In order to disentangle the causes of variations in water chemistry among European shallow lakes, we performed standardised sampling programs in 86 lakes along a latitudinal gradient from southern ...Spain to northern Sweden. Lakes with an area of 0.1 to 27 000 ha and mean depth of 0.45.6 m located in low to high altitudes were investigated within the EC project ECOFRAME 14 times during JuneOctober 20002001. Several variables like conductivity, alkalinity, abundance of submerged plants, concentrations of suspended solids, total nitrogen and phosphorus were latitude-dependent decreasing from south to north. Secchi depth, concentrations of total nitrogen, total phosphorus, suspended solids, and chlorophyll a correlated strongly with the presumed quality classes of the lakes.We came to the conclusion that the variability of shallow lakes in Europe is still mostly dependent on natural differences. Variables connected to lake morphometry, seasonality, basin geology and climate explained altogether nearly half of the total variability of lakes. The trophic state factor, describing mostly the human influence on lakes, was the strongest single factor responsible for nearly a quarter of the total variability of the studied European lakes.
In order to disentangle the causes of variations in water chemistry among European shallow lakes, we performed standardised sampling programs in 86 lakes along a latitudinal gradient from southern ...Spain to northern Sweden. Lakes with an area of 0.1 to 27 000 ha and mean depth of 0.4 5.6 m located in low to high altitudes were investigated within the EC project ECOFRAME 1 4 times during June October 2000 2001. Several variables like conductivity, alkalinity, abundance of submerged plants, concentrations of suspended solids, total nitrogen and phosphorus were latitude-dependent decreasing from south to north. Secchi depth, concentrations of total nitrogen, total phosphorus, suspended solids, and chlorophyll a correlated strongly with the presumed quality classes of the lakes.We came to the conclusion that the variability of shallow lakes in Europe is still mostly dependent on natural differences. Variables connected to lake morphometry, seasonality, basin geology and climate explained altogether nearly half of the total variability of lakes. The trophic state factor, describing mostly the human influence on lakes, was the strongest single factor responsible for nearly a quarter of the total variability of the studied European lakes.
The paper presents the quantity and quality (fractions) of dissolved organic carbon (DOC) in shallow ground waters of arable fields and littoral lake water and their seasonal changes. The study was ...conducted in the catchment of mesotrophic Piaseczno Lake in years 1992–1998. The samples of ground waters were taken from the observation well installed on the arable area about 15–20 m from the shoreline, on the border between the fields and the beach. Ground and lake water for analyses were taken in spring (IV, V), summer (VI, VII) and autumn (IX, X). In the water samples total dissolved organic carbon (DOC) and its fractions were determined. The fractions of DOC were the following: humus acids extracted in 0.5 mol NaOH dm-3, hemicelluloses dissolved in 0.5 mol H2SO4 dm-3 and fraction not yielding to extraction, i.e. residue. A program STATISTICA was used for statistical analyses. It was stated that the concentration of DOC and C of the humus acids in ground waters was significantly higher than in the lake waters. However, no differences were found between waters when percentage contribution of C in particular fractions to total DOC concentration was considered. In both kind of waters the contribution of humus acids amounted to about 60%, hemicelluloses to 7–8% and residue to 30% of DOC. Seasonal changes in the concentration of DOC and C of the fractions in waters were statistically not significant. However, a tendency for its higher values in autumn in comparison with summer and spring were observed. The results suggest that the ground waters from agricultural part of the catchment have influence on the state of dissolved organic carbon in the lake waters.
Influence of land-lake ecotone on mineral and organic compounds in groundwater and lake water Misztal, M. (Agricultural University, Lublin (Poland). Dept. of Hydrobiology and Ichthyobiology); Smal, H. (Ligeza, S.); Dyminska-Wydra, P. (Agricultural University, Lublin (Poland). Institute of Soil Science and Environment Management)
Polish journal of ecology,
(2003), Letnik:
51, Številka:
2
Journal Article
The aim of the present studies was to evaluate preliminary the influence of peatland, swamp, arable land and forest on the chemical composition and the organic matter of shallow ground water and the ...littoral lake water. The studies were carried out in the catchment areas of three lakes: the mesotrophic Lake Piaseczno, the eutrophic Lake Lukie, and the dystrophic Lake Moszne. It was found out that the ecotone ground water of all the studied objects showed higher mineralization and lower pH values than the respective littoral lake water
