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根据中美农业科技合作计划,我们一行六人赴美国考察水土保持,并了解灌溉、防洪等情况,历时一个月,先后访问了八个州、五十八个单位。四十七年间的发展美国存在水土流失,部分地区还是很严重的。据统计,一九七七年全国土壤流失量约四十亿吨,其中耕地面蚀达二十亿吨。属于黄土区的田纳西州西部、衣阿华州西部和密西西比州西北部等地区的水蚀,美国西部、西南部的风蚀都是相当严重的。据衣阿华州水土保持局负责人介绍,该
According to the Sino-U.S. Cooperation in agricultural science and technology, our team of six went to the United States to study soil and water conservation and to understand the situation of irrigation and flood control. After a month’s visit, we visited 58 states and 58 units successively. During the 47 years of soil erosion in the United States, some areas are still very serious. According to statistics, in 1977, there were about 4 billion tons of soil erosion in the country, of which the surface erosion of cultivated land reached 2 billion tons. Water erosion in western Loess, western Tennessee, western Iowa and northwestern Mississippi are all serious problems with wind erosion in western and southwestern United States. According to the person in charge of Iowa State Soil and Water Conservation Bureau, the