Estimation of influence of land use changes to flood outflows from affor-estation areas of the Roztocze Środkowe was worked out basing on SCS-CN meth-od. This method permits calculation from total rainfall a direct runoff as equivalent to effective rainfall. The original SCS-CN method in principle was worked out for catchments of cultivated areas [National Engineering Handbook 1956, 1985]. Present paper is focused on the idea of adaptation original method to forest con-ditions [Okoński 2006; Okoński, Miler 2010]. The main parameter of this method - CN is a function e.g. of land use. The empirical values of parameter CNemp were calculated basing on hydro-meteorological data of flood outflows at representative catchment of the Krynica River in the Roztocze Środkowe, in the area of the Tomaszów Lubelski Forest District, the Bełżec Forest Range. The dependence be-tween empirical value of parameter CNemp and his equivalent's value from original method is a basis idea of adaptation method SCS-CN to characteristics of investi-gated catchment. In consequence it gives then possibility to prognoses how the change of land use, e.g. forest stand reconstruction, afforestation, deforestation, change of field culture, significant change in infrastructure etc., will influence to flood outflows (change to water retention) at a ...
