南水北调与水利科技（中英文）2025，Vol.23Issue(4)：820-829,10.DOI:10.13476/j.cnki.nsbdqk.2025.0083
尼洋河上游流域径流变化特征与归因
Characteristics and attribution of runoff changes in the upstream of Niyang River basin
摘要
Abstract
Considered one of the most pressing global environmental issues,climate change has been extensively studied by scholars regarding its combined impact with human activities on runoff variation.In watersheds less affected by human activities,climate change and vegetation change are the two main driving factors for runoff changes.However,the contribution of climate change and vegetation change to runoff change was quite different for different basins.In light of this,the upper reaches of the Niyang River basin were selected as the study area to quantitatively analyze the impacts of climate change and vegetation change on runoff,providing theoretical basis and technical support for the planning,management and sustainable utilization of water resources in the basin. The Pettitt method was used to detect the change point of the leaf area index(ILA)sequence in the upper reaches of the Niyang River basin from the year 1981 to 2017.MATLAB was used to extract the ILA value of each grid within the basin,and the average value of the grid was taken as the average ILA of the basin,which was used to divide the reference period and change period.The Mann-Kendall rank correlation test was used to assess the trends of annual rainfall,annual evapotranspiration,annual ILA and annual runoff for the period 1981-1998,2000-2010 and 1981-2010,respectively.Changes of annual average rainfall,evapotranspiration,ILA and runoff depth before and after the change point were analyzed.The Xin'anjiang-ET model based on remote sensing ILA was constructed.First,the ILA was used to estimate the surface conductance,followed by the parameters of Penman-Monteith model.Finally,the land surface evapotranspiration was calculated,and the parameters were automatically optimized by particle swarm optimization. A change point was detected in the annual ILA series of the upper Niyang River basin in 1999 at the 0.01 significance level,indicating a significant shift in the vegetation coverage in the basin before and after 1999.Examining the changes of land use types in the basin,the grassland area in the upper reaches of the Niyang River basin increased by 6％after the change point(after 2000)compared with that before the change point(before 1999);The area of forest land and unused land decreased by 4％.The Mann-Kendall rank correlation test showed no change in rainfall before and after the change point;The annual average evapotranspiration of the basin decreased by 97 mm,and the annual average ILA increased by 0.06;The annual average runoff depth increased by 63 mm.The Xin'anjiang-ET model was effectively applied to the runoff simulation of the basin,and the Nash-Sutcliffe efficiency coefficients of 0.81 and 0.88 for the calibration and validation periods respectively.The results indicated that under the influence of climate change,the variation of runoff was only 2 mm,accounting for 3.2％of the runoff rheology.In contrast,the impact of vegetation change was more significant.The reduction of forest area and the increase of grassland area made the runoff in the change period increase by 61 mm compared with the baseline period,accounting for 96.8％of the runoff. The rationality of estimating vegetation change impacts on runoff variation was effectively improved by the Xin'anjiang-ET model.It could be concluded that the main factor leading to runoff changes in the upper reaches of the Niyang River basin was the change of vegetation cover.关键词
植被变化/气候变化/径流/遥感/叶面积指数/模型Key words
vegetation changes/climate change/runoff/remote sense/leaf area index/model分类
建筑与水利引用本文复制引用
马煜斐,姜亦泓,王富强,吕素冰,刘艳丽..尼洋河上游流域径流变化特征与归因[J].南水北调与水利科技（中英文）,2025,23(4):820-829,10.基金项目
国家自然科学基金项目(U2443203 （）
52279014) （）
农业重大科技专项项目(NK202319020506) （NK202319020506）
