流域土地利用变化对洪水径流过程的影响

Effect of river basin land use change on flood runoff process

大清河水系土地利用发生了较大变化,并对洪水径流过程产生了影响。选择大清河水系紫荆关流域为研究对象,在对土地利用类型分类的基础上,采用1988年和1996年两期土地利用图分析了土地利用变化情况,除林地和灌木林面积减少外,其他土地利用类型面积增加。利用1984-1996年实测降雨径流资料对SWAT模型进行了率定和验证,并对两期土地利用情况进行了径流模拟,结果表明,土地利用变化使紫荆关流域的年径流减少。

The land use has changed in Daqing River Basin and this change influenced flood runoff. To study this problem, Zijingguan sub-catchment of Daqing River Basin was selected, where the land use types were categorized, and the change of each land use type was analyzed by using land use data in 1988 and 1996. The forest land area decreased and the land area of other types increased. The SWAT model is calibrated and verified by the observed data during 1984 - 1996, and the runoff was modelled under the land use condition in 1984 and 1996. The results show that land use change in Zijingguan sub-catchment leads to runoff decrease.