Effect of land use pattern on water quality in Liaohe Conservation Area

Using 2018 Landsat images and water quality data, Liaohe Conservation Area was divided into four study sections according to the urban areas of Tieling, Shenyang, Anshan and Panjin. The method of fuzzy comprehensive evaluation was used to evaluate the health status of river water quality in each section, then the Ecognition software was used to interpret remote sensing images, and finally the correlation between land use change and river water quality status in the four sections was analyzed. The results showed that Anshan Section had the largest agricultural land area proportion and the smallest water area proportion in different sections of Liaohe Conservation Area, while in Shenyang Section, the area proportion of woodland and grassland was the largest. In Liaohe Conservation Area, the health level of dissolved oxygen (DO) concentration was excellent, chemical oxygen demand (COD) was medium, total nitrogen (TN) concentration was ill, total phosphorus (TP) concentration was medium, ammonia nitrogen (NH₃-N) concentration was excellent in Shenyang Section and good in other sections. There was a good correlation between the proportion of land use types in Liaohe Conservation Area and river water quality indexes, among which the concentrations of NH₃-N, TP,TN and COD in river water were negatively correlated with the proportion of forest land and grassland, and positively correlated with the proportion of agricultural land and building land. DO concentration was positively correlated with the proportion of forestland and grassland, and negatively correlated with the proportion of agricultural land and building land.