Studies on Effect of Soil Conditioners (Part 4) : Reformation of Leaky Paddy Field

Abstract

Four synthetic soil conditioners (VAMA, NPAN, CMC, PVA) were put in the middle layer of soil in the lysimeter 1 lb. in weight. The lysimeters were irrigated, and the drainage in them were estimated continuously for 60 days. 1. VAMA and HPAN were most effective to prevent the soil from its leaking perfectly, when used 2 g per 40 cm^2. (Fig. 2〜3) 2. CMC was less effective than VAMA, and PVA could not lessen leaking. (Fig. 4〜5) 3. Ca(OH)_2,CaCO_3,Al_2(SO_4)_3,FeCl_3 and two sufactants were applied. But no influence of these materials was on the preventing effect of conditioners. (Fig. 6〜8) 4. Soil conditioners were put in the upper parts of soils, and their preventing effect on leaking were observed. But, in this case, they were less effective than in the case when they were spread in a thin layer. 5. The soil was mixed with conditioners, dried at 40〜50℃, and then, irrigated. But, in this case the preventing effect of conditioners on leaking was not observed.