Water Infiltration into Sand, Silt, and Clay at Field Capacity

Abstract

Field capacity (FC), permanent wilting (PWP), and plant available water (PAW) are essential parameters to estimate for soils because they are essential for water irrigation management. However, these parameters were reported in water volume per unit soil volume. Knowing the soil required water volume does not imply immediate water availability, that is, the speed at which the water could be supplied to the soil. This is because there is a lag time between water irrigation initiation and the water increment in the soil depth. This study uses the field capacity’s soil water content to simulate the water infiltration using Richards’ equation. The studied soil medium was silt, sand, and clay. The study allows an estimate of water infiltration time and infiltrated water to relate to the soil depth of interest. The clayey has the highest FC, and the silty soil has the highest PAW. The results revealed silty soil could contain more readily water for plant growth than sand and clay. This study also revealed silty soil to be a better soil medium than sand and clay. It has the best tradeoff between water infiltration time and the infiltrated amount of water for plant absorption. This study’s coupling technique will be a useful tool for farmers and field practitioners to assess any site based on the soil texture at an early stage of water irrigation investigation.