水电站与环境污染

WWF Says Pollution, Dams Threaten Rivers

By ELIANE ENGELER, March 19, 2007.

GENEVA - The Yangtze River gets more than half of China's industrial waste and sewage. Europe's Danube has lost most of its surrounding wetlands. And the Rio Grande has become so shallow that salt water is seeping in, bringing ocean fish that threaten freshwater species.

Pollution, global warming and rampant development could destroy some of the

world's most iconic rivers in the coming decades, threatening to wipe out thousands of fish species and cause severe water shortages, the World Wide Fund for Nature said

in a report Tuesday.

Only 21 of the planet's 177 longest rivers run freely from source to sea, with dams and other construction destroying the habitats for migratory fish and other species by altering the water's natural ebb and flow, the WWF said.

About a fifth of the world's 10,000 freshwater fish and plant species are either extinct or endangered, the report said, calling on governments to radically step up efforts to preserve rivers, lakes and wetlands.

"Unabated development is jeopardizing nature's ability to meet our growing demands," said Jamie Pittock, who heads WWF's freshwater program.

The report focused on some of the world's most important rivers: the Nile, the Da nube, the Rio Grande, South America's La Plata, Australia's Murray-Darling and Asia's Yangtze, Mekong, Salween, and Ganges rivers.

The Danube — home to more than half of Europe's fish species — has lost 80 percent of its surrounding wetlands and flood plains because of dams, the report said.

Construction to ease shipping channels — dredging, pumping water or straightening banks — also threaten animals and plants in the river, which runs from Germany to the Black Sea, WWF said. Less than 7 percent of its basin is protected.

In China, pollution in the main stem of the Yangtze River has increased by more than 70 percent over the last 50 years. Almost half of the country's industrial waste and sewage is discharged in the river, the report said.

Garbage heaps, pig waste and discharge from factories, hospitals and mines —possibly including radioactive waste — lie at the bottom of the reservoir at the Three Gorges Dam, the world's largest hydroelectric project, the WFF said.

In the Rio Grande, low water levels have allowed salt water to enter and ocean species to crowd out freshwater fish. Excessive extraction, primarily for agriculture, is threatening the river, which flows along the U.S.-Mexican border.

At the same time, rising populations along both sides of the river need more and more water, increasing pressure on the 69 fish species found only in the Rio Grande, the WWF said.

Global warming is threatening fish populations in Africa, where even small temperature changes can dramatically alter water levels and fish productivity, the report said. The Nile, the world's longest river, is expected to reach a critically low level by 2025, threatening a source of drinking water for thousands of years.

全球多处水坝对社会与环境造成严重威胁

文章来源：互联视窗添加人：vincent添加时间：2005年11月23日

本报讯世界自然基金会近日指出：尽管世界水坝委员会5年前对大坝的建设给出了具体的、有利于可持续发展的建议，但5年后的今天，大坝仍然对社会和环境造成过多的损害。

该报告表明，大坝会使重要的水源地——湿地受到破坏、淹没甚至干涸，还会对渔场和濒危物种如伊比利亚猞猁和美洲虎等带来灭顶之灾。在承诺提供更廉价的电力或更好的灌溉水源同时，水坝实际上会扰乱经济体系，使电价上涨和众多居民迁移。

“现在已经不是20世纪50年代那样以工程为主导的时代了，那时大坝被视为发展的标志——而现在我们已经知道大坝会带来破坏，我们必须让这些知识发挥作用，”世界自然基金会的全球淡水项目主任杰米·皮塔克说，“各国政府和世界银行必须坚持世界水坝委员会的建议适用于今天所建的所有大坝项目。”

在中美洲国家洪都拉斯的首都伯利兹，投资3000万美元的Chalillo水坝工程原本是为了减少电力进口和降低电价，但自从完工以来，当地居民却发现电价平均上涨了12%，而且水库淹没了1000公顷的原始雨林。根据世界自然基金会的资料，土耳其投资6.5亿美元的埃尔梅内克坝以及另外5座水电站工程，正导致国际重要湿地格克孙河三角洲没有足够的水流量来维持栖居于此的野生动植物的多样性。同时，在老挝，由于世界银行批准的南屯河2号水电站的修建，南屯河的水被分流，将有5万人的生计受到影响。分流导致邦非河的流量增加，造成渔场和农业用地的减少。报告还强调，经济合作与发展组织（OECD）发现，