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一、洪灾对环境的破坏四川省1981年发生的洪灾,主要在沱江、涪江、嘉陵江、岷江流域20万平方公里范围内的人口稠密、交通方便、土地肥沃、物产富庶地区。这次特大洪灾,为什么集中在几条主要江河,涉及如此大的范围,损失如此之严重呢?究其原因,除不可抗拒的自然因素外,主要是人为活动破坏了环境和自然资源,生态平衡失调,抗御灾害力弱,加重了灾情危害。1、森林是环境中最大的生态系统,具有调节气候、涵养水源、保持水土、防风固沙、净化大气、改善环境等生物效能;破坏了森林就失去了生态平衡的主体,使环境恶
First, flood damage to the environment Sichuan Province in 1981 floods, mainly in Tuojiang, Fujiang, Jialing River, Minjiang River Basin within the scope of 200,000 square kilometers within the population and convenient transportation, fertile land, rich property areas. The reason why this extraordinary flood was concentrated in a few major rivers and covered such a large area is that the loss is so serious. Apart from irresistible natural factors, man-made activities mainly destroy the environment and natural resources and the ecological balance Disorders, defensive disasters are weak, aggravating the disaster hazard. 1. The forest is the largest ecosystem in the environment. It has the biological effects of regulating the climate, conserving water sources, preserving water and soil, preventing wind and sand, purifying the atmosphere and improving the environment. The main body that has lost the ecological balance when the forest is destroyed,