water pollution River pollution 4 Article 3 China 3 Water quality 3 human 3 water quality 3 Adsorption 2 Phytoplankton 2 Reservoirs (water) 2 Rivers 2 United States 2 Water pollution 2 Zhujiang Delta 2 adsorption 2 arsenic 2 controlled study 2 diffusion 2 human activity 2 phytoplankton 2 AHP (analytical hierarchy process) 1 Acidic drugs 1 Adaptive boosting 1 Air Pollution 1 Alginate 1 Alternate water sources 1 American 1 Analytical Hierarchy Process 1 Aquatic environments 1 Aquatic organisms 1