Wpływ eksploatacji na rozmieszczenie żwirów w kamieńcach Czarnego Dunajca i Białki

Abstract

INFLUENCE OF EXPLOITATION UPON DISTRIBUTION OF GRAVELS IN THE CZARNY DUNAJEC AND THE BIAŁKA RIVERSSummaryIn the years 1955-1964 a selective exploitation of gravels took place on a large scale in the rivers of the Podhale area. Granite gravels 25-40 m. in diameter were mostly exploited there. Up to 1954, pebbles of this size were found in the Czamy Dunajec River along a sector from Siwa Polana to Wróblówka, and along the whole length of the Białka River. However, during 1955-1964, due to an intense exploitation, the pebbles were almost completely removed from numerous places of the shallow river bottom. In 1960, along certain sectors of both rivers the exploitation of gravels was stopped. At present, on the shallow bottom there rests here gravel amounting to 5-15 m. in size only. From 1961 to 1964, after several high water waves (one great and some smaller water rises) no pebbles greater than those left here after exploitation, were found along the sectors considered. Large pebbles encountered on the shallow river bottom after a water rise are single specimens only, and come from the edge of the eroded terrace.