长江流域生态环境问题及其成因

分析长江流域上中游的水土流失与地质灾害、中下游的洪涝灾害、长江口的赤潮、长江水质污染、流域生物多样性变化、流域内人群健康等问题;论述了长江流域生态环境恶化的成因:森林植被的锐减是造成水土流失的主要因素,区域自然地理特征是洪灾和地质灾害的基础,污染物的大量排放造成了长江水质的污染和长江口的赤潮,水利设施的兴建使得濒危物种增多,城市化增加了洪灾损失;提出了保护和恢复长江流域和谐生态环境的有效措施:增加环境建设的投入和增强人们的环保意识,重视森林植被的保护等.

Eco-environmental problems in Yangtze River Basin and their causes of formation

An analysis was made on some eco-environmental problems in Yangtze River Basin,including water and soil erosion and geological disasters on the upper and middle reaches,the flood disasters on the middle and lower reaches,the red tides at the river estuary,the water pollution in the river,the variation of biodiversity and human health in the river basin,and so on,and the causes of deterioration of eco-environment in the river basin were discussed.Some conclusions are drawn as follows: the sudden decrease of forest and vegetation is the main cause of water and soil erosion;the regional geographic characteristics make it possible for the formation of flood and geological disasters;great amounts of pollutant discharge result in water pollution in the Yangtze River and red tides at the river estuary;the construction of water conservancy facilities threatens the biodiversity;urbanization increases the loss of floods.Finally,some effective measures for protecting and rehabilitating eco-environment in the Yangtze River Basin were proposed,such as increasing the investment in environmental construction,strengthening the awareness of environmental protection,paying much attention to protection of forest and vegetation,etc.