Soil-Water Dynamics Pattern in a Lettuce Cropping Field under Various Mulches Coverage

Abstract

Soil-water dynamics pattern in a lettuce cropping field under cotton mulch (CM), plastic mulch (PM), and zero mulch (C) coverage was characterized. Three lettuce plots of 300 cm x 100 cm large each were prepared. Soil-water content, electrical conductivity (EC) and temperature at 0-10 and 10-20 cm depth were monitored hourly. Soil-hydraulic conductivity (K us ) within each soil profile was characterized and modelled using van-Genuchten model. The soil with CM showed higher water content (0.29-0.33 cm 3 cm −3 ) than that with PM (0.29-0.31 cm 3 cm −3 ) and C (0.26 cm 3 cm −3 ). At 32.1 mm d −1 rainfall rate, the soil EC with CM (0.22-0.30 dS m −1 ) was higher than others (< 0.02 dS m −1 ). The soil temperature with CM was 2-3 and 4-5 °C lower than that with PM and C, respectively. Furthermore, the CM plot had higher K us (3.1-4.4 cm d −1 ) compared to the PM (0.18-0.21 cm d −1 ) and C plot (0.36 cm d −1 ). The results reflect a unique characteristic of the cotton mulch, which is able to provide sufficient water and nutrient availability, and to control weeds and temperature in soil profile, for effective growth as well as sustainable production of the crop.