Limnol. Rev., Volume 11, Issue 2 (June 2011) – 5 articles , Pages 47-93

The aim of this study was to gather and summarize bathymetric measurements of Morskie Oko Lake which have been carried out up to now. Apart from the two existing plans from 1909 and 1934, a plan presenting the arrangement of isobaths in 1879 was worked out on the basis of numerical data. Moreover, after field investigation with an echo sounder in 2011, a new bathymetric plan was created. All four plans were used to calculate the basic morphometric parameters of Morskie Oko. Bathygraphic curves were determined from the volume of water found by measuring the areas between consecutive isobaths. The least accurate data come from 1879 while there is a considerable resemblance between the plans dated to 1934 and 2011. In case of the most recent plan, the measurements were for the first time related to the average, multi-annual (1963–2010) water level. Thus, the greatest depth found in 2011 can be regarded as the maximum depth. Further bathymetric studies could help to determine the rate of shallowing of Morskie Oko lake caused by weathered rock material, transported for instance by avalanches. Full article

The dominance of blue-green algae observed in many lakes is related to a high trophic level. Shallow eutrophic lakes are particularly often abundant in blue-green algae. The research on phytoplankton, the results of which are presented in this paper, was carried out between 2002 and 2005 in six lakes. These lakes differed considerably in their size and management methods applied in the catchment (drainage) area. A few types of water blooms were distinguished, which is related to the catchment area management, the intensity of mixing and the trophic level. Algal blooms of the Planktothrix type appeared in lakes situated in an open area of agricultural catchment basins. Algal blooms of the Limnothrix type were characteristic of lakes with a forest-agricultural catchment area but surrounded by high shores, which reduced the wind influence on the mixing. Sporadic mixed algal blooms were typical of lakes situated in forest catchment areas. Full article

Analysis was performed for lead content in the sediments of Lake Wigry (NE Poland), taking into account lithology, basic chemical component content and physical characteristics of sediment, Several hundred sediment samples from different parts of the lake and peatland around the lake, were collected. Their locations were determined by GPS and the depth of sediment by echosounder. The surface layer (0–10 cm) of sediment and sediment cores were taken to determine the spatial and vertical distribution of Pb. Concentrations of lead in the surface sediment range from 2.52 to 469 mg kg⁻¹. One of the most important factors influencing spatial distribution of Pb is sediment type. The highest content of Pb was found in samples of organic gyttja and the lowest in clastic sediment samples. Strong positive linear correlation (r = 0.7) between organic matter content and Pb concentration in sediment was observed. It may be the result of simple bio-accumulation of lead. A large influence of sediment location on Pb distribution was found. The largest concentration of this element was found in sediment of the Wigry Basin. The major part of Pb accumulates in the surface layer of sediment. Full article

Changes of nutrient concentrations in sediments and plant biomass as well as above-ground biomass production of four emergent macrophytes during the vegetation season were studied. Particularly, variations over time in N:P and N:K ratios in sediments between sites with and without vegetation as well as seasonally flooded and permanently flooded sites were investigated. In plant covered sites, biomass production and nutrient concentrations in the four wetland plant species were measured monthly from March to September 2008. The study was conducted in the littoral zone of the polymictic Lake Niepruszewskie. The performed analyses of N, P and K concentrations in plants and sediments indicated that measurements of nutrients in plant biomass better reflected nutrient availability for plant growth than analyses of nutrient contents in sediments. The vegetation biomass and nutrient concentrations in plant biomass in the shallow littoral zone were more sensitive to changes of water depth in comparison with the permanently flooded part of the littoral zone. The present study showed that the N:P biomass ratio was a better indicator of moisture changes than the N:K ratio or individual nutrients. Preferences of the studied macrophytes for nutrient concentrations in sediments depended more on the N:P ratio in the sediment than N or P or K concentrations individually. Glyceria maxima preferred sites with high N and K concentrations (N:K = 0.9) while Typha angustifolia occurred in sites with the lowest nutrient concentrations among the studied species (N:P and N:K = 0.1). Full article