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美国西部田纳西(Tennessee)地区最严重的水土保持问题是土壤的侵蚀,由于这个州土地肥力耗损,引起农作物产量降低,增大生产费用,减少土地价值.带着化肥和其它化学成份的土壤冲积物脱离了农田,正在污染州内各河流和水道.水土保持部分的近期研究证明,平均每亩水土流失量,到农田因洪水所致大面积水土流失量,田纳西州居合纵国首位.以至州范围内每年每英亩流失量竞达14吨左右.在田纳西西部地区流失程度甚致更严重,平均每年每英亩地差不多是40吨,在
Soil erosion is the most serious soil conservation problem in the western Tennessee region of the western United States, with reduced crop yields, increased production costs, and reduced land values due to depleted land fertility in the state. Soil alluvium with fertilizers and other chemical constituents From the farmland, is polluting the rivers and waterways in the state.Recent studies in the soil and water conservation section have proved that the average amount of soil erosion per mu to farmlands due to floods caused a large area of soil and water loss, Tennessee ranks first in the vertical and vertical. The annual loss of about 14 tonnes per acre is even more severe in the western part of Tennessee, averaging about 40 tonnes per acre on average