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Two parallel sediment cores (30cm long) were extracted from Lake Sayram, in the Tianshan Mountains of Xinjiang in arid northwest China. We used Pb-210 and Cs-137 dating, multi-proxy indices, including geochemical composition, carbonate content, magnetic susceptibility (MS), and delta C-13 and delta O-18 of bulk carbonate, to reconstruct regional environmental change over the past two centuries. High evaporation modifies delta O-18 and delta C-13 of the dissolved inorganic carbon in lake water and may be responsible for the covariance between delta C-13 and delta O-18 of bulk carbonate. The ratio of immobile to mobile elements (CI=(Fe+Al+Mn+Cr+Co+Ni)/(K+Na+Ca+Mg+Sr+Ba)) is associated with humidity, and the ratio of Sr/Ca reflects lake salinity. Constrained cluster analysis of the multi-proxy indices was used to partition sediment deposition into three periods. In the first period of 1820-1890s, the climate was dryer with high evaporation, and lake water had higher salinity. During the second period from 1890s to 1960s, multi-proxy indices suggested that regional humidity increased and there was relatively more chemical weathering. The latest period, 1960s to present day, was the wettest of the past nearly 200 years. Nevertheless, we infer that human-related impacts have greatly increased in the last 50 years from the increased MS and phosphorus content.