Influence of compost amendment rate and level of compaction on the hydraulic functioning of soils

Abstract There has been widespread interest in using compost to improve the hydrologic functions of degraded soils at construction sites for reducing runoff and increasing infiltration. The objective this study was determine effects amendment rate on saturated hydraulic conductivity ( K s ) water retention order identify target rates enhancing soil functions. Samples were prepared with three textures (sandy loam, silt sandy clay loam), amended 0%, 10%, 20%, 30%, 40%, 50%. All tested a porosity 0.5 m 3 /m , loam further high (0.55 low (0.4 porosities. data then used model infiltration HYDRUS‐1D. With rate, mixtures generally increased medium level, more needed heavier soils. As decreased soil, amount rose from 20% Water distribution pore fractions (gravitational, plant‐available, unavailable water) depended texture, only highest plant‐available one soil. Results suggest texture should be taken into consideration when choosing achieve improvement goals. Hydrologic benefits may limited even if is compacted.