1979～1985年,在小麦-玉米一年两熟种植方式中,以耙地并投入玉米秸或投入玉米秸和小麦秸代替传統的麦前翻耕法,结果表明,“少耕”和“培肥”相结合,可以全面改善土壤营养状况和土壤水分状况,耙层土壤容重偏小,促进小麦根系和地上部的生育,使小麦、玉米增产。便耙秸还田延至三、四年,耙层下部的容重比对照偏大,耙层的容重亦逐漸大于对照,影响根系良好发育,小麦、玉米不再表现增产。据此,提出了在小麦-玉米一年两熟方式中,將小麦播前翻耕的传統耕法改为耙、耕交替,即耙秸两年,翻耕一年的土壤耕作制。以改善土壤的营养和物理状况,提高作物产量,降低成本。并克服连续耙秸,土壤容重增大,有碍作物根系生育的缺点。 From 1979 to 1985, in the two-cropping system of wheat-corn a year, rake and corn straw or corn straw and wheat straw were used instead of the traditional wheat tillage method. The results showed that “less tillage” and “ Fertilize, ”which can comprehensively improve the soil nutrient status and soil moisture status. The soil bulk density of the raking layer is small, promote the growth of wheat roots and shoots, and increase the yield of wheat and corn. They rake straw field to three or four years, the bulk density lower than the control rake layer is relatively large, the weight of the rake layer is also gradually greater than the control, affecting the root well-developed, wheat, corn no longer yield performance. Therefore, it is proposed to change the traditional tillage method of tillage wheat before sowing into rake and tillage alternation in wheat-corn one-year-two-year mode, that is to say cultivating tillage for two years after raking straw for one year. To improve soil nutrition and physical conditions, increase crop yields and reduce costs. And to overcome the continuous rake straw, soil bulk density increases, hinder the crop root growth defects.