Oshurkevych O. The flow regulating influence of forests on small rivers catchments of Beskydy

Object of investigation hydrological functions of forests. Goal of work - to study the forest inventory characteristics on river catchments of different hierarchy level in Beskydy, to estimate their flow regulating role and its' change under forest harvesting. Research methods: forestry-hydrological, hydrological, forestry-inventory, soil, mathematical statistic. Science novelty: at first the optimal catchments area for management at which overcoming the quantity of forestland users rapidly grows have been determined by analyzing of the forestry enterprises structural units positioning with regard to the boundaries of catchments of various orders; the correlation dependences between water flow in main river and its' feeders with various forest land percentage have been established by experimental investigations; the flood regulation coefficient has been proposed and analyzed with purpose of its' use at estimation of the flow regulation forest influence; the tendency to flow regulating growth with increasing of forest land percentage and watershed area at precipitation of 70-80 mm has been analytically found; the mathematical models of flood flow versus catchments morphometric characteristics, inventory indices of forests on these river catchments and meteorological factors have been elaborated. Results: the obtained results will serve as theoretical and methodical base for introduction catchments principle in forestry management taking into account of forest flow regulating influence and its' change under forest harvesting works. Branch of application: forestry.