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美国水上流失也较严重,全国总面积936万km~2,其中强烈水蚀面积114万km~2,占总面积的12.2%,风蚀面积310万km~2、占33%,年土壤侵蚀量高达64亿t。经过60多年的连续治理,取得了显著成绩。相当一部分地方已经完全控制了水土流失,建立了良好的生态环境,其治理措施和我国大体一致,只是在具体方法上有所不同。1.梯田建设技术。美国人均占有耕地多,坡耕地坡度较缓,农业机械化程度高。梯田建设中以软埂和草埂梯田为主,主要有3种形式。
The water loss in the United States is also more serious, with a total area of 9.36 million km2, of which 1.14 million km2 is strongly eroded, accounting for 12.2% of the total area. Wind erosion area is 3.1 million km2, accounting for 33% 6.4 billion tons. After more than 60 years of continuous management, remarkable achievements have been made. A considerable part of the localities have completely controlled soil and water loss and established a good ecological environment. Their governance measures are generally in line with those of our country, but only differ in specific ways. 1. Terraced construction technology. Americans occupy more arable land, slopes slope more slowly, a high degree of agricultural mechanization. Terraced fields are dominated by soft and grassy terraces, mainly in three forms.