西安建筑科技大学：《水资源利用与保护》参考资料_Water resources in the world_Watersheds of the World - Existing and Proposed Major Dams

Watersheds of the World -Existing and Proposed Major Dams 的感 oposed Major Dams O Number of major dams currently planned or under p Projection: Robinson Citation: Revenga, C- S Murray, I. Abramovitz, and A. Hammond, of the Work Ecological value and vulnerabilty. Washington, DC: World Resources Institute. eEarthTrends 2002 Work

Watersheds of the World - Existing and Proposed Major Dams Map Projection: Robinson Citation: Revenga, C., S. Murray, J. Abramovitz, and A. Hammond, 1998. Watersheds of the World: Ecological Value and Vulnerability. Washington, DC: World Resources Institute. © EarthTrends 2002 World Resources Institute. All rights reserved. Fair use is permitted on a limited scale and for educational purposes

Analytical Overview: m map shows the number of existing and planned major dams by basin as of 19 am Construction Handbook, 1995. A small subset of 56 major dams planned or city of at least 25 h政a1h边mha meters, reservoir storage capacity was at least 25 cuhic kilometers, or generating capacity note that informat and small dams, bowever, is only available for the States, therefore, these are not included in this map. hi by at least found in North America, Europe, and the Parana basin in South America. The countries was not availab! situate hosed on Institute, 199 of Dams database, Army Cocps of Engineers, 1995-1996. e EarthTrends 2002 World Resources nstitute. Al right

Analytical Overview: Source: A complete digital dataset of 306 major dams was created for this project using the list, "The World's Major Dams and Hydro Plants," from the International Water Power and Dam Construction Handbook, 1995. A small subset of 56 major dams planned or under construction in 1994 was selected using the list, "Large Dams Under Construction," from the same publication. Each major dam was selected using the following criteria: dam height was greater than 150 meters, water volume was greater than 15 million cubic meters, reservoir storage capacity was at least 25 cubic kilometers, or generating capacity was greater than 1,000 megawatts. It is important to note that information on dam construction for many countries was not available. Revenga, C., S. Murray, J. Abramovitz, and A. Hammond, 1998. Watersheds of the World: Ecological Value and Vulnerability. Washington, DC: World Resources Institute, based on data from "The World's Major Dams and Hydro Plants" and "Dams (>15m) Under Construction," International Water Power and Dam Construction Handbook, 1995; ArcAtlas: Our Earth database, Environmental Systems Research Institute, 1997; and National Inventory of Dams database, Army Corps of Engineers, 1995-1996. Description: This map shows the number of existing and planned major dams by basin as of 1994. A major dam is defined as having a height greater than 150 meters, a water volume greater than 15 million cubic meters, a reservoir storage capacity of at least 25 cubic kilometers, or a generating capacity greater than 1,000 megawatts. All major dams are included in the map. However, rivers are also fragmented by hundreds of large dams (those that are over 15m high) and thousands of small dams (those with a height below 15m). There are more than 40,000 large dams worldwide, and up to 800,000 small dams. A comprehensive list of large and small dams, however, is only available for the United States; therefore, these are not included in this map. Dams can be indicators of the degree of modification of a river. Most major rivers in the world have been heavily dammed. Of the 106 watersheds analyzed, 46 percent have been modified by at least one major dam. Most of the major dams in the world are found in North America, Europe, and the Paraná basin in South America. The Paraná basin alone has 14 major dams. As of 1994, 56 additional major dams were planned or under construction around the world. Just five watersheds account for the majority of the 56 proposed dams-- led by the Yangtze with 11, the Tigris and Euphrates with 7, the Ganges with 6, and the Hwang He and Paraná with 4 each. It is important to note that information on dam construction for many countries was not available. © EarthTrends 2002 World Resources Institute. All rights reserved. Fair use is permitted on a limited scale and for educational purposes