A Research Study Submitted in Partial Fulfillment of the Requirement for the Degree of Masters of Science, School of Environment, Resources and Development

Research Studies Project Report (M. Sc.) - Asian Institute of Technology, 1994

Large scale and multi-purpose water resources project, particularly those with high dams, have various ecological impacts on the environment. The Three Gorges Dam Project, a large and multi-purpose water resources project on the Yangtze River in China with its high dam located in Hubei Province, is not an exception. This study assessed the ecological impacts of the project on the province. The impacts were identified, predicted and assessed, and mitigation measures were suggested to reduce and mitigate the significant negative impacts. At first, the study identified the impacts. The impacts are those on fisheries , Aquatic biology, terrestrial wildlife, and forest. To be more detailed and exact, the key impacts are the following: changes in the composition of fish species on the future reservoir, changes in reproduction and larva products of the four major farm fish species (carp, silver carp, variegated carp, and grass carp) in the main stem, changes in the fish replenishment for the lakes related to the main stem downstream, impacts on rare fish species---the white sturgeon and rouge fish, expansion of fishery in the future reservoir, impacts on the rare aquatic animal---the white-flag dolphin, changes in forest coverage, inundation of economic plants, changes in rare terrestrial vegetation species in the reservoir region, changes in terrestrial vertebrates. Then the study predicted and evaluated the impacts and found the following points: - Of the positive impacts and the negative impacts of the project on ecological aspects in the province, the negative ones are much stronger than the positive ones, and the aquatic ecosystem will be more affected than the terrestrial ecosystem. - Both the direct impacts and the indirect impacts ought to be paid the same attention to when we take the ecological impacts of the project on the province into consideration. - Among all the impacts, those on fisheries are the strongest ones, and all the impacts are negative except for the reservoir fisheries. At last, some mitigation measures for the negative impacts were recommended: - Setting up the protected sections for fishes.