Assessment of the environment effects of constructing the Three Gorge Project on the Yangtze River
The Three Gorge Project is a multipurpose project with the primary function of flood control. Other functions include power and navigation and could include irrigation. A 200 m high concrete gravity dam, currently being considered, would be located in the lower reach of the famous Three Gorges of the Yangtze River in Hubei and Sichuan Provinces. The reservoir will store about 70 x 10 to the 9th cu m and extend upstream about 780 km. The proposed powerplant would have an installed capacity of 25,000 MW, consisting of twenty-five 1000-MW units. The Three Gorge Project, when constructed, would be the largest water resource project anywhere on earth. Beneficial effects include elimination of flooding along the middle and lower reaches of the Yangtze River, a substantial increase in much needed electric power for south and central China, and creation of a large body of water which could be used for aquaculture. Consideration is also being given to diverting water to the North China Plain, one of the most important agricultural areas of China. Major adverse impacts include relocation of more than 2 million people for the reservoir area; loss of habitat for many kinds of Yangtze River aquatic life, including themore » unique Chinese sturgeon; and the possibility of reducing nutrient input to the downstream and estuarine fisheries. The possibility of minimizing adverse effects seems high, if the potential environmental impacts are identified and means of mitigation are carried out. 22 references, 1 figure.« less
Runoff Regulation for Hydropower and its Effects on the Ocean Environment
It has not yet been recognized that modification of the natural seasonal discharge of rivers might result in significant consquences to the ecology of the adjacent marine environment. An example of such regulation is the St. Lawrence system in which, in order to optimize power production, large quantities of water from the spring runoff are retained in storage lakes and returned to the river during the low natural discharge period of autumn and winter. It has been estimated that under present conditions the spring and summer runoff at the entrance to the Gulf of St. Lawrence has been reduced by between one third and one half.This drastic alteration of the natural runoff has caused significant changes in the physics and dynamics of the waters of the Estuary, Gulf, and adjacent coastal region. It is argued that such modifications produce a profound impact on the biological balance of the whole ecosystem, as well as changes in the seasonal heat budget.
EROSION OF BANKS OF STORAGE RESERVOIRS IN POLAND
ABSTRACT The abrasion of banks of certain storage reservoirs can have considerable importance. Cases are known where the shift of the bank line forecast to take place within a period of ten or fifteen years was exceeded during the first year of operation of the reservoir. However, transformation and erosion of banks in other reservoirs or other bank sections, although anticipated, either has not occurred, or, when it did, its intensity was much lower than expected. This is why the problem of transformation of the near-shore zone in reservoirs is attracting more and more attention from many scientific institutes. The paper presents the subject, methods and results of research on the transformation and erosion of the reservoir banks. The main effort has been concentrated on trying to establish the relationships between geological-morphological and climatic-hydrological conditions. It has been stated that the dynamic potential of the reservoir is of decisive importance. This potential, depending on the morph...