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一、目前我国生态环境的基本状况1、水土流失面积有增无减。据有关资料介绍,建国以来,虽然水土流失面积已治理了58万平方公里,但全国水土流失总面积由建国初期的116万平方公里增加到现在的367万平方公里,治理的速度小于破坏的速度。每年流失泥沙50亿吨,泥沙带走的氮、磷、钾相当于我国每年化肥的总量。受水土流失威胁的耕地占耕地总面积的1/3。2、森林减少,草原退化。现在我国每年木材消耗量大于森林生长量,使森林面积遭到严重破坏,草原退化面积已占草原可利用面积的23%。建国初期,在川西地区森林覆盖率达40%,云南达50%,现在分别只剩下14.1%和24%。森林的破坏,
First, the current basic situation of China’s ecological environment 1, the area of soil and water loss increases unabated. According to relevant information, since the founding of the People’s Republic of China, although the area of soil erosion has been controlled by 580,000 square kilometers, the total area of water and soil erosion in China increased from 1.16 million square kilometers in the early days of the founding of New China to 3.67 million square kilometers now, and the rate of treatment is less than that of sabotage . Annual sediment loss of 5 billion tons of sediment to take away the nitrogen, phosphorus and potassium equivalent to the total annual amount of fertilizer in China. Cultivated land threatened by soil erosion accounts for 1 / 3.2 of the total arable land, forests are reduced and grasslands are degraded. Now that the consumption of timber in our country is larger than the amount of forest growth each year, the forest area has been seriously damaged, and the degraded area of grassland has accounted for 23% of the available area of grassland. In the early days after the founding of New China, forest coverage in western Sichuan reached 40% and that in Yunnan reached 50%, leaving only 14.1% and 24% respectively. The destruction of the forest,