近47年来降水变化和人类活动对滦河流域年径流量的影响

近47年来,随着流域降水量的减少,以及水利工程的修建、林草地的减少等土地利用方式的改变,在气候变化和人类活动双重因素的作用下,滦河流域年径流量呈现出显著的减少趋势。现基于降水-径流经验统计模型的构建,定量评估了滦河流域降水变化和人类活动对该地区年径流量的影响程度。结果表明:①1983年以前,滦河流域年径流量受环境变化影响较小,1983年以后,年径流量受到气候变化和人类活动影响较为显著;②1984年-2006年期间,受人类活动影响所产生的年均减水量为11.97亿m3,占该时段减水量的84.42%,受降水变化所产生的年均减水量为2.21亿m3,占该时段减水量的15.58%,人类活动的贡献率远大于降水变化。

Impacts of Precipitation Changes and Human Activities on Annual Runoff in the Luanhe River Basin during Recent 47 Years

In the recent 47 years,the annual runoff of the Luanhe River Basin has declined significantly caused by the natural climate change conditions such as the decreasing of the annual precipitation,and by the human activities such as the construction of hydraulic engineering facilities and the land use changes with the reduction of forest and grassland.In this paper,the impacts of precipitation variations and human activities on the annual runoff in the Luanhe River Basin were evaluated quantitatively based on the rainfall-runoff empirical statistical model.The results showed that:① The impacts of the environmental variations on the annual runoff were lower before 1983 than those after 1983;② During 1984 to 2006,the reduction of the average annual runoff was about 11.97×108 m3 caused by the human activities,which accounted for 84.42% of the total runoff reduction during this time period;whereas the reduction of the average annual runoff was about 2.21×108 m3 caused by the precipitation variations,which accounted for 15.58% of the total runoff reduction during this time period.Therefore,the impacts of human activities on the runoff reduction were much higher than those of precipitation variations.