Characteristic Analysis of Ecological Water Use in Xilin River Basin Based on Remote Sensing

Abstract

Our study area is the Xilin River basin. Remote sensing approach was used to retrieve ecological water use by using MODIS images from Apr. to Sept. of 2000、2007、2010–2014, and using auxiliary environmental data from the same time periods. The results showed the spatial distribution of ecological water use was consistent with the land surface condition. The ecological water use had the trend of strip reduction from the upstream to the middle and lower reaches. The annual variation was extremely related to the precipitation. Large amount of precipitation in the year, ecological water use was larger, and vice versa. The areas with higher ecological water use were forest land and farmland, followed by unutilized land. Grassland and construction land were lower. The order of ecological water use of different land use type was basically: forest land> farmland>unutilized land>construction land>grassland. In the year of abundant water, the time of the maximum value of ecological water use appeared in June-July with the time of precipitation. In dry year, the time of the maximum value had no rule. The single factor correlation analysis of the monthly ecological water use and monthly meteorological factors showed that the most relevant meteorological factor is precipitation. The correlation coefficient is 0.776.