摘要
ANNUAL LAMINATIONS IN THE SEDIMENTS OF HONGFENG LAKE, CHINAANNUALLAMINATIONSINTHESEDIMENTSOFHONGFENGLAKE,CHINA¥WuFengchang;Wa...
Hongfeng Lake is an eutrophic freshwater atificial reservior.It began to restore water in 1960. Three sediment cores were taken from both about 25m of water in the center of Hongfeng bake in May 1991. The stratigraphy of the three cores was easily matched .by using prominent marking horizons and characteristic aqnences of laminations. In three layer Samples studied, diatom and other algae taxa appear in repeating apuences. The presence of laminations may reflect either the regular changes of physical-chemical conditions within the lake or the variation in the intensity of erosion and transport of material from the catchment, pat iculaly where instability in the lake-water system has occult as a result of human activities. The larninations were mainly cantal by seasonal variation of envionmental conditions,particularly climate.Unlike t of the previous examples, they have ben fo ̄ at most recent Sediments, in a small freshwater lake in the eastern slOPe of the QinghaiXiZang Plateau, China in a subtropical climate, which is adenly controlled by  ̄theastern and southwestern mon ̄n. It is believed that it's the first reported instanceOf laminated lake sediments from China.