Wyniki wyszukiwania

1

Epiphytic fauna inhabiting Stratiotes aloides in a new lake of the Slowinski National Park (Smoldzinskie lake, Poland)

100%

Obolewski K., Strzelczak A.

International Journal of Ecohydrology and Hydrobiology

|

2009

|

tom 09

|

nr 2-4

2

MRandCT analysis of the qualitative and quantitative structure of macrozoobenthos in selected oxbow lakes of Northern Poland

100%

Obolewski K., Strzelczak A.

Oceanological and Hydrobiological Studies

|

2008

|

tom 37

|

nr 3

97-104

3

An attempt at modelling the periphyton dynamics with artificial neural networks exemplified by the oxbow lake reopening study (The Slupia River, Northern Poland

100%

Obolewski K., Strzelczak A.

Ecological Questions

|

2008

|

tom 10

An experiment was performed in the Osokowy Staw oxbow lake (the Słupia River, northern Poland). The old riverbed was reconnected with the riverine system and periphyton communities on nylon artificial substrate were surveyed before and after engineering works. Then, ANN (Artificial Neural Network) architectures were designed and trained in order to create models of interactions between 18 macrozooperiphyton, microzooperiphyton and phytoperiphyton taxa in the changing ecosystem. Calculations were performed using StatSoft Software Statistica 6.1 with the implemented neural network module.Neural network models allowed a quantitative insight into periphyton dynamics and indicated trophic relationships, both predatoryprey and competitive. Thus, we see ANN as a good technique for modelling multidimensional, nonlinear relations between epiphytic organisms and as a promising method for creating overall models.

4

Effects of a floodplain lake restoration on macroinvertebrate assemblages - a case study of the lowland river (the Slupia River , N Poland)

81%

Obolewski K., Glinska-Lewczuk K., Strzelczak A., Burandi P.

Polish Journal of Ecology

|

2014

|

tom 62

|

nr 3

A study on the response of macroinvertebrate assemblages to the restoration of hydrological connectivity of an oxbow lake through the channel excavation is presented. The study included a five-year environmental monitoring (hydrological, hydro-chemical measurements and invertebrate sampling) carried out in the years 2008–2009 and 2011–2012 in the floodplain of the Słupia River (N Poland). The results allowed for assessing ecological effects of the hydrotechnical treatments (re-opening of an old river bed, declogging and installation of wooden deflectors) applied in the oxbow restoration. The results confirmed the preliminary hypothesis that the level of hydrological connectivity determines the dynamics of invertebrate fauna communities in river-floodplain systems. Analysis of the data revealed that such reconnection considerably influenced the structure of hydrobionts by altering abiotic habitat conditions. Effects of radical changes in the habitat morphology and hydrodynamic conditions and monitoring of macroinvertebrate assemblages preformed in the restored lake indicated a significant instability of the ecosystem soon after the treatment, what was confirmed by the results of canonical analysis, in which 50% of the total variance remained unexplained. Among factors analysed, water quality parameters explained 21.4% of the total variance in macroinvertebrate communities. However, the hydrobionts showed a significant instability with respect to variable hydrological conditions (flow through the lake) what contributed to a low share of water flow along the oxbow in explaining the total variance. The analysis of long-term changes that occurred in the studied ecosystem showed that the restoration of full hydrological connectivity brought only a short-term increase in benthofauna abundance. The most distinct reorganization in the structure of macroinvertebrate communities was observed in the first year after the reconnection while the consecutive four years brought only insignificant changes, mainly the appearance of a few species, mainly molluscs. Our investigation suggests that the taxonomic composition of macroinvertebrates in the studied oxbow lake having the only one-arm opening, before the improvement of hydrological connectivity, seemed to be more stable and optimal for this kind of habitat, than after the hydrotechnical works, when the ecosystem became passable due to both-arms connections to the river channel. Therefore, semi-lotic oxbows, connected to parent rivers only with one arm, can be properly functioning aquatic ecosystems in river floodplains.

5

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Distribution of common bivalves in the Polish coastal zone of the Baltic Sea

81%

Piesik Z., Obolewski K., Strzelczak A.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

|

2009

|

tom 13 part II

The populations of common Baltic bivalves Macoma balthica, Mytilus edulis and Cerastoderma glaucum were studied in the Polish coast (up to 4 Nm), both in estuary and open coastal zones of the Middle Pomerania as well as in the Puck Bay and the Gulf of Gdańsk (up to 2 Nm). The following parameters were investigated: density of the bivalves and environmental conditions (distance from the shore, substrate type, coast type, depth). Relationships between environmental conditions and abundance of the consecutive bivalve species were analysed with the help of ordination method (redundancy analysis RDA) and multivariate regression trees (MRT). RDA analysis indicated that C. glaucum density depended mainly on the localisation along the coast while M. edulis occurrence was governed by the distance from the shore and depth. Only density of M. balthica depended evenly on all the environmental parameters. MRT analysis revealed that the main factors influencing the distribution of bivalves were sediment granularity and depth.

6

Seasonal variation of Ganoderma spore concentrations in urban and suburban districts of the city of Szczecin, Poland

81%

Grinn-Gofron A., Strzelczak A., Przestrzelska K.

Annals of Agricultural and Environmental Medicine

|

2015

|

tom 22

|

nr 1

7

Present-day evolution of coastal lakes based on the example of Jamno and Bukowo (the Southern Baltic coast)

81%

Choinski A., Ptak M., Strzelczak A.

Oceanological and Hydrobiological Studies

|

2014

|

tom 43

|

nr 2

8

Quantitative structure of Hediste diversicolor (O. F. Muller) in estuary zones of the southern Baltic Sea (Poland's central coastline)

81%

Obolewski K., Strzelczak A., Bodo K.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

|

2009

|

tom 13 part I

This study concerns the distribution of nereid Hediste diversicolor in the Middle Pomerania, near the estuaries of five rivers (Parsęta, Wieprza, Słupia, Łupawa and Łeba). The highest density of Hediste was observed in the vicinity of the Wieprza estuary while the lowest (7-fold lower) in the estuary of the Łeba River. As for biomass, it was the highest in the river mouth of Parsęta and the lowest in the Wieprza estuary. Frequency in the studied estuaries was low and amounted to 32%. Using standard statistical methods (significance tests) we indicated differences in average Hediste density and biomass between the eastern and western transects. Nereid’s density was 2-fold higher in the eastern transects while biomass in western. The applied multivariate regression and classification tree method (MR&CT) revealed that the density of Hediste was determined only by the depth of a sampling site while biomass by the distance from the coast. The Spearman’s correlation coefficient analysis indicated significant (p < 0.05) dependence of biomass and density on depth and distance from the shore. Due to ecological role of H.diversicolor as a food source for benthivorous fish, including valuable and endangered species (cod, flatfish), the analysis of food supply can be important in the identification of fish feeding grounds.

9

Changeability of accumulated heat content in alpine-type lakes

81%

Choinski A., Ptak M., Strzelczak A.

Polish Journal of Environmental Studies

|

2015

|

tom 24

|

nr 6

10

Disappearance of lake Jelenino since the end of the XVIII century as an effect of anthropogenic transformations of the natural environment

81%

Ptak M., Choinski A., Strzelczak A., Targosz A.

Polish Journal of Environmental Studies

|

2013

|

tom 22

|

nr 1

This study presents the contribution of reclamation works to the disappearance of Lake Jelenino. On the basis of cartographic materials from the 19th and 20th centuries, as well as historical records, it was possible to establish that the lake of area 495.2 ha disappeared as a result of precise actions aimed at creating new settlements. Reclamation works proceeded in two stages. After the first stage, which took place in 1778-86, the area of Lake Jelenino was reduced by over 360 ha. In the 1970s the reservoir, whose area then amounted to 130 ha, was completely dried. Such a transformation of the natural environment was followed by social and economic changes – inhabitants of Jelenino village, who until then lived by fishing, in a short period of time retrained for agriculture and breeding.

11

Influence of anthropogenic factors on microhabitats inhabited by riverine hydrobionts - assessment with MRT method

81%

Osadowski Z., Obolewski K., Strzelczak A.

Ecological Questions

|

2008

|

tom 10

This study concerns the influence of urban area on vegetation and invertebrates inhabiting the Słupia River (northern Poland). Altogether, 10 plant communities and 37 macrozoobenthos taxa were determined during four seasonal samplings (October 2005, January, April and August 2006). In order to reveal how the city of Słupsk affects the vegetation and fauna, MRT (multivariate regression tree) models were created. On their basis the most important factors were determined from the following set of variables: season, water temperature, salinity, distance, water depth, bottom type, location in the river bed and degree of river bed transformations. Performed analyses showed that vegetation in the urban area was primarily influenced by distance (correlated with anthropogenic pressure), while for invertebrates season and temperature were the most important factors.

12

Distribution and the role of Cerastoderma glaucum (Poiret, 1789) in the Polish Baltic Sea coast

81%

Obolewski K., Konkel M., Strzelczak A., Piesik Z.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

|

2007

|

tom 11

A population of Cerastoderma glaucum Poiret 1789 was studied in the Polish coastal zone (up to 3 Nautical miles) of the Baltic Sea within the Puck Bay and part of the Gulf of Gdańsk. The frequency (F) in the sheltered coastal zone of bays was high (65%), whereas at the exposed open coast of the Middle Pomerania it was lower (43%). Also, abundance in the Puck Bay and the Gulf of Gdańsk was over 3-fold higher than in the coastal zone of the Middle Pomerania. By means of classic statistical methods (essential tests) we proved the significance of differences between mean abundance at west and east transects in estuaries and between open coast and estuaries. The multivariate regression and classification trees (MR&CT) indicated that biomass and abundance of C. glaucum in the Baltic Sea were affected by the kind of bottom, whereas depth and distance to the bank influenced cockles' abundance and biomass in bays. The population's structure in the Puck Bay and the Gulf of Gdańsk was determined mainly by the depth. In the Wieprza River estuary only specimens from age group 1+ were found. On all the other studied profiles cockles lived up to 3 or 4 years and the dominant group was 2+. The highest mean width of shell was in the Słupia River estuary, and in the bays shell width increased from west to east. In comparison to the other bivalves inhabiting the discussed area, C. glaucum does not play an important role as food source for fish and other consumers but may serve as an indicator of environmental conditions.

13

Chemical composition of reed Phragmites australis [Cav.] Trin. ex Steud. versus density and structure of periphyton in various aquatic ecosystem

80%

Obolewski K., Strzelczak A., Kiepas-Kokot A.

Journal of Elementology

|

2007

|

tom 12

|

nr 1

Analyses of three macroelements and six microelements in reed stems, accompanied by investigation of periphyton density were carried out in two reservoirs: Żarnowieckie Lake and Puck Bay. To reveal the influence of chemical composition of biotic substrate on periphyton qualitative and quantitative characteristics, ordination methods were applied (PCA, CCA, DCA, RDA). The results indicated that Copoepoda (Harpacticoida) and Chlorophyta preferred reed substrate with relatively high zinc, sulfur and chromium but low manganese and carbon content. In turn, Nematoda reached the highest density on a substrate rich in manganese. Mercury in reed limited density of Arachnidae-Hydrachnella and Chironomidae larvae, an effect which was not observed for Ciliata libera. Copepoda (Harpacticoida) preferred low chromium and lead content and high carbon/nitrogen ratio, which meant low nitrogen concentration in the reed substrate. Moreover, preferences of Nematoda and Bacillariophyta for freshwaters and Copepoda for brackish waters were indicated. The results presented in this paper should be treated as a contribution to more detailed research on interactions between reed chemical composition and periphyton density.

Ograniczanie wyników

Epiphytic fauna inhabiting Stratiotes aloides in a new lake of the Slowinski National Park (Smoldzinskie lake, Poland)

MRandCT analysis of the qualitative and quantitative structure of macrozoobenthos in selected oxbow lakes of Northern Poland

An attempt at modelling the periphyton dynamics with artificial neural networks exemplified by the oxbow lake reopening study (The Slupia River, Northern Poland

Effects of a floodplain lake restoration on macroinvertebrate assemblages - a case study of the lowland river (the Slupia River , N Poland)

Distribution of common bivalves in the Polish coastal zone of the Baltic Sea

Seasonal variation of Ganoderma spore concentrations in urban and suburban districts of the city of Szczecin, Poland

Present-day evolution of coastal lakes based on the example of Jamno and Bukowo (the Southern Baltic coast)

Quantitative structure of Hediste diversicolor (O. F. Muller) in estuary zones of the southern Baltic Sea (Poland's central coastline)

Changeability of accumulated heat content in alpine-type lakes

Disappearance of lake Jelenino since the end of the XVIII century as an effect of anthropogenic transformations of the natural environment

Influence of anthropogenic factors on microhabitats inhabited by riverine hydrobionts - assessment with MRT method

Distribution and the role of Cerastoderma glaucum (Poiret, 1789) in the Polish Baltic Sea coast

Chemical composition of reed Phragmites australis [Cav.] Trin. ex Steud. versus density and structure of periphyton in various aquatic ecosystem