Recent Environmental Change Inferred from Grain-Size Records in
详细信息
- 责任者：Wang Xiaolei (College of Geography Science ; Nanjing Normal University ; Nanjing 210046 ; China) ; Yang Hao
- 刊名：Acta Sedimentologica Sinica
- 出版年：2010
- 卷期：28(4)
- 关键词：湖泊沉积物 ; lake sediments ; 粒度分析 ; grain-size analysis ; 现代沉积 ; recent deposit ; 云南 ; Yunnan Province
- 页码：p.776-782
- 图表：3 illus., 28 refs.
- 分类号：1400
- issnNo：ISSN1000-0550
- isbnNo：CN62-1038/P
摘要
210Pb and 137Cs were used to analyze for the Fuxian Lake sediment core. 210Pb dating result showed a little deviation from 137Cs dating, and two reasons were investigated. According to the feature of Fuxian Lake, the authors analyzed the grain size characteristics and obtained the content of the core, which contained 36% of clay, 44% of fine sand and 18% of coarse sand. By calculation, the different grain-size parameters were also obtained, the mean grain diameter was between 6.48 and 7.92, the standard deviationwas between 1.27 and 1.42, and the skewness was between -0.18 and 0.04. Based on radionuclide dating and grain-size distribution characteristics in the sediment core, the authors concluded a sedimentary environment in Fuxian Lake had been greatly changed since 1878, which can be marked off four stages: natural evolution stage, man-made disturbances stage, man-made transformation stage, and recent treatment stage. Human activities of historical period had played a very important role in changing the environment of Fuxian Lake.