The Status of Pollutants in the Three Gorges Reservoir Area, China and its Ecological Health Assessment

The Three Gorges Reservoir Area (TGRA) stretches along the Yangtze River from Jiangjin District, Chongqing to Yichang, Hubei in China. Since TGRA is the main source of drinking water and fresh fishery in China for millions of people, both researchers and the government have concerns for environmental pollution and ecological security in the TGRA. This review highlighted the status and trends of primary water pollutants/parameters in the TGRA and evaluates their impacts on its ecological health for nearly 12 years. In this study, we analyzed the published data including the bulletin on the ecological and environmental monitoring results of the three gorges project, statistical yearbook data from years 2004 to 2015 and published articles. Chemical indicators model was applied to elucidate the ecological health of TGRA based on nitrogenous compounds, phosphorus compounds, organic reducing substances, volatile phenol and heavy metals (Cr, Cd, Cu, Hg, As and Zn). The results showed that the ecological health conditions slightly varied during these years in the TGRA. Moreover, the value of ecological health in spring, summer and autumn was lower than that in winter. Generally, the overall ecological health of the TGRA during these 12 years seems to be stable. Although the ecological health of TGRA is good, there is an urgent need to strictly implement the industrial discharges standards to assure the ecological integrity and sustainable development of the TGRA.