气候变化和人类活动对石羊河上游径流的影响

Based on the hydrological and meteorological data from 1960 to 2009 in the upper reaches of Shiyang River basin. using slide t detected method , accumulative anomaly and multi-regression methods,this paper analyzed the long-term trends of the runoff and climate in this region, and explored the contributive ratio affecting runoff by human activities. The results show that :(1)The temperature had a significant increasing trend and the tendency of precipitation punily ascends during the past 50 years,while the potential evaporation increased significantly in the upper reaches of Shiyang River basin.(2) The annual runoff variation tendency overall descends slowly,after 1975,the annual runoff frequently fluctuated.(3) The runoff variation is influenced by the climate changes and human activities, climate variations accounted for 44% of decrease in streamflow during 1975 to 2009, while human activities accounted for 56%.Therefore, human activities played a dominant influence inthe decline of the streamflow in the upper reaches of the Shiyang River.n this paper.