Simulation and evaluation of pollution load reduction scenarios for water environmental management: a case study of inflow river of Taihu Lake, China.

Ruibin Zhang,Wei Hu,Wenting Zhu,Jinhua Wang,Hailong Gao,Xin Qian

doi:10.3390/ijerph110909306

Abstract

In the beginning of the 21st century, the deterioration of water quality in Taihu Lake, China, has caused widespread concern. The primary source of pollution in Taihu Lake is river inflows. Effective pollution load reduction scenarios need to be implemented in these rivers in order to improve the water quality of Taihu Lake. It is important to select appropriate pollution load reduction scenarios for achieving particular goals. The aim of this study was to facilitate the selection of appropriate scenarios. The QUAL2K model for river water quality was used to simulate the effects of a range of pollution load reduction scenarios in the Wujin River, which is one of the major inflow rivers of Taihu Lake. The model was calibrated for the year 2010 and validated for the year 2011. Various pollution load reduction scenarios were assessed using an analytic hierarchy process, and increasing rates of evaluation indicators were predicted using the Delphi method. The results showed that control of pollution from the source is the optimal method for pollution prevention and control, and the method of “Treatment after Pollution” has bad environmental, social and ecological effects. The method applied in this study can assist for environmental managers to select suitable pollution load reduction scenarios for achieving various objectives.

Highlights

The pollution load of Taihu Lake Basin, China is primarily from river inflows
The concentrations of chemical oxygen demand (COD), NH3-N, total nitrogen (TN), and total phosphorus (TP) reduced suddenly at 14 km downstream because of large quantities of water with low concentrations of pollutants from the Xilicao River tributary flowing into Wujin River
The results show that pollution load of only non-point sources needed to be reduced by 17.14%, 29.73%, 40.06% and 62.59% for COD, NH3-N, TP and TN concentrations, respectively, to meet the standards

Summary

Introduction

The pollution load of Taihu Lake Basin, China is primarily from river inflows. The key to protecting the water environment of the lake is interception of pollutants in these river inflows. Pollution of rivers is one of the most prominent water environmental problems, and is closely related to economic development and quality of life in the region [4,5,6,7]. To solve these environmental problems, managers must select appropriate pollution load reduction scenarios for achieving particular goals, decisions between alternative scenarios can be a difficult task for water environmental managers.

Methods

Results

Conclusion