From both natural and man-made aspects, let’s talk about the causes of frequent floods in the Yangtze River.

Natural aspects: 1. Rainfall is concentrated and intense. Most areas are controlled by the monsoon climate. Most of the annual precipitation is concentrated in the humid and high-temperature period in summer, and most of it occurs in the form of typhoons and rains. The rainfall from June to September accounts for 60-80% of the normal annual precipitation, and is often concentrated in During several heavy rains. 2. The seasonal displacement of monsoon rain belts leads to periodic stability of rainfall areas. The summer monsoon begins in May and advances from south to north. There are three corresponding rainy seasons, namely the South China rainy season (in the southern provinces, April to June), the Jianghuai-Mei rainy season (in the middle and lower reaches of the Yangtze River provinces, from mid-June to mid-July) and the North China rainy season. Northeast rainy season (North China and Northeastern provinces, mid-to-late July to August), when the monsoon is at its strongest. After September, the monsoon weakens and retreats southward, and the rain belt gradually retreats southward. After October, the monsoon withdraws from mainland my country and the rainy season ends. 3. Frequent typhoon activity in summer and autumn is also the main cause of flash flood disasters. After a typhoon lands along the coast, it usually turns northward around 300N~350N. The wind speed gradually slows down to form low pressure. If combined with the cold air from the north, it may form a large-scale heavy rain. Floods and flash floods. 4. Abnormal weather phenomena, such as El Ni?o, etc. 5. Other comprehensive natural factors.

Man-made aspects: Blind indiscriminate logging has caused serious water and soil erosion; natural lakes have decreased, and flood storage capacity has declined; activities such as mining, quarrying, road building, and canal digging have affected the stability of the mountains in the Yangtze River Basin, easily Causing flash flood disasters; flood diversion and flood control measures such as reservoirs and dams in the Yangtze River Basin are still not perfect and comprehensive, and there are artificial shoddy projects; early warning mechanisms and supervision mechanisms are not perfect and comprehensive; from a large perspective, in the process of human history development The act of destroying nature has changed and changed the original natural ecosystem, thus leading to abnormal climate and frequent natural disasters. Wait