Evaluation of non-point source pollution based on grey water footprint method: A case study in the urban agglomeration of Shenzhen, Dongguan and Huizhou

Abstract

Based on a grey water footprint method, NPS pollution in the urban agglomeration of Shenzhen, Dongguan and Huizhou was evaluated in this research. The results showed that the NPS pollution level in this urban agglomeration decreased from 1995 to 2019. The grey water footprint of NPS pollution in the cities of Shenzhen, Dongguan and Huizhou had similar variation characteristic, which showed a trend of first increasing, then decreasing, and finally increasing during the research period. The largest source of grey water footprint of NPS pollution was land use, followed by livestock and poultry breeding. The water pollution level of NPS pollution was highest in Shenzhen and lowest in Huizhou, which was in the same order as gross domestic product (GDP) in this agglomeration. Thus, city governments should attach more importance to prevention and control of NPS pollution in the process of economic development, especially for land use source.