Black carbon record of the wildfire history of western Sichuan Province in China over the last 12.8 ka  

作　　者：Weiwei SUN Enlou ZHANG Ji SHEN Rong CHEN Enfeng LIU 

机构地区：[1]State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China [2]University of Chinese Academy of Sciences, Beijing 100049, China

出　　处：《Frontiers of Earth Science》2016年第4期634-643,共10页地球科学前沿（英文版）

基　　金：Acknowledgements We thank three anonymous reviewers who gave us important advice which improved the quality of the manuscript. We also thank Dr. Jan Bloemendal for correcting the English language, and Dr. Q Jiang, Dr. H Tang for field assistance. This project was supported by the Strategic Priority Research Program-Climate Change： Carbon Budget and Relevant Issues of the Chinese Academy of Sciences （Grant No. XDA05120102） and NIGLAS （2012135004）, and the National Natural Science Foundation of China （Grant No. 41272380）.

摘　　要：Wildfire is recognized as a critical Earth system process which affects the global carbon cycle, atmospheric chemistry, and ecosystem dynamics. Estimat- ing the potential impact of future climate change on the incidence of fire requires an understanding of the long-term interactions of fire, climate, vegetation, and human activity. Accordingly, we analyzed the black carbon content and the pollen stratigraphy of sediments spanning the past 12.8 ka from Lake Muge Co, an alpine lake in western Sichuan Province, in order to determine the main factors influen- cing regional fire regimes. The resuks demonstrate that wildfires occurred frequently and intensively during the late deglaciation and the early Holocene when the regional vegetation was dominated by deciduous forests. Wildfire occurrence decreased significantly during the Holocene climatic optimum between 9.2 and 5.6 cal ka BP. Overall, the wildfire history of western Sichuan Province is similar to that of the Chinese Loess Plateau and of East Asia as a whole, suggesting that regional-scale fires depended mainly on changes in the intensity of the Asian summer monsoon. In addition, the fire regime of western Sichuan Province may have been influenced by the establishment of human settlement and agriculture in western Sicbuan Province and the southeastern Tibetan Plateau after about 5.5 cal ka BP, and by an intensification of cereal cultivation coupled with population expansion in southwestern China during the last two millennia.Wildfire is recognized as a critical Earth system process which affects the global carbon cycle, atmospheric chemistry, and ecosystem dynamics. Estimat- ing the potential impact of future climate change on the incidence of fire requires an understanding of the long-term interactions of fire, climate, vegetation, and human activity. Accordingly, we analyzed the black carbon content and the pollen stratigraphy of sediments spanning the past 12.8 ka from Lake Muge Co, an alpine lake in western Sichuan Province, in order to determine the main factors influen- cing regional fire regimes. The resuks demonstrate that wildfires occurred frequently and intensively during the late deglaciation and the early Holocene when the regional vegetation was dominated by deciduous forests. Wildfire occurrence decreased significantly during the Holocene climatic optimum between 9.2 and 5.6 cal ka BP. Overall, the wildfire history of western Sichuan Province is similar to that of the Chinese Loess Plateau and of East Asia as a whole, suggesting that regional-scale fires depended mainly on changes in the intensity of the Asian summer monsoon. In addition, the fire regime of western Sichuan Province may have been influenced by the establishment of human settlement and agriculture in western Sicbuan Province and the southeastern Tibetan Plateau after about 5.5 cal ka BP, and by an intensification of cereal cultivation coupled with population expansion in southwestern China during the last two millennia.

关 键 词：black carbon WILDFIRE summer monsoon human activity HOLOCENE Lake Muge Co 

分 类 号：X16[环境科学与工程—环境科学] S162[农业科学—农业气象学]