Sedimentary flux of Lake Taibai, Hubei Province and correlations with precipitation and human activities in its catchment during the last century

Time-depth correlation of the sediment core from Lake Taibai,Hubei Province was established based on the ~(210)Pb intensity and CRS model.The sedimentary flux variation and its correlations with the summer precipitation and human activities during the last century in Lake Taibai catchment were discussed.There were six periods with high sedimentary flux.The former four periods,1900-1920,1928,1937-1942 and 1953-1954 AD,were cor- respondent with the four phases with a higher precipitation in summer,which were 1900-1920,1931,1938- 1939 and 1954 AD.The high sedimentary flux was resulted from more material input by stronger runoff.After three reservoirs were built in the upstream region of Lake Taibai inflow rivers in 1958-1963 AD,there was a lower aver- age sedimentary flux for Lake Taibai due to the regulation of the reservoirs to the flood and silts,and the controlling function of precipitation on sedimentary flux became weakened.The high sedimentary flux during 1958-1970 AD was mainly related to the land reclamation around the Lake,resulting lake area decreased.The high sedimentary flux during 1983-1993 AD was induced by the soil erosion with the rapid development of cultivation after the change of agricultural production patterns.By the contrastive analysis of sedimentary flux with precipitation and hu- man activities,the accuracy of the timescale of Lake Taibai sediment can be reliable,which also indicated the e- nough stable sedimentary environment.Thus,the sedimentary proxies can be used to reconstruct the environment evolution process in Lake Taibai catchment.