基于SWAT模型的细河流域土地利用/覆被变化对径流影响的研究

摘要

Land use and land cover change play an important role in hydrological process of Xihe basin .In order to analyze the hydrol-ogy effect caused by land use and land cover change , this paper constructs the SWAT model applied to Xihe basin and calculates the mean monthly runoff , annual mean surface runoff depth , mean annual evaporation and mean annual soil side flow .The results showed:mean monthly runoff increased 8.40% under the situation of farming and forestry land areas are increasing; Mean monthly runoff decreased 4.11%under the situation of construction land areas are increasing; Mean monthly runoff decreased 1.93% under the situation of dry land and other unused land areas are increasing .To sum up, the change of farming and forestry land in Xihe basin provoked the relatively greatest impact on runoff volume , and increase of farming and forestry land areas made the runoff increase;The change of dry land and other unused land provoked the relatively smallest impact on runoff volume , and increase of construction land and dry land and other unused land areas made the runoff decrease .%土地利用/覆被变化对细河流域的水文过程影响显著.为研究不同土地利用/覆被情景对流域水文要素的影响情况,本文构建了适用于细河流域的SWAT分布式水文模型,并拟算出不同情景下的流域多年平均月径流量、多年平均地表径流深度、多年平均蒸发量以及多年平均土壤侧流.模拟结果显示:当流域农林用地增加时,平均月径流量增加了8.40%;当建设用地增加时,平均月径流量减少了4.11%;当旱地及其他未利用地增加时,平均月径流量减少了1.93%.综上所述,细河流域农林用地变化对径流产量的影响相对最大,其增加导致径流量增加;旱地及其他未利用对径流产量的影响相对最小,建设用地和旱地及其他未利用地的增加导致径流量减少.