Abstract:Using the Pearson correlation coefficient method, annual runoff and sediment were analyzed in order to find out the evolution characteristics and its impacting factors in the Lishui River during 1955-2009. The results showed that the annual runoff had no obvious change during this period, while the annual sediment transportation appeared significant decline trend, and had sudden change in the year of 1983. The relationship between precipitation, runoff and sediment transportation variation were analyzed, it turned out that human activities were the main reason causing the sediment transportation descent when the annual precipitation has no obvious change during 1955 to 2009. Thus, the sediment from the Lishui River to the Dongting Lake decreased by 4.59×106 t every year accordingly.