Water Retention and Repellency of a Sandy Soil Amended with Municipal Compost

The aim of this study was to investigate the influence of a drying process on sandy soil amended with different rates of compost on physical properties and with a special focus on soil water retention characteristics. The mixtures of compost and sandy soil with different compost rates were prepared, namely, 100% compost, 20% compost, 10% compost, and soil without compost. The samples were dried in the following temperatures: 20, 40, and 80 degrees C. The compost addition to the sandy soil led to an increase in soil porosity. Three pore fractions, bonding space, residual, and storage pores reached their highest values in the samples with higher compost rates. A reduction of residual and storage pores volume resulted in a decrease in available and productive water content. Lower compost content reduced the amount of stored water. The drying of the sandy soil amended with compost at rates of 100 and 20% triggered the water repellency effect.