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

Abstract

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.

Disentangling the role of environmental filtering and biotic resistance on alien invasions in a reservoir area

“…It is worth noting that the number of species of malignant invasive plants and serious invasive plants found in this survey accounted for 56.8% and 46.0% of the total in China, respectively, which demonstrated that invasive alien plants pose a great threat to the ecological security of the region. As observed in previous studies (Lu, 2014), invasive plants are mainly annual and/or biennial herbs, due to their ability to respond to environmental changes by generating a large number of seeds in a short period of time, whereas alien perennial and woody plants may require a longer time to complete their life cycle (Bonser & Ladd, 2011). It cannot be ignored that in the TGRA, some alien perennial grasses such as Alternanthera philoxeroides, Ageratina adenophora, and Eichhornia crassipes, have had devastating consequences on ecosystems as well (Chen et al, 2017;Zhang & Xie, 2021).…”

Evaluation of ESV Change under Urban Expansion Based on Ecological Sensitivity: A Case Study of Three Gorges Reservoir Area in China

“…The eastern part is close to the Daba Mountain and has many rolling hills [39]. There are abundant vegetation types in the Three Gorges Reservoir area, and the overall spatial distribution of vegetation coverage shows the characteristics of high in the east and low in the west [40]. The east is mostly broad-leaved forests, bushes and grasslands; the central and western area are farming area with many cultivated plants and crops [41].…”

Investigation of factors contributing to accumulation of sediments in stormwater management ponds

“…The pond will suffer from erosion, instability and sediment accumulation. Hydrologic parameters include imperviousness, infiltration approach, variables required for hydrograph computation, channel routing, and reservoir routing controls (Lu, 2016). The main purpose of hydrologic data is to provide the information relating to peak flow rates and volumes, helps in calculating sediment accumulation rates.…”