CMADS驱动SWAT模型在水循环模拟中的应用--以洱海流域为例

Application of SWAT model driven by CMADS in water cycle simulation of Erhai Basin,Yunnan Province

基于大气数据驱动水文模型的输出结果开展水循环模拟研究是大气和水文学界的研究热点。利用中国大气同化驱动数据集CMADS驱动SWAT模型,模拟2009~2016年期间洱海流域关键水循环要素的时空分布特征。结果表明:①CMADS数据集可很好地驱动SWAT模型,在洱海流域适用性较好,可用于水循环模拟研究。②从时间上看,洱海流域年降水量、实际蒸散和年产水量均呈现出先减少后增加的趋势,分别以4.6,29.3,15.0 mm/a的速率递增,多年平均降水量、多年平均实际蒸散发和多年平均产水量分别为792.8,565.5,286.1 mm。从空间上看,洱海西部降水最丰沛,东部地区次之,北部地区最低;实际蒸散发空间差异性相对较小,高值区主要分布于洱海湖区周围;产水量空间分布差异性较大,洱海西部产水量最大,其次为洱海北部和东部山区。③湿润度呈现出增加的趋势,而产水系数表现出减少的趋势,多年平均湿润度和产水系数分别为0.61和0.43;实际蒸散发与降水变化趋势一致,但与潜在蒸散发变化趋势相反,表明水分条件是限制洱海流域潜热的主要因子。

The simulation of water cycle based on the output of hydrological model driven by atmospheric data is a research hotspot in the field of atmosphere and hydrology.Using CMADS-driven SWAT model,the spatial and temporal distribution characteristics of key water cycle elements in Erhai basin during 2009-2016 were simulated.The results show that(1)CMADS data set can drive SWAT model well,and it has good applicability in Erhai basin,and can be used for water cycle simulation.(2)In terms of time,annual precipitation,actual evapotranspiration and annual water production in Erhai River Basin showed a first decreasing and then increasing trend,with increasing rates of 4.6 mm/year,29.3 mm/year and 15 mm/year,respectively.The annual average precipitation,annual actual evapotranspiration and annual average water production were 792.8 mm,565.5 mm and 286.1 mm,respectively.Spatially,the precipitation in the western part of Erhai Lake is the most abundant,followed by the eastern part and the lowest in the northern part.The spatial difference of actual evapotranspiration was relatively small,and the high value area mainly distributed around the Erhai Lake area.The spatial distribution of precipitation was quite different.The largest precipitation was in the western part of Erhai Lake,followed by the northern and eastern mountainous areas.(3)The moisture index showed an increasing trend,while the water production coefficient showed a decreasing trend.The average annual moisture index and water production coefficient were 0.61 and 0.43,respectively.The actual evapotranspiration was consistent with the precipitation trend,but contrary to the potential evapotranspiration trend,indicating that the water condition was the main factor limiting latent heat in Erhai Basin.