近现代高邮湖沉积记录的环境变化

1 Introduction Gaoyou Lake is the third largest lake in Jiangsu Province. It lies in central Jiangsu Province, lower reaches of the Huaihe River, and west of the Jing–Hang (Beijing–Hangzhou) Grand Canal. Previous research on environmental changes of the…

Environmental changes during modern period from the record of Gaoyou Lake sediments,Jiangsu

Based on analysis of parameters of cores taken from Gaoyou Lake, including magnetic susceptibility, grain-size characteristics and sedimentary rate, environmental changes during the modern period were examined with the assistance of historical records and Gaoyou Lake water level materials. It is concluded that during the modern period a higher value of magnetic susceptibility and a lower sediment grain size coincided with a wet climate,while a lower value of magnetic susceptibility and a higher grain size were related with a dry climate. The results indicate that the climate in the 123 years period from 1880 to 2003AD can be divided into four stages: two low water level stages (1880-1915AD, 1948-1981AD) and two high water level stages (1915-1948AD, 1981-2003AD). It appears that the regional climate generally underwent a dry-wet-dry-wet pattern in 30-year cycles. At present, it is at the end of a wet period, so the regional climate is expected to become dry in the near future. This conclusion corresponds with the climate records in the historical literature of the Gaoyou area,and it also matches with the climatic changes in North Jiangsu area.