2022 年 32 巻 S 号 p. 107-111
The construction of shallow subsurface drainage (SSD) using a cut-soiler contributes to the mitigation of salinization in the field owing to the increased drainage efficiency. In this study, we investigated the effect of SSD construction on the crop yield and fluctuations of the soil water and solute contents, which were monitored using dielectric moisture/salinity sensors in a test field in India. We investigated four spacings (2.5, 5.0, 7.5, and 10 m) in which SSD was constructed at a depth of 60 cm, in addition to plots without SSD. After the construction, pearl millet and mustard were cultivated in the rainy season (July-October) and dry season (October-April), respectively. The results of yield surveys show that higher crop yields were obtained after the construction of SSD. According to the monitoring data during pearl millet cultivation, the porewater electrical conductivity (ECp) of the soil in the plots with 2.5 and 7.5 m spacings was lower than that of the soil without SSD. With these spacings, the increased ECp only decreased after rainfall and irrigation. Our results confirm that SSD decreases the soil salinity and increases the crop yield in salinized farmland.
