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1

Microbial efficiency in a meromictic reservoir

Mazurkiewicz-Boroń G., Bednarz T., Wilk-Woźniak E.

Oceanological and Hydrobiological Studies

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2008

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Vol. 37, No.2

3-19

EN

Indices of microbial efficiency (expressed as oxygen consumption and carbon dioxide release) were determined in the water column of the meromictic Piaseczno Reservoir (in an opencast sulphur mine), which is rich in sulphur compounds. Phytoplankton abundances were low in both the mixolimnion (up to 15 m depth) and monimolimnion (below 15 m depth). In summer and winter, carbon dioxide release was 3-fold and 5-fold higher, respectively, in the monimolimnion than in the mixolimnion. Laboratory enrichments of the sulphur substrate of the water resulted in a decrease in oxygen consumption rate of by about 42% in mixolimnion samples, and in the carbon dioxide release rate by about 69% in monimolimnion samples. Water temperature, pH and bivalent ion contents were of major importance in shaping the microbial metabolic efficiency in the mixolimnion, whilst in the monimolimnion these elationships were not evident.

2

Mineralization of phycodetritus in water column of the submountain dam reservoir (southern Poland) : simulated experiments

Starzecka A., Bednarz T.

Polish Journal of Ecology

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2004

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Vol. 52, nr 3

247-259

EN

The mineralization (expressed as O2 consumption and CO2 release) of Scenedesmus quadricauda detritus was investigated in homothermal (spring, autumn) and stratified (summer, winter) conditions, using the Micro- Oxymax respirometer. In experiments, the rate of O2 consumption and CO2 release, sedimentation rate and time of mineralization of phycodetritus in water from 2.5, 7.5 and > 17 m depth were determined. It was found that 41% and 100% of detritus carbon (31.4 mg C dm^-3) added to the water could be mineralized in whole water column in time 28 days during spring and 37 days during autumn homothermal conditions. In summer stratification periods 61% of the detritus carbon during 29 days, and in winter 100% during 35 days, could be mineralised down to the depth 18 m. The rate of mineralization of phycodetritus depends on temperature and activity of microflora. The differences in the rate of O2 consumption and CO2 release between particular layers of water and seasons were statistically significant in the majority of cases.

3

Upper Vistula River : response of aquatic communities to pollution and impoundment. 7, Bioassay studies of water trophic state with Chlorella pyrenoidosa growth test

Bednarz T.

Polish Journal of Ecology

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2002

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Vol. 50, nr 2

191-200

EN

In the Upper Vistula River course three sections were distinguished: first, at 11 km of the river course, with low trophic level of water (mean yearly yield <30% of Chlorella pyrenoidosa Chick. control cultures), second, up to 66.2 km of the river course, with the moderate trophic level (between 30-50% yield of control), third below 115.6 km of the river course, with the high trophic level (between 50-80% of control yield). The highest water trophic level (80% of control cultures yield) was evidenced at 115.6 km of the river course, due to the input of industrial and municipal sewage. The yield of Chlorella cultures was highly significantly postively correlated with the content of organic matter, electrolytic conductivity, P-PO4, N (as N-NH4 + N-NO3), S-SO4, Ca and Mg concentration in the water. In case of Cd, Cu, Pb, Mn, Zn no correlation was found.

4

Upper Vistula River : response of aquatic communities to pollution and impoundment. 5, Photosynthetic and respiratory activity of seston

Starzecka A., Bednarz T.

Polish Journal of Ecology

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2002

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Vol. 50, nr 2

157-166

EN

From March 1997 to March 1998 the photosynthesis (PhS) and respiration of seston (Rs) and bacteria fraction (Rb) in the water of the Upper Vistula River on the section from 10.9 to 336.7 km of the river course were investigated. Methods applied: PhS - light and dark bottles, Rs - dark bottles, Rb - respiration of bacterial fraction, which was isolated by water filtration. The smallest mean yearly value of PhS (2.1-8.6 J dm^-3 24 h^-1) was found at 10.9 - 36.6 km of the river course and the greatest ones (40.4-42.7 J dm^-3 24 h^-1) at 248.2-336.7 km, in accordance with the size of the river. Rs was the smallest (23.9-28.7 J dm^-3 24 h^-1) between 10.9-45.7 km of the river course (on the rather clean sector) and decisively greater 51.6 J dm^-3 24 h^-1) at 115.6 km, at the most polluted sites. Along longitudinal profile of the Upper Vistula River Rb was equalized and ranged from 20.7 24.1 J dm^-3 24 h^-1, with the exception at 10.9 (spring clean part of the river, poor in seston) and 336.7 km of the river course, where it was 10-20% smaller. The last value might indicated the presence of organic matter easily avaiable to bacteria at this site. Rb constituted from 45 to 78% of seston Rs with the minimal value at 115.6 km of the river course (the most polluted) and its maximal participation at 10.9 km - clean part of the river, rather poor in seston.

5

Model of energy flow in the bottom sediments of littoral zone of a dam reservoir with regard to detritivorous roach, Rutilus rutilus (L.)

Starzecka A., Bednarz T., Amirowicz A.

Polish Journal of Ecology

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1999

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Vol. 47, no 1

103-112

EN

Data obtained from April to October 1995 (196 days) were used for work out the model of energy flow through the bottom sediments of littoral zone of Dobczyce Reservoir (southern Poland) with special regard to algae, bacteria and roach, Rutilus rutilus (L.) - dominating species in ichthyofauna of this reservoir. In the surface layer (0.5 cm) of bottom sediments ash free organic matter (2061-5534 kJ m^-2), biomass algae (88-357 kJ m^-2) and bacteria (0.26-6.69 kJ m^-2), primary (19.3-83.8 kJ m^-2 24 h^-1) and secondary production (0.4-185.9 kJ m^-2 24 h^-1), and respiration of epibenthic communities (124-297 kJ m^-2 24 h^-1) werw determined. The density of roach (mean values 5.6 g m^-2) and their daily food ration (4.6-60.8 J m^-2 24 h^-1) were also appointed. The data showed that the participation of roach in the pool of energy taken awey beyond the bottom was very small and equalled 0.01% of total pool of energy (40118 kJ m^-2 196 days^-1) released.

6

Microbiological processes taking place in Dobczyce reservoir during spring water bloom

Bednarz T., Starzecka A.

Oceanological Studies

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1998

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Vol. 27, No. 2

13-21

EN

In waters of Dobczyce reservoir, the organic carbon content, biomass of algae and bacteria, respiration of bacteria and respiration of aquatic organisms (measured by oxygen uptake), and energetic expenditures per unit of bacterial biomass ('costs of maintenance') at the beginning of spring water bloom (May, 1996) caused by Nitzschia palea (Kutz.) W. Sm. were greater than those in the second phase of bloom. However, photosynthesis of algae was greater in the second one. In the surface layer of bottom sediments, the greatest values of measured parameters were noted in the second phase of water bloom but the 'costs of maintenance' of bacteria reached maximum values one week after of water bloom break.