Soil Permeability of Sandy Loam and Clay Loam Soil in the Paddy Fields in An Giang Province in Vietnam

Abstract

Permeability, essential for water retention, requires careful consideration in hydraulic engineering projects. Determining soil permeability is challenging due to spatial and temporal variability, complicating the application of classical formulas. In this context, a study investigating deep seepage was conducted on sandy loam and clay loam soils in Tri Ton and Phu Tan. This investigation involved quantifying the amount of water retained in the soil through laboratory cylinders and rice fields with water levels set at 5 cm and 10 cm. The findings of the research indicate a direct proportionality between the permeability coefficient and soil moisture in both soil types. Notably, porosity showed no discernible correlation with permeability coefficient at both 5 cm and 10 cm water levels for sandy loam soils, which restrict fluid flow despite the high pore volume and the permeability coefficient in sandy loam soil is K = 8.67 × 10−5 cm/s at 5 cm and 10 cm water levels, respectively K = 8.46 × 10−5 cm/s The infiltration of sandy loam was 4–5 times lower than laboratory rates at 5 cm and 10 cm water levels. While the permeability of clayey loam in rice fields was 0.6–2.2 times lower than laboratory values and the permeability coefficient at 5 cm and 10 cm water levels are K = 1.12 × 10−5 cm/s and K = 3.22 × 10−5 cm/s respectively. Furthermore, the infiltration equation for each treatment in rice fields for the two soil types was also built. The research suggests a robust connection between permeability and both porosity and moisture levels.

Keywords

• Sandy loam
• Clay loam
• Soil permeability
• Permeability coefficient
• The paddy fields