天生桥一级入库径流变化趋势及归因分析OA

Due to the dual impacts of human activities and climate change,the inflow runoff of Tianshengqiao Cascade-I Reservoir has shown a significant decreasing trend in recent years compared to the initial operation period,posing numerous challenges to the optimal operation of the reservoir.This study employs a combined abrupt change detection method integrating cumulative anomaly analysis and Pettitt test,along with the separation evaluation method,to quantitatively identify the main influencing factors of inflow runoff.The results show that:① Watershed runoff mainly relies on precipitation recharge;since the 21st century,annual average precipitation has continued to decrease,leading to a simultaneous decline in surface water resources and reservoir inflow.②From 1936 to 2022,both annual average and flood season inflow discharges showed a significant decreasing trend,with annual decreasing rates of 2.27 m3/s and 4.11 m3/s,respectively.③Using 1956-1986 as the reference period,the contribution rates of climate change to inflow runoff changes were 71.05%and 89.43%for the periods 1987-2002 and 2003-2022,respectively,while those of human activities were 28.95%and 10.57%.This indicates that climate change remains the primary factor influencing interannual variations in inflow runoff,with a more pronounced impact in dry years.The research results can provide scientific support for watershed water resources management and joint reservoir operation.