Calculation and Analysis of Water Environmental Capacity of the Liaohe River Protection Area in Shenyang

To calculate the water environmental capacity of the Liaohe River protection area in Shenyang, provide scientific basis for the management of the protection area and similar rivers. According to the characteristics of North River, calculate the COD and NH3-N water environmental capacity of different water period by three control modes, such as the section head control, the section tail control, and the function tail control. According to the pollutant concentration response relationship between the mainstream and the branch, elicit the water environmental capacity of twelve branches. Results shows that the sort of capacity is wet season > normal season > dry season, section head control > section tail control > function tail control. Under the function tail control, the annual environmental capacity of COD is 57586.42 t/a, NH3-N is 5398.19 t/a. The conclusion are that the paper provide a scientific foundation for stable IV class water quality of the mainstream, support the management of total sewage and branches in Liaohe River protection area in Shenyang based on the environmental capacity.