The paper considers whether in recent years there have been changes in the structure of the water circulation in Lake Wigry, the main water body of the Wigry National Park. The volume and trends in the streams of water exchange in the lake have been assessed. They show that in recent years the horizontal water exchange is being reduced as the inflow to the lake is growing, mainly due to its main tributary, the Czarna Hańcza, while the outflow from the lake is decreasing. The paper examines whether these changes are reflected in the structure of the lake water circulation, which has been assessed on the basis of the lake water balance
The aim of the study was to locate and describe groundwater outflows in a selected lake basin. The study hypothesis was based on the fact that, according to the specialist literature, one of the forms of lake water supply is through groundwater outflows. It was also assumed that the lakes of the Kashubian Lake District are characterised by such a form of lake water supply. The time scope of the work included the period from January 2011 to September 2012. The spatial scope of the work included the area of Lake Raduńskie Górne, located in the Kashubian Lake District in north Poland. The research plot was in the north-eastern part of the lake. Office works were aimed at gathering and studying source materials and maps. Cartographic materials were analysed with the use of the MapInfo Professional 9.5. The purpose of the field work was to find the groundwater outflows in the basin of Lake Raduńskie Górne. During the field research diving was carried out in the lake. During the dive audiovisual documentation was conducted using a Nikon D90 camera with Ikelite underwater housing for Nikon D90 and an Ikelite DS 161 movie substrobe, as well as a GoPro HD HERO 2 Outdoor camera. During the project, four groundwater outflows were found. In order to examine these springs audiovisual and photographic documentation was made. To systematise the typology of the discovered springs, new nomenclature was suggested, namely under-lake springs with subtypes: an under-lake slope spring and under-lake offshore spring
In the paper it is shown that the lakes of the North-Eastern Poland fulfil various functions in the groundwater phase of the water circulation. The value of the resultant of the groundwater supply to the lake, and in some cases also its direction, depend on the volume of the water undergoing a total exchange in the reservoir in the given year. In through-flow lakes the runoff increase coefficient also influences this value.
Balance Models for Water Resources Investigations, Water Resour.Manag.12(1): 20–50.
Yin X., Nicholson S.E., 1998, The water balance of Lake Victoria, Hydrol.Sci. J. 43(5): 789–811.
Zhang Z., Huang Y., Xu C.Y., Chen X., Moss E.M., Jin Q., Bailey A.M., 2016, Analysis of Poyang Lakewaterbalance and its indication of a river–lake interaction, SpringerPlus 5(1): 1555.
-Turek [Changes in the surface and ground water balance in the Konin brown-coal mining area. In: Changes in the natural environment of the Konin-Turk area]. Ed. W. Stankowski. Poznań. Wydaw. Nauk. UAM p. 153–163.
R ösler A., B ielawny K., C hmal M., C hmal T., S taszkiewicz S., S zymanowska K. 2007. Analiza zmian składowych bilansu wodnego jezior na przykładzie jeziora Sława (1976–2005) [Analysis of changes in the components of lakewaterbalance on the example of Sława Lake (1976–2005)]. Report on the research task of DS. – H 1.6b. Poznań. IMGW pp. 24.