Wskaźnik średniej rocznej erozyjności deszczu i spływu powierzchniowego (R) na przykładzie stacji meteorologicznej w Łazach k. Bochni (region klimatu Pogórza Karpackiego)

: Rainfall and runoff erosivity factor (R) is a key input parameter to the USLE (Universal Soil Loss Equation) and many other models (RUSLE – Revised Universal Soil Loss Equation, USPED – Unit Stream Power based Erosion/Deposition) There is still no precise characteristic of rainfall erosivity in Poland Local R factor values, according to Wischmeier and Smith procedure (1965, 1978) were calculated only for 13 meteorological stations The main aim of the paper is to estimate rainfall and runoff erosivity factor (R) for the Carpathian Foothills climatic region on the basis of 1987–2008 rainfall data for Łazy near Bochnia meteorological station (Wiśnicz Foothills) The average rainfall and runoff factor (R) for Łazy calculated for the years 1987–2008 equalled 106 6 MJ cm ha –1 h –1 This value was bigger in comparison with the values for other locations in western (Wrocław-Swojec), northern (Elbląg) northeastern (Suwałki) or central Poland (Otwock, Sandomierz, Puczniew) and similar to the values for the Carpathians (Lesko, Lima- nowa, Szymbark) The annual values of R factor for Łazy ranged between 27 7 in 1993 and 455 9 MJ cm ha –1 h –1 in 2006 Maximum monthly values of rainfall factor R r in a year varied from 6 1 in July (1993) to 428 7 MJ cm ha –1 h –1 in June (2006) The most intensive potential soil erosion by water due to erosivity of rains is likely to happen in June, July, May and August