Abstract:

In recent years, the problem of agricultural non-point source pollution in the Aihe River Basin has become prominent, and its water environment quality directly affects the drinking water safety of the downstream Dandong City. In this paper, the improved export coefficient model (IECM) was used to study the non-point source pollution status of the Aihe River Basin, and the nitrogen and phosphorus pollutant load of the Aihe River Basin was calculated. The results showed that in the output load of total nitrogen and total phosphorus of non-point source pollutants, planting sources contributed 62.2 % of total nitrogen and 51.5 % of total phosphorus, livestock and poultry breeding contributed 23.5 % of total nitrogen and 34.4 % of total phosphorus, and rural living sources contributed 14.3 % of total nitrogen and 14.1 % of total phosphorus. The research revealed that the pollution source of planting industry was an important source of pollution load, accounting for 61.2%. Livestock and poultry breeding was also an important source of pollution, accounting for 24.5 %. The contribution of rural life sources was relatively small, accounting for 14.3 %. Overall, the contribution rate of planting industry to river non-point source pollution was the largest, and the overall emission of nitrogen and phosphorus pollutants had been increasing year by year. This paper studies the pollution status and formation mechanism of non-point source pollution in Aihe River Basin and puts forward measures, in order to lay a theoretical foundation for the precise implementation of non-point source pollution control in Aihe River Basin.

Key words: Aihe River Basin, non-point source pollution, agricultural non-point source pollution, Fengcheng City, export coefficient method, rural domestic pollution, planting industry pollution, livestock and poultry farming pollution