A Comprehensive Scientific Study on Hydraulic Conductivity in Sandy, Clayey, and Silty Soils With Reference to the USDA Soil Taxonomy Classification (2026)

Abstract

Hydraulic conductivity is one of the most important hydrophysical properties in soil science, as it determines the rate and volume of water flow through soil pores. This property is strongly influenced by soil particle-size composition (texture), internal structure, organic matter content, and degree of water saturation. Hydraulic conductivity values vary widely among different soil types: sandy soils record the highest values due to their large pore size, whereas clayey soils record the lowest values due to their fine particles and compaction. Silty soils occupy an intermediate position between the two. This study examines saturated and unsaturated hydraulic conductivity in sandy, clayey, and silty soils, reviews the American classification of these soils according to the USDA Soil Taxonomy system at the suborder level, reviews previous studies conducted on related soil properties in Libya, analyzes results derived from recent scientific studies, and concludes with practical recommendations of benefit to the agricultural, hydrological, and environmental sectors.