一、材料和方法本试验于1986～1987年在剑河县岑松镇对门寨村冲沟田进行,海拔为600米,年降雨量为1100毫米,年平均气温16.5℃,4～10月月均气温在16.9℃～26.1℃,无霜期299天。土质为砂壤,前作为垄作免耕绿肥田和垄作油菜田,肥力中下等。在绿肥田上进行免耕与耕的对比试验,3次重复,6个小区,小区面积为0.11亩;辅助试验1组,不设重复,小区面积0.50亩。在油菜田上进行免耕与耕和免耕、耕与换垄两项试验。免耕与耕试验设2个重复,4个小区,小区面积0.25亩,免耕、耕与换垄试验由于换垄沟垄换位,田间排列不便设置重复, I. MATERIALS AND METHODS The experiment was carried out in Chengshen Town, Jianhe County from 1986 to 1987 to Chongzhai, Menzai Village, at an altitude of 600 meters with an annual rainfall of 1100 mm and an annual average temperature of 16.5 ° C. From April to October Average temperature is 16.9 ℃ ~ 26.1 ℃, frost-free period of 299 days. Soil as a sandy soil, before the ridge as a no-tillage green manure and ridge rape fields, fertility and inferior. No-tillage and tillage in green manure field experiments, 3 replicates, 6 plots, plot area of ​​0.11 acres; auxiliary test 1 group, no duplication, plot area 0.50 acres. Two trials of no-till and no-till, no-till and no-till have been conducted on canola fields. No-tillage and tillage were set up with two replicates, four plots and a plot area of ​​0.25 mu. No-tillage,