| In recent years, the Tuwei Watershed national economy realized the swift growth. The agricultural economy realized full scale development, and the industrial production made great progress by leaps and bounds. Tuwei River supporting the basin economic development took an important place of water resource, and its function and status were prominent day by day. Therefore, carrying out the research on the distributional hydrology model of Tuwei Watershed and establishing the suitable the hydrology model, is helpful to understand the local hydrology water resources condition, forecast hydrology physical process and use water resources reasonablely, which have the important theory and practical significanc for the solution of related ecological question and economic problem.This article chose the distributional hydrology model SWAT through GIS, considered fully the factor's space and time distributions of local climate, terrain, landuse, soil and so on, established the spatial databases, the meteorological database, the landuse database, the soil attribute database in Tuwei Watershed. This article analysised terrain through the digital elevation chart DEM, extracted basin digital river system, discretized the watershed , and finally determined the sub-watershed and the hydrology response unit division level.This article analysed parameter sensitivity of the SWAT model , calibrated parameter through Gao Jiachuan hydrologic station actual runoff material from 1977 to 1984,validated parameter through actual runoff material from 1984 to 1989,and during both indication time and calibration time the result showed that: the simulation error of actual runoff simulation is very small, the correlation coefficient is above 0.8, the model efficiency coefficient is above 0.7; the simulation error of monthly runoff simulation is also very small, the correlation coefficient is above 0.75, the model efficiency coefficient is about 0.65.The SWAT model's exploiter believed that the expected value of the model is about 0.6,which indicated that the model expressed the research area parameter accurately, and described research area hydrology process, therefore, the SWAT model is suitable for the Tuwei watershed.Based on the above result, this article has established 5 different landuse scene and 24 kinds of hypothesis climate scene. The simulation result indicated that along with the forest and grass covering's rate increase, the Tuwei watershed runoff assumes the reduction tendency, so the forest and grass has certain function to regulation and storage of runoff; The influence of forest land covering rate is bigger than grass obviously to the amount of runoff. Under the future scene, if Tuwei watershed has the ecological damage, when people carries on the repairment, the afforestation is better to self-control moisture and discrease runoff than planting grass; in 24 kinds of hypothesis climate scene, S 21 is making the amount of runoff increase most combination scenes, namely P increases 20%, T reduces by 2℃,which is increased the most advantageous combination scene to the Tuwei River basin runoff; The one who causes the amount of runoff to reduce most is the scene S 5, namely P reduces 20%, T increases by 2℃, which is the most disadvantageous combination scene to the Tuwei watershed amount of runoff. |
