River pollution Rivers 5 Water quality 5 China 4 water pollution 4 water quality 3 Nitrogen 2 Phytoplankton 2 Quality control 2 Reservoirs (water) 2 Sewage 2 Water management 2 Water pollution control 2 Watersheds 2 Zhujiang Delta 2 human activity 2 index method 2 physicochemical property 2 phytoplankton 2 pollution control 2 AHP (analytical hierarchy process) 1 Adaptive boosting 1 Ammonia 1 Analytical Hierarchy Process 1 Antibiotics 1 Aquatic environments 1 Aquatic organisms 1 Article 1 Assays 1 Bacillariophyta 1