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洪水的原因1.暴雨长江的洪水是暴雨型洪水,根据近年统计的结果,长江中下游的梅雨期延长,同时又逢长江上游西南暖温气流影响,上游暴雨季节与中下游梅雨期重叠,形成全流域的洪水。更由于暴雨区域范围可达数万平方公里,而且暴雨移动方向与长江径流方向一致,使上、中、下游洪水遭遇,极大地增加了洪灾的威胁。更值得关注的是由于区域性暴雨造成的区域性洪水灾害。从全球气候变化的角度来说,不排除厄尔尼诺现象的影响。但是值得注意的两点是:第一,同受全球性的厄尔尼诺现象的影响,也同样受上游植被破坏的水土流失的影响,长江连续出现洪水,而
Reasons for the Flood 1. Heavy Rain The flood in the Yangtze River is a stormy flood. According to the statistics of recent years, the rainy season in the middle and lower reaches of the Yangtze River is prolonged. At the same time, it is affected by the southwest warm air flow in the upper reaches of the Yangtze River. The upstream rainy season overlaps with the mid- Floods throughout the river basin. More due to the rainstorm area up to tens of thousands of square kilometers, and heavy rain movement direction and the direction of the Yangtze River runoff, floods in the upper, middle and lower reaches, greatly increased the threat of flooding. Even more noteworthy is the regional floods caused by regional torrential rain. From the perspective of global climate change, the impact of the El Niño phenomenon is not ruled out. However, two notable points are: First, the same impact of the global El Niño phenomenon is also affected by the soil and water loss caused by the vegetation damage in the upper reaches. Floods continue to occur in the Yangtze River,