The Effect of Density on Water Retention Properties of Field Soils

Summary The bulk density, available water ( A ν ), air capacity ( C α ), and retained water capacity (θ ν ) were determined for 158 A, B, and C horizons of field soils. Clay (< 2 μm) and silt (2=60 μm) were also determined. Statistical analysis of the results demonstrated that bulk density exerts a profound influence on A ν , C α , and θ ν , but the effect varies between texture groups and horizons. Significant negative correlations were obtained between bulk density and C α for most texture and horizon groups. In B and C horizons A ν and θ ν also decrease with increasing density, whereas in A horizons A ν and θ ν tend to increase with bulk density except in silty soils. Within a limited range it is feasible to control these parameters by using field techniques to achieve optimum bulk density for particular soils.