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长江流域面积180万平方千米,干流及沿途汇入的支流,流经多样的地貌类型,气候差异显著,各河段的落差也有所不同,还有大量的附属湖泊,形成了多样的生态环境,是我国淡水鱼类资源最为丰富的地区。但是,近些年来,因为日益恶化的水质及干、支流上林立的大坝和毫无节制的捕捞等因素,使得长江中的鱼类急剧下降,众多珍稀鱼类更是面临濒危乃至灭绝的境地。
The Yangtze River basin covers an area of 1.8 million square kilometers. The mainstream flows along the tributaries that flow in along the route flow through a variety of landform types. The climate differences are significant. The differences between the river sections are also different. There are also a large number of ancillary lakes forming a diverse ecological environment , Is China’s most abundant freshwater fish resources areas. However, in recent years, the number of fish in the Yangtze River has plunged due to deteriorating water quality and dry and tributary dams, and uncontrolled fishing. Many rare fish are even more endangered or even extinct .