River Watershed Non-point Source Pollution Control Planning

Heihe river basin is an important municipal water source for Xi' an city.In view of its relatively serious non-point source pollution, systematicalprogramming of basin non-point source pollution is conducted to protectits water quality. According to the idea that the purpose of basin non-pointpollution control and programming is to achieve coordinated developmentof economy, society and ecology, the total amount control idea of pointsource pollution treatment is applied to the study on non-point pollutioncontrol and programming. Various non-point pollution control measures,such as change of land use, construction of vegetable filter trips alongthe river, migration, and these combined are presented in this paper, andcorresponding non-point pollution load is also forecasted. In theoptimization of land use of the basin, environmental capacity of pollutantsincluding sediment, total phosphorus (TP) and total nitrogen (TN),cultivation land, grassland and abandoned land is taken as restrictedconditions, maximum economic income of the basin is taken as objectivefunction, multi-objective linear programming model is applied to optimizebasin non-point pollution control schemes. Based on the ecnomical analysisand evaluation of different control schemes, optimum non-point pollutionscheme is selected. Considering pollutant removal rate, pay back period,Benefit-Cost ratio, and economic benefit, four kinds of multi-objectivedecision formula are used to select optimum non-point pollution controlscheme.