Research On Distributed Hydrological Model In Mountainous Region-based On GIS And RS

Distributed Hydrologic Model is an important instrument to study hydrologic pattern and solve practical hydrologic problems. It is based grid or sub-watershed, which requires many process parameters and datas fully reflecting the hydrologic heterogeneity of the watershed space.T'echnologies like geographic information system and remote sensing can provide information coving the whole earth, elevation information and information of radiation of every wave brand…, with which, datas of large-scale, high density of time and space like ground surface temperature, vegetation index, snow covering, evaporation could be inversed. Low cost is anadvanatage when comparing the information from GIS, RS with tradition methods, and the information captured are average information on the surface are captured, which fits to the input requirement of distributed hydrologic model. In this dissertation, the author tries to explore other source of information like GIS,RS to build distributed hydrologic model.This article is based on the data of DEM provided by USGS, by usage of the function of geographic information system space analysis, can not only obtain landform parameters like the distribution of elevation, slop and aspect, but also can extract drainage, watershed divide,watershed boundary.When building traditional hydrilogical model, information of rainfall, temperature and evaporation from single hydrilogical station and telemetry station is used to replace average rainfall, temperature and evaporation, which heavily relied on the distribution of stations and may be deviated with the reality in some areas where rainfall, temperature and evaporation are obviously affected by land from, like montainous area. In this article, based on watershed landform information and drainage system information obtained, supported by GIS method, comparing different geo-statistics and the rainfall interpolation results based on geo-statistics of different models, the author tries to procue grid rainfall information,isohyet line information and surface average rainfall information which are more truthful. The characterisic of remote sensing techonolgy and the principle of evaporation, take advantage of MODIS remote information calculation to obtain Grid land surface temperature information,NDVI,snow coverage information, and conduct analysis on the reliability of related land surface temperature data and the relationship between air temperature and land surface temperature. Build SEABAL model based on the pincriple of ground surface energe balance and conduct research on the inversion of evaporation information in the area studied, obtained grid evaporation information with more physics meaning, and meanwhile conduct preliminary research on the parameter sensitivity of SEBAL model.At last, based on above distributed watershed information of underlying surface,rainfall,temperature,evaporaton,snow coverage, etc, on the foundation of snow-melt three component Xin'anjiang Model, build a Mountainous distributed snow-melt runoff model. reflecting the watershed characteristics of western Tianshan Mountain. The Result shows that this distributed model can achieve satisfactory forecast accuracy.The main contribution of this article is to compare interpolations of different geo-statistics methods and different models, identify comparatively suitable method and model of interpolation. Analyze the relativity between land surface temperature information obtained by inversion based on remote sensing and temperature information obtained by traditional method, thus deduct temperature distributed information through land surface temperature distributed information. Build SEBAL model supported by RS and MODIS data, which can be adapted to western Tianshan mountainous area, obtain distributed information of evaporation by inversion in researched area and analyze the parameters'sensitivity of SEBAL model when applied in mountainous area, examine the reliability of the distributed information of evaporation obtained. All of these provide a set of method of obtaining distributed input information to build distributed hydrographic model for district that lacks of information like mountainous areas.