Impact of organic farming systems on runoff formation processes—A long-term sequential rainfall experiment

Nearly 50% of the agricultural used areas of the European Union can be classified as having a high or very high risk for soil surface sealing and erodibility. The objective of this long-term sequential experimental rainfall study was to identify the soil surface aggregation and crusting as well as runoff and infiltration effects of organic management systems (with different dates of conversion from conventional to organic farming) in comparison to a conventional management system. The experimental data received from the rainfall experiment showed that the soil surface crusting process started earlier in the conventionally managed soil than in the soils from the organic farm. Additionally the soil surface of the conventional and organic managed soils was similarly sealed, but the well-established organic farming management showed lower runoff than the recently established organic farming management. Both organic farming systems showed lower surface runoff and higher water infiltration capacity than the conventional management system. The conversion from conventional to organic farming resulted in lower soil surface runoff and higher infiltration which is a benefit of long-term organic farming systems to reduce erosion hazards and floods.