Estimating non-point source pollutant loads for the large-scale basin of the Yangtze River in China

Abstract

Taking advantage of the opportunity provided by the nationally funded Water Resources Integrated Planning and Investigation of China program (WRIPI), a model was established to estimate non-point source pollutant loads in a large-scale basin (ENPS-LSB) on the basis of hydrological processes and pollutant transport. The model made use of Environment for Visualizing Images software (ENVI) and Interactive Data Language (IDL) and took the characteristics of present-day China into account: a huge rural population scattered widely, marginal rural infrastructure and livestock cultivation based on scatterfeeding. The model was divided into two sections: one on dissolved and one on adsorbed pollutant loads. The dissolved loads were divided into four different types: those originating from agricultural fields, urban areas, rural residential areas, and livestock. The study was undertaken in the Yangtze River Basin. The results showed the chemical oxygen demand (COD), the total nitrogen (TN), the total phosphorous (TP), and the ammonia nitrogen (NH 3 -N) loads to be 2.6 9 10 6 , 1.6 9 10 6 , 9.3 9 10 5 and 3.1 9 10 5 tons, respectively, in the year 2000. The dissolved COD resulted mainly from rural residential areas and livestock; 76.8% of the dissolved TN and 86.4% of the dissolved TP produced were from agricultural fields. The Yangtze River Delta, the lower reaches of the Han River, and part of the Dongting Lake, Taihu Lake and Poyang Lake basins all had relatively high dissolved pollutant loads; adsorbed nitrogen and phosphorus loads were mainly observed in the middle and upper reaches of the Yangtze River Basin. Dissolved loads were most affected by human activity, whereas adsorbed loads were most affected by natural factors. The results showed that the model performed well on large scale, describing pollutant loads effectively. This makes it possible to properly consider not only point source pollutant discharge but also non-point source pollution in the Yangtze River Basin. Combining point source discharge investigation with the ENPS-LSB model could assist environmental management with controlling water pollution.

Simulating spatiotemporal variability of blue and green water resources availability with uncertainty analysis

“…Wang et al . () and Hong et al . () used the SWAT model to estimate non‐point source pollution in the Yellow River basin (YRB) and the Yangtze River basin.…”

“…Li et al (2011) andQiu et al (2012) simulated runoff and sediment in the Pearl River basin and the Zhifanggou watershed by using the SWAT model. Wang et al (2011) andHong et al (2012) used the SWAT model to estimate non-point source pollution in the Yellow River basin (YRB) and the Yangtze River basin. Guo et al (2008) and Li et al (2009) investigated the impacts of climate changes and human activities on hydrology and water resources in the Poyang Lake basin and the Loess Plateau by using the SWAT model.…”

Effects of water transfer on water quality and estimation of the pollutant fluxes from different sources into West Lake, Hangzhou City, China

“…The TP and TN concentrations in the West Lake have reportedly decreased in recent years (Guo 2005;Mao et al 2010); however, the TN concentration still remains at a high level and it is the major contaminant in the lake. The water quality of lakes and rivers is known to be influenced by many factors, including watershed land use characteristics, weather conditions, hydrological status, and policy (Drewry et al 2009;Wang et al 2011b). The annual average concentrations of TN,NH 4 ?…”

“…The concentration of a water sample was the annual average of the samples in this paper. These methods are appropriate for infrequent sampling to calculate pollutant fluxes based on the pollutant concentrations and flow, because the information of the pollutant concentrations is limited to relatively infrequent samples (Wang et al 2011b). Therefore, an interpolation method was adopted to calculate the pollutant fluxes of the transfer water (F s ) (kg):…”

Determination of the removal efficiency of a vortex-type facility as a best management practice using the dynamic event mean concentration: a case study of a bridge in Yong-In city in Korea

“…These types of pollutants are affected by rain and become discharged with runoff water from the ground surfaces (Dongquan et al 2009;Wang et al 2010). Nonpoint pollutants flow into rivers and thus can induce a toxic environment for the organisms living in the water or can cause damage to the ecosystem (Jalali and Kolahchi 2009).…”