Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Chine → 2022 → Hydrological Process Simulation of Alpine and Arid Grassland Ecosystem Based on Improved SWAT Model ——A Case Study of the Upper Bayin River

Qinghai Normal University (2022)

Hydrological Process Simulation of Alpine and Arid Grassland Ecosystem Based on Improved SWAT Model ——A Case Study of the Upper Bayin River

傅笛

Titre : Hydrological Process Simulation of Alpine and Arid Grassland Ecosystem Based on Improved SWAT Model ——A Case Study of the Upper Bayin River

Auteur : 傅笛

Grade : Master 2022

Université : Qinghai Normal University

Résumé partiel
Grassland is the main land cover type and one of the most important ecosystem types in alpine and arid areas of China.Affected by climate,topography,human activities and other factors,grassland coverage has obvious spatial differences.Grassland with different coverage had different ability of interception and transpiration,which affected regional water cycle.However,the spatial variability of grassland vegetation coverage is seldom considered in the studies of eco-hydrological processes in alpine and arid inland river basins.Bayin River is a typical alpine and arid inland river basin and the fourth largest inland river in Qaidam Basin.The main types of land cover are grassland and wasteland.The spatial heterogeneity of grassland coverage is obvious in this watershed.Hydrological model is an effective means to reproduce and predict eco-hydrological processes at large regional scale.SWAT(Soil and Water Assessment Tool),a large-scale hydrological model with physical basis,has been widely used in the simulation of hydrological processes under different land use,climate and management measures and achieved good results.Leaf area index(LAI)is calculated in the plant growth module of SWAT model,which is used to represent vegetation growth status and vegetation coverage.However,this module only considers the impact of temperature while ignoring precipitation,terrain and human activities when calculating LAI.In addition,in areas lacking meteorological data,LAI calculated by SWAT model could hardly reflect its spatial heterogeneity.Compared with LAI calculated by eco-hydrological model,LAI based on remote sensing has the advantages of easy acquisition,wide coverage and spatial heterogeneity,and is more suitable for expressing vegetation coverage characteristics at regional scale.This study firstly established SWAT models based on CMORPHv1.0(Climate Prediction Center Morphing technique),CHIRPS V2.0(Climate Hazards Group Infrared Precipitation with Stations data),MSWEP V2(Multi-Source Weighted-Ensemble Precipitation)products and measured precipitation with altitude correction.in order to solve the problem of lack of meteorological data in the study area,and evaluated the runoff simulation effect corresponding to each precipitation data.On this basis,the optimal precipitation data suitable for the study area was selected.Secondly,based on GLASS(Global Land Surface Satellite)LAI and Landsat,ESTARFM(Enhanced Spatial and Temporal Adaptive Reflectance Fusion Mode)model was used to obtain LAI with high spatio-temporal resolution(1day/30m)that fit the spatio-temporal scale of SWAT model.And replaced the original LAI estimation module of SWAT model.Finally,the improved SWAT model was used to simulate the eco-hydrological process in the upper reaches of bayin River.The improved SWAT model was calibrated and validated using three kinds of river runoff,sediment content and high spatial and temporal resolution evapotranspiration data,and its simulation effect was compared with that of the original SWAT model.

Mots clés : LAI ;SWAT;Improvement ;Hydrological process ;Upper Bayin River ;

Présentation (CNKI)

Page publiée le 30 octobre 2022