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Due to the recently increasing frequency of extreme changes in river runoff regime, scientific literature has dealt with the characteristics of runoff formation. Studies have been carried out on analyzing climate change and a lot of attention has fallen on land-use structures. Migration of precipitation through the river basin is influenced by the lithological composition of sediments. Its structure is determined by analyzing geological and geomorphological maps and by drilling boreholes in the selected area. With the help of boreholes the level of groundwater and lithological composition of sediments can be assessed. An installed system of lysimeters and piezometers in the borehole allows us to monitor the change of groundwater level and the amount of water moving through the unsaturated zone of sediments over time. The set of lysimeter boreholes allows us to capture and map the spacial change of these parameters. Following thorough analysis of the lithological structure of river basins in separate costal zones, this article aims at evaluating river runoff formation characteristics. The basin lithological factor was calculated based on large-scale maps using ArcGis software. In order to carry out more thorough analysis of the influence of lithology in given territories, sections of 0-50 m, 50-200 m, 200-500 m, 500-800 m, 800-1000 m, and >1000 m were established, calculating the distance in meters from the riverbank. Eight river basins of typical lithological structure (sandy, loamy, argillaceous) were selected and examined. The period of the year 1960-2013 was analyzed as this period and the relationship between the runoff and precipitation with correlation of 0.72-0.83 was established, as well as that with the lithological structure, established following the derivation of a hydromodule.
The article summarises results of studies conducted along the Baltic Sea sandy coasts by scientists involved in coastal dune research, and presents an attempt to describe the types and distribution of dune coasts. The Baltic Sea coasts feature lower and higher foredunes. The lowland behind the coastal dune belt is covered by wandering or stabilised inland dunes – transgressive forms, mainly parabolic or barchans. The source of sediment for dune development includes fluvioglacial sands from eroded coasts, river-discharged sand, and older eroded dunes. Due to the ongoing erosion and coastal retreat, many dunes have been eroded, and some are withdrawing onto the adjacent land. There are visible differences between the south-eastern, western, and northern parts of the Baltic Sea coast with respect to dune development. The entire southern and eastern coast abounds in sand, so the coastal dunes are large, formerly or currently wandering formations. The only shifting dunes are found at the Polish and the Russian–Lithuanian coasts on the Łebsko Lake Sandbar as well as on the Vistula and Curonian Spits. The very diverse shoreline of the south-western coast experiences a scarcity of larger sandy formations. Substantial parts of the Baltic Sea sandy coasts have been eroded or transformed by humans. The northern part of the Baltic Sea coast features mainly narrow and low sandy coasts (e.g. in Estonia). Further north, sandy dunes are virtually absent.
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