EN
In years 2007-2009 soil erosion measurements were conducted on plots and hillslopes with not separated area. The separated plots were closed by the Gerlach troughs with collectors. Measurements with not separated area were carried with the modified collectors of Słupik (entrance width 0,5 m). The aim of the paper is to compare the results and to evaluate the usefulness of the small collectors. Annual amounts of eroded soil occurred to be 12% smaller for cereals and 26% smaller for potatoes in comparison with erosion recorded in the separated plot. On a convex slope amounts of eroded material were higher (20% on average). On the other hand, the erosion on a concave slope was less effective (c. 35%) during any rainfall conditions. Mass of soil material collected in 10 collectors situated near each other was compared. It is calculated that measurement error due to the collector effectiveness and local differentiation of the geomorphic processes is ±6% if only two neighbouring collectors are considered and up to ±4% if tree catchers are taken into consideration. This error increase up to ±30% during small erosivity rainfalls (El₃₀< 20 MJ mm ha⁻¹h⁻¹).