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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.

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Upper Vistula River : response of aquatic communities to pollution and impoundment. 4, Chemical and bacteriological indices of water quality

Starzecka A.

Polish Journal of Ecology

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2002

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Vol. 50, nr 2

147-155

EN

The water quality and its changes in Upper Vistula River on the sector between 10.9 and 336.7 km of its course were carried out in annual cycle in the years 1997-1998. The classification of water comprised four classes of purity (I-IV) and based on the 5 biological and 5 chemical features of water. Particular classes were characterized by numerical taxonomic value of pollution (NTVP): 1.0-1.5 - class I, very pure water; 1.5-2.5 - class II, relatively pure water; 2.5-3.5 - class III, polluted water; 3.5-4.0 - class IV, very heavility polluted water. On the investigated section of the Vistula River three stretches might be distinguished: the first one between 10.9 and 66.2 km of the river course; the second from 115.6 to 248.2 km and the third at 336.7 km of the river course. On the basis of the mean annual values of biological and chemical features together, relatively pure water (II class purity) with NTVP ranging from 1.87 to 2.37 was noticed on the first investigated river stretch. The greatest pollution was shown on the second stretch, where NTVP ranged from 2.56 to 2.82 which corresponded to III class of water purity. On the third stretch the water was relatively pure (II class of purity) with NTVP 2.32.

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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.

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Upper Vistula River : response of aquatic communities to pollution and impoundment. 11, Research synthesis

Żurek R., Starzecka A., Bucka H.

Polish Journal of Ecology

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2002

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Vol. 50, nr 2

249-262

EN

Investigations on the Upper Vistula River course (from 11 to 337 km) in years 1997-1998 comprised: chemistry of water and sediments, indicators of water quality, such as bacteriological indices, metabolic activity of seston, phytoseston indicator taxa, algal growth test, zooseston assemblages, benthic diatom indices and occurrence of oligochaetes fauna. The pollution impact was reflected by distinct changes in chemistry of water and sediments, as well as by bacteriological indicators and alga growth test. No distinct changes have been noted in the structure of benthic diatom communities. Some improving tendency in the water quality was evident between 248-337 km of the river course,where the most tolerant to pollution taxa were partly replaced by less tolerant species. Some changes revealed an increase in numbers of beta-mesosaprobic and meso-eutraphentic Chlorococcales, which dominated over dense populations of cyanobacteria. Benthic animals assemblages indicated a decrease in pollution level between 248-337 km of the river course.In the case of zooseston no evident was oberved. The sector of the river received on 95 km high load of chlorides from coalmines until last site on 337 km. Load of chlorides was constant, whereas their concentrations diminished. Nitrate concentration arose together with loadings. Phosphate concentrations were constant similarly to loadings, excluding site at 337 km of the river course, where load arose. COD had similar pattern as chlorides. It seems to be better to operate on a greater number of specialised indices or parameters than mixed them into one, which might be confusing index.

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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.

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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.