| In recent years, the environment effect on area dimension of Land Use/Land Cover Change (LUCC) is gradually taking seriously by the academic circles. One reason is the area difference of LUCC process is very big; the most important is ecological conservation to come true by changing land use. The estimating of LUCC area environment effects are more relationship to the country sustainable development strategy. As one of the environment effects, the effect of hydrological is the key territory of present research. For specially appointed area,analysis the driving force mechanism of LUCC, go deep into knowing the connection between land covered, climate ,hydrology change, already become the important means that policy analyses on area resource problem , environment problem and organism's habits problem.The paper object is a river basin of DaQinghe mountain area, by means of RS and GIS, according to the RS data information of 1987 year and 2000 year in DaQinghe mountain area, combining with the natural, society, economic statistics data build LUCC data base, analysis the characteristic of space-time development changes. Analysis the contribution rate of LUCC to the surface runoff based on the SWAT model, by setting up unlike scenes of LUCC, analysis the impact of the scene changes to the surface runoff and evaporation. And then probe the optimum LUCC pattern of DaQinghe mountain area, analysis simulating and forecast the element effect of LUCC to hydrology under the pattern, and then drawing the improvement suggestion of LUCC on DaQinghe mountain area. The results indicated that:From 1987 years to 2000 years, the cultivated land, grassplot, water area have equally falling off to varying degrees of DaQinghe mountain area river basin, cultivated area decreased12202 hm~2, Grassplot area decreased 16214 hm~2, Water area decreased 6038 hm~2; Forest land, construction land ,unused land are increased , forest land area increased 15337 hm~2 , construction land increased 19115 hm~2 , unused land increased 2 hm~2.LUCC of 2000 years compared with LUCC of 1987 years, the annual equal runoff cutting down 162 million m3, rate of change is 7.97%; the annual equal evaporation cuts down 38.95 mm, rate of change is 9.21% in the river basin. If the land is covered by forest land completely, annual equal runoff expects that for 1,802,000,000 m3, evaporations are 565 mm; if the land is covered by grass completely, annual equal runoff amounts are 1,459,000,000 m3, the evaporations are 207 mm.Above 25°slope field grain for green, the runoff decreased. The runoff cutting till 94.45% after turning into forestry, cutting till 92.85% after turning into grass; the evaporations increased after return the grain plots to forestry .the evaporations decreased after return the grain plots to grass, the forest evaporation increases till 102.68% , grass cuts then till 96.11%.In the area in which the slope degree is from 15 to 25 grain for green, the runoff decreased. The runoff cutting till 82.74% after turning into forestry, cutting till 73.21% after turning into grass; the evaporations increased after return the grain plots to forestry, decreased after return the grain plots to grass, the forest evaporation increases till 1119.19% , grass cuts then till 83.46%.Under the optimized LUCC pattern, the modulus of runoff comes down obviously; annual runoff changes between years tending to stability; Runoff assigns the modulus diminution , the runoff distributes tending to equation in a year; The self-restraint exponent rises , water of river is increased in low water crop. The evaporation is increased promptly, and then become stable later.As far as DaQinghe river basin, we should respond to different physical feature of a place, the general configuration of the earth's surface condition to designing different land used/ covered combination type, to solve the water resource shortage questions. From the angle that increasing the river basin's water yield to build the vegetation.
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