祁连山黑河径流变化特征及影响因素研究

Runoff variation characteristics and influencing factors in the Heihe River Basin in the Qilian Mountains

基于黑河流域径流、气象和土地利用类型等资料,采用弹性系数等方法研究了黑河径流变化特征及影响因素。结果表明:(1)1990年后黑河流域径流量增加趋势明显加速,并且在黑河干流表现最为明显,1957—1990年莺落峡站径流量增加速率为0.75×10^(8) m^(3)·(10a)^(-1),而1991—2020年其增加速率为2.60×10^(8) m^(3)·(10a)^(-1),后者是前者的3.47倍,并且黑河全流域1990年后径流量增加主要发生在夏季和秋季,较1990年前分别增加了7.07%和26.58%。(2)径流对气候变化的响应在夏季最为敏感,并且降水是导致径流增多的主要气候因素,夏季降水量增多1.000%,同期径流量平均增多0.741%(P<0.01)。(3)2020年较1980年黑河流域耕地和建设用地面积相对增幅分别为24.20%和71.43%;草地和未利用土地面积相对降幅分别为1.30%和5.28%。径流量与林地面积、建设用地面积呈正相关,而径流量与草地面积呈负相关。研究结果可以为黑河流域水资源的科学管理、优化配置和后续生态工程的实施提供参考。

Based on the data of runoff,meteorology,and types of land use,the characteristics of and contributors to runoff changes in the Heihe River of China were studied using elasticity coefficients and other methods.(1)The results show a trend of increasing runoff,with significant acceleration after 1990 and which was most obvious in the Heihe River,specifically at Yingluoxia station.Here the rate of increase in runoff from 1957 to 1990 was 0.75×10^(8) m^(3)·(10a)^(-1),whereas the rate of increase from 1991 to 2020 was 2.60×10^(8) m^(3)·(10a)^(-1),the latter being 3.47 times higher than the former.This increase in runoff mainly occurred in summer and autumn,with increases of 7.07%and 26.58%,respectively,compared with the pre-1990 period in the Heihe River Basin.(2)The effects of climate change on runoff were most acute in summer,with precipitation being the main climatic factor contributing to increased runoff.A 1.000%increase in summer precipitation was associated with a 0.741%average increase in runoff over the same period(P<0.01).(3)The relative increases in arable land and construction land area in 2020 compared with 1980 in the Heihe River Basin were 24.20%and 71.43%,respectively;the relative decreases in grassland and unused land area were 1.30%and 5.28%,respectively.The area of forested land,area of construction land,and runoff are positively correlated,whereas the area of grassland is negatively correlated with runoff.The results of this study can provide a reference for the rational allocation,scientific management,and subsequent implementation of ecological projects in the Heihe River Basin.