Variations in terrestrial oxygen sources under climate change  

作　　者：Lei DING Jianping HUANG Changyu LI Dongliang HAN Xiaoyue LIU Haiyun LI Yan BAI Jiping HUANG 

机构地区：[1]College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,China [2]Collaborative Innovation Center for Western Ecological Safety,Lanzhou University,Lanzhou 730000,China [3]Enlightening Bioscience Research Center,Mississauga L4X 2X7,Canada

出　　处：《Science China Earth Sciences》2022年第9期1810-1823,共14页中国科学（地球科学英文版）

基　　金：jointly supported by the National Natural Science Foundation of China (Grant Nos. 41521004 and 41991231);the China University Research Talents Recruitment Program (Grant No. B13045);the Fundamental Research Funds for the Central Universities (Grant Nos. lzujbky-2021-kb12 and lzujbky-2021-63)。

摘　　要：The terrestrial ecosystem is an important source of atmospheric oxygen, and its changes are closely related to variations in atmospheric oxygen level. However, few studies have focused on the characteristics and driving forces behind terrestrial ecosystem oxygen sources. In this study, based on observations and net carbon flux simulations from the Sixth Coupled Model Intercomparison Project, we investigated temporal and spatial variations in terrestrial oxygen sources. As the largest source of atmospheric oxygen, the terrestrial ecosystem can produce approximately 7.10±0.38 gigatons of oxygen per year, and the tropics are the main oxygen producing regions. Notably, there are many “non-oxygen-producing lands”, where the lands no longer provide oxygen to the atmosphere, located in the high latitudes and around the deserts of Central Asia. Long-term analysis reveals that anthropogenic activities and climate change are responsible for the variations in terrestrial oxygen sources owing to land-use changes and competing effects between net photosynthesis and heterotrophic respiration. By 2100, more oxygen will be produced from the low-middle latitudes, while the high latitudes will serve as a larger oxygen sink due to extreme land-use type changes and drastic increases in soil respiration. Through this study, we supplement the understanding of the modern oxygen cycle and help provide better estimates for future variations in atmospheric oxygen level.

关 键 词：Oxygen cycle Terrestrial ecosystem CMIP6 Anthropogenic forcing Climate change 

分 类 号：P467[天文地球—大气科学及气象学]