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近年来保守耕作(Conservation tillage)在美国、巴西、中国很快推广。与几千年来包括有翻耕、整地、播种的传统耕作相比,保守耕作具有很多优点。诚然,传统耕作可以使土壤疏松,氧气和养分渗入下层,可使种子加速萌发,加快根系生长。但这些优点要在除去杂草情况下才显现出来。最近,世界各地纷纷讨论土壤流失的问题,即多年来形成的肥沃的表土被雨水或风侵蚀。据统计,美国每12年即损失1厘米厚的表土,按每公顷计约为10吨重,在约25％的田块中表土损失速度大于表土形成速度。由于翻耕、整地使土壤流失现象加重。另
In recent years, conservation tillage (Conservation tillage) in the United States, Brazil, China soon to promote. Conservative farming has many advantages over traditional farming that has included tilling, land preparation and sowing for thousands of years. It is true that traditional farming can make the soil loose, oxygen and nutrients into the lower, can accelerate the germination of seeds and accelerate root growth. However, these advantages only appear when the weeds are removed. Recently, the issue of soil erosion has been discussed all over the world, that is, the fertile topsoil formed over the years has been eroded by rain or wind. According to statistics, about 1 tonne of topsoil lost every 12 years in the United States is about 10 tons per hectare. In about 25% of the plots, the loss of topsoil is greater than that of topsoil. As a result of tillage and land preparation, soil erosion is aggravated. another