用VIC模型模拟黑河上游流域水分和能量通量的时空分布  

Spatial-temporal distribution of water and energy fluxes in the upper reaches of the Heihe River simulated with VIC model

作　　者：何思为[1] 南卓铜[1,2] 张凌[1] 余文君[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所,甘肃兰州730000 [2]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000

出　　处：《冰川冻土》2015年第1期211-225,共15页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金项目(41471059;91125006);冻土工程国家重点实验室开放基金项目(SKLFSE201009)资助

摘　　要：受地形起伏影响,山区流域的水分和能量通量时空分布差异很大.利用水文模型VIC(variable infiltration capacity)对黑河上游流域的水文和能量时空分布进行了模拟,并通过观测对模拟结果进行了验证.结果表明:VIC模型能够较合理地模拟研究区径流过程,对净辐射的计算也较准确,模拟得到的部分水分通量和能量通量(感热、潜热和土壤热通量)在趋势上较一致,但在数量上存在偏差.积雪过程对研究区的水文和能量循环有重要影响,VIC模型对积雪的模拟偏差较大,导致了每年4月左右的模拟径流偏低,也没有模拟出积雪融化导致的土壤含水量上升;同时,积雪模拟的不准确也明显影响到能量通量的模拟.在研究区,土壤水分变化受土壤冻融影响明显,VIC模型对气温较高、不发生冻融过程的7-9月土壤水分变化模拟较好,但是在其他月份,对积雪及表层土壤消融导致的土壤水分迅速增加和土壤冻结导致的土壤水分迅速减少两个过程的模拟比较差;VIC模型能够给出水分和能量各通量的时空分布,较好地揭示研究流域各个通量的空间异质性及相互影响.Due to the influences of complex mountainous topography,the spatial-temporal characteristics of water and energy fluxes in a mountainous river basin are often dramatically changed. In this paper,a macro scale hydrologic model,the variable infiltration capacity（ VIC） model,was used to simulate the spatial-temporal distribution of water and energy fluxes in the upper reaches of the Heihe River. The simulated results were validated with in-situ observations. It was showed that the VIC model is able to properly simulate the outlet discharge and net solar radiation,while it could only represent the changing trends of other variables,such as sensible heat flux,latent heat flux and ground heat flux. The simulated snowprocess differed from observations,leading to underestimation of outlet runoff,a sudden rise in soil moisture around April and a discrepancy in energy fluxes simulation. The VIC model has a good simulation of soil moisture in summer（ from June to September）,but bad in other months in which snowmelting and soil thawing / freezing processes occur. Snowmelting while top soil thawing will jointly induce a sudden rise in soil moisture,and top soil freezing will induce a fast drop in soil moisture. Overall,the VIC model is capable of simulating the spatial-temporal distribution of water and energy fluxes in mountainous basins with spaces to be improved where snowmelt and soil thawing /freezing take place.

关 键 词：水分通量 能量通量 VIC模型 时空分布 山区河流 黑河 

分 类 号：TV124[水利工程—水文学及水资源]