Soil erosion in the world is about 25 billions tons each year. Because of land to be deserted serious day by day and plowing by machine and using pesticide and chemical fertilizer which causes land pollution and lowering land quality. But their land quality of mainly agricultural countries such as Brazil, US and Russia is still good, in Europe and America organic content in soil keeps 2.5-4%， sandstorm in Brazil and Russia don’t almost happen, American sandstorm is going weakly since 1950s, so land desertification is being weakly compare with us.(to be proofread)
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