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在孟加拉的恒河、美国的密西西比河和马达加斯加岛上的贝戚布卡河,河口三角洲地都已显出由于中上游地区砍伐森林和过度使用土地所造成的恶果。太空中飞行的宇航员曾在巴西亚马孙盆地上空看到过一块烟云,并为这世界最大烟云拍照。它几乎笼罩了1/3的南美大陆。烟云是由于热带雨林乱伐后燃烧所造成。在埃及,阿斯旺水坝后面的纳森湖,由于常年淤积湖面尺寸已经发生明显变化。证明这种变化所产生影响的明显证据是,苏丹青、白尼罗河交汇处最近发生的
Both the Ganges in Bangladesh, the Mississippi in the United States and the Bibimbuka and Madagascar islands in Madagascar have shown the detrimental effects of deforestation and over-use of the land in the upper-middle reaches. Astronauts flying in space have seen a cloud of smoke over the Amazonian basin in Brazil and take pictures of the world’s largest cloud of smoke. It is shrouded in almost 1/3 of the South American continent. Clouds are caused by the burning of tropical rainforests. In Egypt, Lake Nathan behind the Aswan Dam has changed significantly due to the size of the lake. Evidently evidence of the impact of such changes is the recent occurrence of the Sudan-White Nile Interchange