| Agricultural regions in the United States are greatly affected by erosion. Geologists estimate that the continents naturally lose up to twenty metres of soil. This phenomenon is counteracted by the Earth’s natural regeneration process. But in the United States today, soil loss is reaching 500 metres per million years, or 25 times more than the natural rate of erosion. The soil regeneration process cannot make up for losses at this rate. Between 1982 and 2001, measures such as leaving strips of grass close to watercourses, or furrow strips at right angles to the slope have enabled 43% of the land threatened by erosion to be retained. Worldwide, it is estimated that a third of all arable land has been lost to erosion in the past forty years. Some 10 billion hectares are affected by this phenomenon each year. Current levels of human activity, which result in erosion on average ten times greater than that caused by natural processes, is not sustainable in the long term.
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.&title2= Agricultural landscape around Idaho Falls, Idaho, United States (43°28’ N, 112°01’ W).&title3= "download in wallpaper")
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