Soil Hydraulic Properties

These parameters are widely applied in the van Genuchten–Mualem soil water retention model, which describes the relationship between soil water content and matric potential. The dataset includes: θr (residual water content): The water content remaining in the soil after drying under high matric potential. θs (saturated water content): The maximum water content when all pores are filled with water. α (scaling parameter): The inverse matric potential at air-entry, related to the pressure at which large pores begin to drain. n (fitting parameter): A dimensionless parameter describing the shape of the soil water retention curve, linked to porosity and pore size distribution. m (shape factor): A parameter describing curve steepness, defined under Mualem’s restriction as m=1-1/n.

FC (field capacity): The water content at −33 kPa (330 cm), representing the upper limit of plant-available water. PWP (permanent wilting point): The water content at −1500 kPa (15,000 cm), representing the lower limit of plant-available water. AWC (available water content): The difference between field capacity and permanent wilting point (FC − PWP), indicating the volume of water available for plant uptake.