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集约耕作移动了大量土壤,把表层土壤从凸起的位置挪到凹地沉积。美国学者K.Pap iern ik等人于2000年开始研究了耕作侵蚀对土壤性质及作物产量的影响。求出每年铧式犁耕作的波浪形地面上的作物产量(连续4a)、表土性质和侵蚀估计值的方差。结果表明,在高度耕作侵蚀的地区,钙质底土上翻和表土混合使表土无机碳含量增加。在2000、2001和2003年,这些地方的小麦产量最低,比往年减产50%,甚至更多。相反,由于耕作和水的侵蚀使土壤沉积的地方,小麦产量是最高的。这些地方的表土层较深、有机碳含量高、pH值低、无机碳含量高。2002年的大豆产量和地形因子相关性不大。这些结果表明连续集约经营使土壤移动,会严重影响不平地形上的作物产量的有效性;需要找准时机采取补救措施减少产量损失。
Intensive farming moved a large amount of soil and shifted surface soils from raised locations to depressed deposits. American scholar K.Papiern ik and others began to study the impact of tillage erosion on soil properties and crop yield in 2000. The variance of crop yield (continuous 4a), topsoil properties, and erosion estimates for the waverhed plots per year of plow was calculated. The results show that in the highly tillage and eroded area, upturn of calcareous subsoil and mixing of topsoil increase the content of inorganic carbon in topsoil. In 2000, 2001 and 2003, wheat production in these areas was the lowest, a 50% reduction from previous years or more. In contrast, wheat yields are highest where soil is deposited due to tillage and water erosion. The topsoil in these areas is deep with high organic carbon content, low pH and high inorganic carbon content. The correlation between soybean yield and topographic factors in 2002 is not significant. These results indicate that continuous and intensive operations that move soils can seriously affect the effectiveness of crop yields on uneven terrain; and find time to take remedial measures to reduce production losses.