title: Lake sediment records on climate change and human activities in the Xingyun Lake catchment, SW China.
abstract: Sediments from Xinyun Lake in central Yunnan, southwest China, provide a record of environmental history since the Holocene. With the application of multi-proxy indicators (total organic carbon (TOC), total nitrogen (TN), δ13C and δ15N isotopes, C/N ratio, grain size, magnetic susceptibility (MS) and CaCO3 content), as well as accelerator mass spectrometry (AMS) 14C datings, four major climatic stages during the Holocene have been identified in Xingyun's catchment. A marked increase in lacustrine palaeoproductivity occurred from 11.06 to 9.98 cal. ka BP, which likely resulted from an enhanced Asian southwest monsoon and warm-humid climate. Between 9.98 and 5.93 cal. ka BP, a gradually increased lake level might have reached the optimum water depth, causing a marked decline in coverage by aquatic plants and lake productivity of the lake. This was caused by strong Asian southwest monsoon, and coincided with the global Holocene Optimum. During the period of 5.60-1.35 cal. ka BP, it resulted in a warm and dry climate at this stage, which is comparable to the aridification of India during the mid- and late Holocene. The intensifying human activity and land-use in the lake catchment since the early Tang Dynasty (∼1.35 cal. ka BP) were associated with the ancient Dian culture within Xingyun's catchment. The extensive deforestation and development of agriculture in the lake catchment caused heavy soil loss. Our study clearly shows that long-term human activities and land-use change have strongly impacted the evolution of the lake environment and therefore modulated the sediment records of the regional climate in central Yunnan for more than one thousand years.
authors.affiliation: Key Laboratory of the Plateau Surface Process and Environment Changes of Yunnan Province, Key Laboratory of Plateau Lake Ecology and Global Change, Yunnan Normal University, Kunming, China.
authors.forename: Wenxiang
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Key Laboratory of the Plateau Surface Process and Environment Changes of Yunnan Province, Key Laboratory of Plateau Lake Ecology and Global Change, Yunnan Normal University, Kunming, China.
authors.forename: Qingzhong
authors.initials: Q
authors.lastname: Ming
authors.affiliation: Key Laboratory of the Plateau Surface Process and Environment Changes of Yunnan Province, Key Laboratory of Plateau Lake Ecology and Global Change, Yunnan Normal University, Kunming, China.
authors.forename: Zhengtao
authors.initials: Z
authors.lastname: Shi
authors.affiliation: Key Laboratory of the Plateau Surface Process and Environment Changes of Yunnan Province, Key Laboratory of Plateau Lake Ecology and Global Change, Yunnan Normal University, Kunming, China.
authors.forename: Guangjie
authors.initials: G
authors.lastname: Chen
authors.affiliation: Key Laboratory of the Plateau Surface Process and Environment Changes of Yunnan Province, Key Laboratory of Plateau Lake Ecology and Global Change, Yunnan Normal University, Kunming, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Niu
authors.affiliation: Key Laboratory of Humid Subtropical Eco-geographical Process, Ministry of education, Fuzhou, China.
authors.forename: Guoliang
authors.initials: G
authors.lastname: Lei
authors.affiliation: Key Laboratory of the Plateau Surface Process and Environment Changes of Yunnan Province, Key Laboratory of Plateau Lake Ecology and Global Change, Yunnan Normal University, Kunming, China.
authors.forename: Fengqin
authors.initials: F
authors.lastname: Chang
authors.affiliation: Key Laboratory of the Plateau Surface Process and Environment Changes of Yunnan Province, Key Laboratory of Plateau Lake Ecology and Global Change, Yunnan Normal University, Kunming, China.
authors.forename: Hucai
authors.initials: H
authors.lastname: Zhang
mesh_terms: D002244:Carbon / Q000032:analysis / Q000737:chemistry; D002681:China; D002980:Climate; D057231:Climate Change; D004777:Environment; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000032:analysis / Q000737:chemistry*; D006802:Human Activities; D006801:Humans; D060106:Lakes / Q000032:analysis / Q000737:chemistry*; D009584:Nitrogen / Q000032:analysis / Q000737:chemistry
chemical_list: D002244:Carbon; D009584:Nitrogen