Studies on the Improvement of Soil-Overturning Performance by Rotary Tillage

本研究采用电导率法，利用KCl混合土估算旋耕法耕作土壤的位移比。主要结果如下：1。通过对耕前和耕后电导率的比较，确定了旋耕法前后土壤的位移。假设上切旋耕法的翻土性能优于下切旋耕法。随着耕作坡度的增加，下切式旋耕翻土效果恶化。2 .山中土壤硬度计指数为7 mm以下的土壤有减少土壤倾覆的趋势，硬度大于7 mm的土壤没有表现出土壤倾覆的差异。在42.4 mm耕距下，传统叶片的翻土性能优于曲线平缓的宽叶片。另一方面，在耕作间距为63.1 mm的情况下，两种叶片的翻土量几乎没有明显差异。砂土与粘壤土的试验结果对比表明，砂土比粘壤土的土壤翻倒效果好。然而，由于两种土壤的试验条件不同，我们不能肯定地得出这个结论。为了进一步简化上述方法使用的氯化钾混合土，我们进行了氯化钾溶液喷施新方法的基础试验。施用量变化幅度在4.1%以内。通过对氯化钾溶液渗透土壤电导率的测定，发现土壤电导率随土壤电导率的变化幅度为5.5%。然而，从各种结果来看，我们认为该方法有望作为判别土壤倾覆的方法。

In this study, the authors adopted electrical conductivity method used the mixture soil of KCl for the estimation of displacement ratio of soils tilled by rotary tillage. The main results were as follows.1. From the comparison of electrical conductivity before tillage with one after tillage, the soil displacement in the backward and forward by rotary tillage was confirmed. It is assumed that the soil-overturning performance of up-cut rotary tillage is better than one of down-cut rotary tillage. Moreover the soil-overturning by down-cut rotary deteriorated with the increase of tilling pitch.2. The soil under 7 mm with index number of Yamanaka soil hardness meter showed tendency to decrease the soil-overturning, but the soils above its hardness did not show the difference of soil overturning.3. In the tilling pitch of 42.4 mm, the soil-overturning performance by a traditional blade was better than a wide blade with gentle curve. On the other hand, the obvious difference for soil-overturning between both blades was not almost observed on the condition of tilling pitch 63.1 mm.4. Comparing the experimental results of sand with one of clay loam, soil-overturning of sand seems to be excellent than clay loam. However, we can not definitely conclude this, as the experimental condition differs between the two soils.5. In order to simplify furthermore the above method used mixture soil of KCl, we conducted a fundamental experiment of new method spraying the solution of KCl. The variation of application rate was within 4.1 %. Measuring the electrical conductivity of soil which solution of KCl percolated, the variation of 5.5 % in the swath width was recognized. However, From the various results, we think that this method is hopeful as the method to discriminate soil-overturning.