Study of water pollution load prediction and pollution economic loss in coastal zone based on system dynamics: a case study of Jiangmen city

Base on system dynamics coupled with water pollution load model and concentration-loss model, the coastal zone water pollution system model was established to simulate water pollution load and economic loss in the Jiangmen coastal zone from 2006 to 2015. Four development scenarios:development under the current trend (S1), rapid development in population and economic (S2), industrial optimization and pollution control (S3), comprehensive scenario (S4), are simulated, in order to predict the potential pollution load and economic loss from the year 2016 to 2020. Results show that:1) For all the four development scenarios, agricultural pollution mainly contribute to the pollutants of COD, NH₃-N and TP in Jiangmen coastal zone, while domestic pollution is the second source; 2) Scenario of S4 will be the best, in which the coastal zone pollution load will be controlled and marine pollution economic loss will be the minimal; The total pollution load and economic loss will be decreased by 7.9% and 17.7%, compared to S1, respectively. Therefore, under the circumstances of reasonable constraint of population and economic development, coastal pollution load and pollution economic loss can be effectively reduced by industrial structure optimization and increasing investment in pollution control and environmental protection. This study not only provides quantitative reference to the control and management of water pollution for Jiangmen, but provides reference for the harmonious development of society, economy and environment of other coastal cities like Jiangmen city.