Research Of Water Resources Changes In Wulungur River Catchment Area Based On SWAT Model

In our country, water is increasingly becoming scarcity resources,especially in the northwest regionwhere broad is vast while population is rare, the total amount of water per capita in that place is less, andthe available water resources is even less.In wulungu river basin,the economic growth,the industry and theagriculture has developed rapidly in recent years. As the important water source along the coast,thewulungu river supports the basin’s economic development,and it plays an indispensable role in the studyarea.This paper applied the SWAT model on the GIS platform.First of all,this paper collected basic data inthe study area, and built spatial database and attribute database of the wulungu river basin;and then on thebasis of above, built the distributed hydrological SWAT model of wulungu river basin,which could be usedto simulate the runoff change,and by using ertai hydrological station runoff data from2000to2009,thispaper conducted parameter calibration and model validation;finally, this paper setted up the changingscenarios of climate and land use,and simulated to analysis the features of changing in runoff that underdifferent climate and land use scenarios.The following aspects are mainly included in this paper:(1) Firstly,this paper analyzed and processed the basic data which was including land use, soil andmeteorological and hydrological data, established the corresponding database, divided sub-basin,generatedriver network, determined basin boundaries,divided hydrological response units,and extracted thehydrological parameters in ArcGIS9.3platform using ArcSWAT2.3.4. The entire study area was dividedinto44subbasins and249hydrological response units.(2) Secondly,this paper built the distributed SWAT monthly runoff model, simulated runoff usingexisting basic data,and adopted monthly runoff data measured by ertai hydrological station for calibrationand validation of the model. The efficiency coefficient of the calibration period2000-2005was0.67, theaverage relative error was6.56%, and the linear correlation coefficient was0.70; the efficiency coefficientof validation period2006-2009was0.80, the average relative error was11.58%, and the linear correlationcoefficient was0.81.The result above showed that applicability of the model in wulungu river was better.(3) Thirdly,this paper studied the climate change’s impact on wulungu river basin runoff by assumingvarious climate change scenarios in the future.The results showed that when the basin temperatures rised1℃, the precipitation was constant,and runoff decreased by1.60%, the runoff was negativelyrelated withthe temperature; when rainfall increased by10%, the temperature was constant, and runoff increased by4.21%, the rainfall was positively related with the runoff,and the influence of rainfall on runoff was greaterthan that of temperature on runoff,the result also showed that the mainly influence factor in wulungu riverbasin’s future climate was rainfall,and the second was the temperature.(4) Finally,this paper setted up three kinds of land use change scenarios, and explored the response ofwulungu river basin runoff under the land use changing.The study result shows that from1986to2010landuse changing led to changes in runoff rate was16.24%,and its impact on surface runoff was larger,the mainreason was that the runoff watershed land use and development led to changes in the characteristics of theunderlying surface.