| This study is based on the annual rainfall and evapotranspiration,DEM,total runoff,and land cover from 2000 to 2019(1970,1980,1990,1995,2010,2015,2018 in 7 periods),Research on soil and vegetation coverage data has been carried out in the following aspects:(1)Constructing a research index system for ecological and hydrological zoning in Hengduan Mountain;(2)Spatial analysis of the main ecological and hydrological elements in Hengduan Mountain;(3)Analyzing the ecological and hydrological zoning The basic principle is to explore the ecological and hydrological zoning method suitable for the Hengduan Mountain area,and follow certain principles to divide the ecological and hydrological first-level and second-level ecological zoning in the Hengduan Mountain area.The research results are as follows:(1)Determining hydrological units through sub-river basin analysis,and on this basis,using Arc GIS spatial analysis method to obtain the spatial and temporal variation rules of main eco-hydrological elements in Hengduan Mountain region;(2)Principal component analysis was used to extract the main factors reflecting the climate characteristics,hydrological characteristics and ecological characteristics,and the ratio calculation method in the entropy value method was used to determine the weight of each index,so as to construct a complete index system;(3)According to the similarity and difference of underlying surface conditions in Hengduan Mountain region,677 subcatchment areas in Hengduan Mountain region were divided into two first-order ecohydrological types,namely the Yangtze River and the Southwest River,using the method of GIS and multivariate statistical analysis.(4)According to the evaluation results of ecohydrological elements,the study area was divided into six secondary ecohydrological types,and the spatial distribution characteristics of each ecohydrological type were analyzed.Among them,EHR1 includes Jialing River system,which is mainly grassland,arid and has little evapotranspiration.EHR2 is mainly located in the Mintuo River system,which is mainly forestland and relatively arid.EHR3 is located in the Jinsha River system,mainly grassland and woodland,with relatively drought and less evapotranspiration.EHR4: mainly cultivated land and woodland,with heavy rainfall intensity and wet;EHR5: It is mainly woodland and prone to heavy rain.It is humid all the year round and has high evapotranspiration,so it is easy to generate underground runoff.EHR6: Forestland is mainly humid with high evapotranspiration,and cultivated land is the main land use type.The control engineering measures according to local conditions are put forward.Partition results clearly underlying surface geological features reflect the hengduan mountainous areas and the management of land development and utilization,also reflects the hydrologic characteristics of distribution,to verify the accuracy and scientific rationality of the hydrological regionalization results,reflect the hydrological resources ecological similarities and differences in distribution system,It provides a scientific basis for the comprehensive development of water resources,disaster prevention and ecological environment control in the Hengduan Mountains region of China. |
