The impacts of climate change and human activities on biogeochemical cycles on the Qinghai-Tibetan Plateau

• Published in: Global change biology Vol. 19; no. 10; pp. 2940 - 2955
• Main Authors: Chen, Huai, Zhu, Qiuan, Peng, Changhui, Wu, Ning, Wang, Yanfen, Fang, Xiuqing, Gao, Yongheng, Zhu, Dan, Yang, Gang, Tian, Jianqing, Kang, Xiaoming, Piao, Shilong, Ouyang, Hua, Xiang, Wenhua, Luo, Zhibin, Jiang, Hong, Song, Xingzhang, Zhang, Yao, Yu, Guirui, Zhao, Xinquan, Gong, Peng, Yao, Tandong, Wu, Jianghua
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.10.2013; Wiley-Blackwell
• Subjects: Agriculture; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Biogeochemical cycles; Biogeochemistry; Biological and medical sciences; carbon budget; Carbon dioxide; China; Climate Change; Climatology. Bioclimatology. Climate change; Earth, ocean, space; Ecosystem; Ecosystem models; Emissions; Environmental impact; Exact sciences and technology; External geophysics; Fundamental and applied biological sciences. Psychology; General aspects; Glaciers; Global warming; Human influences; Humans; ice retreat; intact ecosystems; land use change; Meteorology; Methane; Nitrous oxide; Permafrost; Plants; Primary production; Synecology; Thawing; Tibet; Central Asia; Asia; China; Tibet; ice retreat; intact ecosystems; carbon budget; Ice; Permafrost; Biogeochemical cycle; Carbon; Land use; Dynamical climatology; Climate change; Tibetan Plateau; Human activity; Ecosystem; land use change; Anthropogenic factor; permafrost
• ISSN: 1354-1013; 1365-2486; 1365-2486
• DOI: 10.1111/gcb.12277

With a pace of about twice the observed rate of global warming, the temperature on the Qinghai‐Tibetan Plateau (Earth's ‘third pole’) has increased by 0.2 °C per decade over the past 50 years, which results in significant permafrost thawing and glacier retreat. Our review suggested that warming enhanced net primary production and soil respiration, decreased methane (CH4) emissions from wetlands and increased CH4 consumption of meadows, but might increase CH4 emissions from lakes. Warming‐induced permafrost thawing and glaciers melting would also result in substantial emission of old carbon dioxide (CO2) and CH4. Nitrous oxide (N2O) emission was not stimulated by warming itself, but might be slightly enhanced by wetting. However, there are many uncertainties in such biogeochemical cycles under climate change. Human activities (e.g. grazing, land cover changes) further modified the biogeochemical cycles and amplified such uncertainties on the plateau. If the projected warming and wetting continues, the future biogeochemical cycles will be more complicated. So facing research in this field is an ongoing challenge of integrating field observations with process‐based ecosystem models to predict the impacts of future climate change and human activities at various temporal and spatial scales. To reduce the uncertainties and to improve the precision of the predictions of the impacts of climate change and human activities on biogeochemical cycles, efforts should focus on conducting more field observation studies, integrating data within improved models, and developing new knowledge about coupling among carbon, nitrogen, and phosphorus biogeochemical cycles as well as about the role of microbes in these cycles.