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在美国,土壤风蚀仍很严重。虽然不象美国中南部曾经出现过的尘暴(Dust Bowl)天气那样,但目前有些地区不仅仅是天空浑浊,更严重的是几厘米的地表土被风吹走了。 并不是旷野阻止了再一次尘暴的发生,而是由于美国农业部农业研究中心研究推广的新的水土保持措施起了作用。 风仍然被认为是侵蚀作物地的一个外营力。1986年美国密西西比河流域以西的大平原风灾土地面积达340万ha,相当于美国中南部曾经出现过的尘暴受
In the United States, soil erosion is still very serious. Although not like the Dust Bowl weather that has taken place in central and southern United States, some areas are now more than just cloudiness in the sky, but more seriously, a few centimeters of surface soil is blown away. It is not the wilderness that has prevented another dust storm from happening, but the new soil and water conservation measures promoted by the Agricultural Research Service of the United States Department of Agriculture. The wind is still considered as an external force that erodes the crop. The Great Plains hit the west of the Mississippi River in 1986 with an area of 3.4 million ha, equivalent to the dust storms that once occurred in the central south of the United States