Spływ wody i erozja gleby na piaszczystym stoku w obszarze młodoglacjalnym – pomiary poletkowe (Pojezierze Suwalskie, Polska NE)

The aim of the study performed in years 2007-2009 in the Suwałki Lakeland was assessed the intensity of soil erosion and runoff on a sandy slope under different cultivation. The study also focused on analysis of selected factors affecting the erosion (intensity of rainfalls, erosion susceptibility of soil, vegetation cover). Measurements were performed on the standard USLE plots inclined 8°. The mean annual erosion amounted to 0,2 t ha⁻¹ under cereals (rye and oat), 2,1 t ha⁻¹ under potatoes planted in rows parallel to the slope gradient, and 2,75 t ha⁻¹ on the black fallow. Experimentally determined index of erosion susceptibility K was 0,0041. The mean annual value of the canopy factor C was 0,064 for cereals and 0,8 for potatoes. Short rainfall events of 20-30mm and erosivity 100-200 MJ mm ha⁻¹h⁻¹ are characteristic for the study area. The results obtained for the sandy slope support previous findings that such short-term events play a significant role in soil erosion. Effectivity of such events strongly depends on the vegetation cover as they are responsible for 25-30% of soil loss under potatoes and 45-50% under cereals.