scales are thus imperative to quantify the land carbon sink,to evaluate land-carbon cycle models and to define baselines for climate change mitigation efforts.