human impact, stream, Moravskoslezské Beskydy

Mountain streams are integral and sensitive part of fluvial net, which are generally perceived as relatively unimpacted by man activities compared to streams located in lowland urbanised areas. However, this perception is somehow contradicted by long-term anthropogenic pressure on the valleys of the most of European mountain ranges. Our contribution summarises five hundred years of human effects on mountain streams by using the example of the Moravskoslezské Beskydy Mts. (Western Carpathians). Deforestation since the beginning of Wallachian colonisation (16th century) likely together with climatic oscillations accelerated sediment supply from adjacent hillslopes consisted of well erodible flysch lithology into local channels, which in turn influenced deposition-erosion cycles in the valleys. The present dense canopy of heavily managed forests decreases not only the intensity of hillslope-channel coupling, but regular timber harvesting also limits recruitment of large wood into streams as important components driving longitudinal sediment fluxes and in-channel geomorphic and hydraulic processes.