Odnawialne złoża żwirów rzek Podhala
Abstract
INCREASE IN GRAVEL RESOURCES OF PODHALE RIVERS
Summary
In years 1961-1968 a process of natural renewal of gravel resources in perennially submerged heaps of gravels occurring along Czarny Dunajec and Białka streams was studied. The analysis primarily concerned two fractions, 15-25 cm and 25--40 cm, economically most important. No increase in amount of pebbles over 15 cm in size was found after the rises of the order of 50---60% of absolute maximum rise of water level (i.e. the highest rise ever recorded). Gravels of that fraction appeared on heaps of gravels not before the rises of the order of over 70% of absolute maximum rise passed by. Large granite pebbles over 25 cm in size were deposited only on heaps of gravels of Białka stream. Increase in resources of pebbles over 25 cm in size in years 1961-1968 was equal 1-2% of the amount occurring there before large-scale exploitation started.
Summary
In years 1961-1968 a process of natural renewal of gravel resources in perennially submerged heaps of gravels occurring along Czarny Dunajec and Białka streams was studied. The analysis primarily concerned two fractions, 15-25 cm and 25--40 cm, economically most important. No increase in amount of pebbles over 15 cm in size was found after the rises of the order of 50---60% of absolute maximum rise of water level (i.e. the highest rise ever recorded). Gravels of that fraction appeared on heaps of gravels not before the rises of the order of over 70% of absolute maximum rise passed by. Large granite pebbles over 25 cm in size were deposited only on heaps of gravels of Białka stream. Increase in resources of pebbles over 25 cm in size in years 1961-1968 was equal 1-2% of the amount occurring there before large-scale exploitation started.