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Non-pollen palynomorphs characteristic for the dystrophic stage of humic lakes in the Wigry National Park, NE Poland

Fiłoc M., Kupryjanowicz M.

Studia Quaternaria

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2015

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Vol. 32, Nr 1

31--41

EN

The numerous dystrophic (humic) lakes are a very important feature of Wigry National Park, NE Poland. As the most recent palaeoecological data indicate, at the beginning of its development (in the Late Glacial and Early and Middle Holocene) these water bodies functioned as harmonious lakes, and their transformation into dystrophic lakes and the stabilization of the trophic state took place at the beginning of the Subboreal. Palynological analysis of sediments from two such lakes (Lake Ślepe and Lake Suchar II), with special emphasis on non-pollen palynomorphs (NPPs), was aimed at a detailed biological characterization of dystrophic lakes during their long-lasting existence. The obtained results allowed for the designation of organisms characteristic for dystrophic lakes, of which representatives appeared with the decreasing pH of the water and the formation of Sphagnum peat around lakes. These organisms were divided into four groups: algae, fungi, testate amoebas, and animals. Their representatives appear in various developmental stages of dystrophic lakes.

2

Biogeochemical functioning of hydrologically modified peatlands and its effect in eutrophication of freshwaters

Kruk M.

Polish Journal of Ecology

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2000

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Vol. 48, nr 2

103-161

EN

It has been found that, except for trace metals (Zn, Cu, Pb and Cd), peatlands having been hydrologically modified as a result of various anthropogenic activities do not play a barrier role for mineral elements incoming from the catchments and the atmosphere. In contrast, they may be a source of P compounds that additionally supply aquatic ecosystems. With use of multiple regression it has been revealed that eutrophication of peatlands and stream waters is favoured primarily by influks of biogenic elements from the catchments, dynamics of water storage by the peatland, amount and pH of precipitation, as well as by influence of numerous modifying ions. On a landscape scale, hydrologic changes of forest watersheds with peatlands, as well as deforestation and reduction of acreage of peat meadows in relation to arable lands are reasons of biogeochemical transformations of the lakeland landscape. Overall, these factors increase matter transfer from terrestrial to aquatic ecosystems.

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Long term effects of liming in a humic lake : ecosystem processes, biodiversity, food web functioning (Lake Flosek, Masurian Lakeland, Poland)

Hillbricht-Ilkowska A., Dusoge K., Ejsmont-Karabin J., Jasser I., Kufel I., Ozimek T., Rybak J.I., Rzepecki M., Węgleńska T.

Polish Journal of Ecology

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1998

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Vol. 46, no 4

347-415

EN

The chemical composition of water and bottom sediments, productivity and decomposition rates as well as the biodiversity and food web functioning (organic suspension, edible algae, bacterio-detrivores, herbivores, grazers, predators) in plankton and benthos were analysed in humuc, weakly acid, mid-forest lake surrounded by peatmoss Sphagnum (Lake Flosek, Masurian Lakeland, Poland) before and 1-4 and 20-23 years after application of powdered lime. Calcium content and pH in water and sediment raised permanently. High water quality variables were main-tained after liming (low production, algal biomass, chlorophyll and nutrient concentration, low release rate of phosphorus from the sediments). Decomposition rate of organic matter increased significantly. The species richness and diversity of algae, rotifers, crustacean and benthic invertebrates increased at least twice as well as the abundance of bacterio-detrivores in plankton (small rotifers) and benthos (chironomids) and herbivores (big daphnids, diaptomids) in plankton. The distinct succession in species composition was observed in many taxa. The predators like larvae of Chaoborus, cyclopids and predatory rotifers became very abundant after 20 years since liming. No evident peatmoss mat spreading over the lake table has been observed since liming but also no detrimental effect on peatmoss surrounding the lake. It was concluded that the moderate liming affects first of all the biodiversity of lake biota then it stimulates the mobilisation of the lake which eventually lead to the greater and more stable complexity of trophic links. The species-rich and top-down controlled food web was installed in the limed lake without interfering with high quality of lake waters (low-productive, high-transparent) and unique, natural values of its surroundings.However, a slight increase in nutrient concentration after 22-23 years was observed which could be related to more efficient recycling mechanism in lake (due to abundant big components in plankton and benthos) or to eutrophication.

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Algal communities of humic acid sites: biomass and diversity in lake water versus peat-mat water

Luścińska M., Soska R.

Polish Journal of Ecology

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1998

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Vol. 46, no 2

123-135

EN

In the water of a humic lake, and in the peat-bog surrounding it, there were recorded 70 taxa of algae: Cyanophyta, Pyrrophyta, Cryptophyta, Chrysophyta, Euglenophyta and Chlorophyta. In the peat-bog water a higher variety of species and algal biomass was observed than in the lake water. The relatively low biomass of algae in the lake water, was produced by few nanoplanktonic species, i.e. mixotrophic flagellates from Cryptophyta, Pyrrophyta and Chrysophyta.The comparatively higher biomass was formed by peat-bog algae, both in the nearest neighbourhood of the lake and in the bog pine forest. Community of algae from the peat-bog differs also according to the distance from the lake.