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The Dust Bowl from the Great Plains happened on May 11, 1934, covering half the nation with a thin layer of grit. This was an expensive lesson in the ecological history of the United States.
From both economic and ecological viewpoints, most of the Great Plains is better suited to grazing than to farming. Yet several times over the last century, prolonged periods of good rainfall have encouraged a counterfeit optimism about the capacities of the Plains among newcomers, and even among many long-time residents. Humans have repeatedly extended their farms and expended their cattle herds beyond safe levels during the wet years, to be brought rudely back to reality when the drought cycle returned.
The Dust Bowl of the thirties catalyzed a main turn on soil conservation practices in America. After the unprecedented dust storms soon followed by the formation, in 1935, of a Soil Conservation Service, federal promotion of soil conservation practices in the Great Plains. From then on, the soil erosion research and soil conservation practices had been improved little by little. However, forces from free market were promoting a recession of soil conservation, which is a challenge for the government and soil conservation workers.
Similarly, the ecological lessons were learned by the Soviet Union. During 1960s,the virgin lands, in western Siberia, and eastern Russia, once became the another American Dust Bowl because of misleading on politics and chasing for high grain production.
In sum, the two costly lessons, the Dust Bowl and the Virgin Lands, are the great important events on the development of the world soil conservation.
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