【摘要】 三段式心土混层犁为改造白浆土土体构型实现了“上翻 2 0 cm,下混 30～ 40 cm”的农艺要求 ,白浆层与淀积层的土壤混拌率 Mx 达到 0 .7,白浆层向淀积层的土壤转移率 TAw→ B达到了 0 .3。 0～ 40 cm土层土壤物理性状明显改善 ,疏松透水 ,硬度下降 ,农田表涝现象得到缓解 ,效果持久稳定 ,连续 4年测定 ,耕翻一次后至第 4年其土壤硬度仍然明显低于常规耕作田块。 1996年～ 1998年大面积示范试验 ,使用该犁耕翻地块作物增产达 10 %～2 7.9%。该犁作业幅宽 5 0 cm,深度 6 0 cm,总牵引阻力 30～ 35 k N。更多还原

【Abstract】 Based on the field tests and the investigations, a three stage subsoil mixing plough, as a result of the international cooperation of China and Japan, was developed. This plough could meet the need for the improvement of Planosol solum by mixing the second (Aw) and Third (B) horizons, while leaving the first (Ap) horizon undisturbed. The mean soil mixing rate, M x was 0.7 and the mean transfer rate of the Aw to the B horizon, T Aw→B  was about 0.3. With the working width of 50 cm and the working depth of 60 cm, the total draught of the plough was about 30 kN under the normal field moisture condition. This draught requirement made the plough easily use in practice in China. In the field operated by the plough, good results for the soil physical properties were achieved. During the wet season, the excessive soil surface water could quickly penetrate into the subsoil. No recovery of soil hardness was observed after ploughing for four years, and hence the long term soil improvement was achieved. The yield increasing rate was 10%～27.9%, according to the large scale extension tests.更多还原