寒区森林流域产水量时空变化规律研究——以永翠河流域为例

Study on Spatial and Temporal Variation Laws of Water Yield in Forest Basin of Cold Region——Taking Yongcui River Basin as an Example

为探究寒区森林流域产水量时空变化规律,研究以永翠河流域为研究区域,基于1994—2015年总计22年的实测径流数据构建SWAT模型,分析流域内产水量时空变化特征,探究气象要素及土地利用变化对产水量的影响。结果显示:①1994—2015年,永翠河流域产水量年际波动较为明显,总体呈现上升趋势,年内产水量总体呈现先增后减的单峰型分布;②永翠河流域产水量空间分布总体呈东、西部高,中部低的分布格局,各土地利用类型中落叶林产水量最多,常绿林产水能力最强;③永翠河流域落叶林面积占比最大,森林覆盖面积达到95%以上,土地利用类型年际变化不明显,对产水量影响不显著;④永翠河流域降水、潜在蒸散发及实际蒸散发均呈现不同程度的下降趋势,其中降水是产水量主要影响因素。研究结果能够为寒区森林流域水资源优化配置及生态保护提供参考。

In order to study the spatial and temporal variation laws of water yield in the forest basin of the cold region,a SWAT model was established based on the total measured runoff data of 22 years from 1994 to 2015 in Yongcui River Basin.The spatial and temporal characteristics of water yield in the basin were analyzed,and the effects of meteorological factors and land use changes on water yield were discussed.The results show that:①from 1994 to 2015,the interannual water yield in Yongcui River Basin fluctuates obviously,showing an upward trend.The annual water yield shows a unimodal distribution of increasing first and then decreasing;②the spatial distribution of water yield in Yongcui River Basin is generally high in the east and west but low in the middle.Among all land use types,the deciduous forest has the highest water yield,and the evergreen forest has the strongest water-yielding capacity;③the area of the deciduous forest is the largest in Yongcui River Basin,and the area of forest cover is over 95%.The interannual change of land use types is not obvious,and its influence on water yield is not significant;④the precipitation,potential evapotranspiration,and actual evapotranspiration in Yongcui River Basin show a decreasing trend in different degrees,and precipitation is the main factor influencing water yield.The results can provide a reference for the optimal allocation of water resources and ecological protection in the forest basin of the cold region.