The effect of 12-year ecological farming on the soil hydraulic properties and repellency index.

The objective of this study was to elucidate the influence of long-term ecological farming on selected soil properties by comparing results obtained in the field with continuous conventional farming (CT) and those obtained in the field where the original CT was converted into ecological farming system with no-till practice (NT) twelve years earlier. Soil water retention curves were obtained for 100 cm3 undisturbed soil samples using a pressure plate apparatus. Hydraulic conductivity and the repellency index were assessed directly in the field using a mini disk infiltrometer. The examined soil properties showed that NT mostly had a positive influence on the soil quality. The soil water retention capacity represented by the saturated soil water content of 0.32 and 0.40 cm3 cm−3 and the reciprocal of the air-entry pressure head of 0.0227 and 0.0187 cm for CT and NT, respectively, was higher in the NT field than in the CT field. The soil physical quality, represented by the slope of the soil water retention curve at the inflection point of 0.033 (CT) and 0.047 (NT), was better under NT than CT. The hydraulic conductivity at the pressure head of –2 cm was higher in the NT field (0.97 cm hr.−1) than in the CT field (0.17 cm hr.−1). On the other hand, ecological farming increased water repellency (repellency index of 6.73 and 18.91 for CT and NT, respectively). [ABSTRACT FROM AUTHOR]