Quantifying effects of conservation practices on non-point source pollution in the Miyun Reservoir Watershed, China

• Published in: Environmental monitoring and assessment Vol. 191; no. 9; p. 582
• Main Authors: Qiu, Jiali, Shen, Zhenyao, Chen, Lei, Hou, Xiaoshu
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.09.2019; Springer Nature B.V
• Subjects: Agricultural land; Agricultural practices; Agriculture - methods; Artificial wetlands; Atmospheric Protection/Air Quality Control/Air Pollution; Barren lands; Basins; Beijing; Best management practices; China; Conservation; Conservation of Water Resources; Conservation practices; Conservation tillage; Contour farming; Design parameters; Detention basins; Drinking water; Earth and Environmental Science; Ecology; Ecosystem; Ecosystem degradation; Ecotoxicology; Environment; Environmental Management; Environmental Monitoring; Environmental science; Eutrophication; Fertilizer application; Fertilizers; Forest management; Forests; Grassed waterways; Hydrologic models; Land pollution; Land use; Loads (forces); Manure; Mineral nutrients; Monitoring/Environmental Analysis; Nitrogen - analysis; Non-Point Source Pollution - analysis; Non-Point Source Pollution - statistics & numerical data; Nonpoint source pollution; Phosphorus; Phosphorus - analysis; Point source pollution; Pollutant load; Pollutants; Pollution; Pollution control; Pollution load; Precipitation; Quality control; Reservoirs; Soil; Soil conservation; Soil erosion; Soil management; Soil nutrients; Soil pollution; Soil properties; Soil types; Soil water; Soils; Spatial distribution; Stress concentration; Strip cropping; Temporal distribution; Tillage; Wastewater; Wastewater discharges; Water pollution; Water Quality; Watershed management; Watersheds; Waterways; Wetlands; Beijing; China; SWAT; Temporal distribution; Best management practice; Non-point source pollution; Miyun Reservoir Watershed; Spatial distribution
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-019-7747-y

Non-point source (NPS) pollution, including fertilizer and manure application, sediment erosion, and haphazard discharge of wastewater, has led to a wide range of water pollution problems in the Miyun Reservoir, the most important drinking water source in Beijing. In this study, the Soil and Water Assessment Tool (SWAT) model was used to evaluate NPS pollution loads and the effectiveness of best management practices (BMPs) in the two subwatersheds within the Miyun Reservoir Watershed (MRW). Spatial distributions of soil types and land uses, and changes in precipitation and fertilizer application, were analysed to elucidate the distribution of pollution in this watershed from 1990 to 2010. The results demonstrated that the nutrient losses were significantly affected by soil properties and higher in both agricultural land and barren land. The temporal distribution of pollutant loads was consistent with that of precipitation. Soil erosion and nutrient losses would increase risks of water eutrophication and ecosystem degradation in the Miyun Reservoir. The well-calibrated SWAT model was used to assess the effects of several Best Management Practices (BMPs), including filter strips, grassed waterways, constructed wetlands, detention basins, converting farmland to forest, soil nutrient management, conservation tillage, contour farming, and strip cropping. The removal rates of those BMPs ranged from 1.03 to 38.40% and from 1.36 to 39.34% for total nitrogen (TN) and total phosphorus (TP) loads, respectively. The efficiency of BMPs was dependent on design parameters and local factors and varied in different sub-basins. This study revealed that no single BMP could achieve the water quality improvement targets and highlighted the importance of optimal configuration of BMP combinations at sub-basin scale. The findings presented here provide valuable information for developing the sustainable watershed management strategies.