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1

Time of Chironomus plumosus [L.] generations in natural conditions of lowland reservoir

100%
Kajak Z., Prus P.
Polish Journal of Ecology
|
2004
|
tom 52
|
nr 2
The time of Chironomus plu- mosus generation in the field conditions (shallow, eutrophic dam reservoir) was estimated to be about 3 weeks in the spring. This estimate has been possible due to simultaneous mass appearance of young larvae (the new generation) and the lack of older larvae at this time. Later in the season usually there was some amount of the youngest larvae, indicating the permanent emergence of imagos and the egg-laying, but without clear peaks of numbers and boundaries between successive generations. This regularity and the relatively low total numbers of larvae during the summer indicate the heavy fish pressure on the benthos, not allowing for the mass appearance of young larvae and the estimate of the generation time. Fish pressure is probably weak in spring, during a spawning period, but then increase in the summer. The generation number could be theoretically as high as 5 during the vegetation season (May–October), assuming about 3 weeks for full larval development, as it was estimated at optimal feeding and oxygen conditions and low fish pressure in the spring. However some limiting factors like: oxygen deficits, the annoyance by fish and bestrewing of larval tubes with the mud transported by the water flow (range 150–500 m³ s⁻¹ of the total inflow) increase in the summer. These factors can slow down larval development, resulting in observed lower generation number: 3 to 4 during a year.
2

Riverine water transformation during retention in small lowland reservoirs

84%
Suchowolec T., Gorniak A.
Oceanological and Hydrobiological Studies
|
2009
|
tom 38
|
nr 4
103-108
3

The influence of wind on cyanobacterial bloom development in shallow, lowland reservoir in central Poland

84%
Izydorczyk K., Tarczynska M.
International Journal of Ecohydrology and Hydrobiology
|
2005
|
tom 05
|
nr 3
195-203
4

The role of a eutrophic lowland reservoir in shaping the composition of river phytoplankton

84%
Grabowska M.
International Journal of Ecohydrology and Hydrobiology
|
2012
|
tom 12
|
nr 3
5

Year-to-year stability of aggregations of Viviparus viviparus [Linnaeus 1758] in littoral zone of lowland, rheophilic reservoir [Central Poland]

84%
Jakubik B.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 1
The aggregations of V. viviparus were observed in the littoral of Zegrzyński Reservoir (Central Poland), and in the outfalls of its tributaries. They were present over five years of studies (1990-1994), at the same sites. The densities of snails in the aggregations differed among the sites (from over 800 to 500 ind. m⁻² in the reservoir itself), and showed seasonal changes with maximum in summer, and minimum in spring and fall. Swarming of the snails was related to the environmental changes and biology of this species. Tendency to form bigger snail conglomerations in the mouth sections of the rivers results from continuous inflow of organic matter being food supply for these organisms.
6

Seasonal and year-to-year variation of numbers of Chironomus plumosus L. and Tubificidae in a lowland reservoir: regularities, causes, mechanisms

84%
Kajak Z., Prus P.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 3
During 9 years of studies very regular Chironomus population dynamics was stated in a eutrophic, lowland dam reservoir. There were usually two peaks of the abundance: the higher one at spring (up to 80 thousands ind. m⁻²) and the much lower in autumn. The duration of the spring Chironomus generation was about 3 weeks. The constant presence of young larvae during the summer did not result in the high total abundance of larvae, mainly due to the strong predation of fish and swallows on various stages of Chironomus. The smaller predators pressure in the spring (due to fish breeding) and in the autumn (due to lower temperatures) resulted in the mentioned two peaks. The spring peak abundance was positively correlated with the chlorophyll concentration in water (feeding resource for larvae) and negatively with the water flow. There was also negative correlation of the water flow and the chlorophyll concentration, as well as abundance of Chironomus and Tubificidae during the vegetation season (April-October). Tubificidae correlated strongly positively with the spring Chironomus numbers (with a month lag). The slight positive correlation of these benthic components abundance occurred for the whole vegetation season. Tubificidae occurred in generally high numbers up to 400 thousands m⁻², but various in different years, and with no regular changes during the season.
7

Genetic diversity of perch populations in three lowland reservoirs (Central Poland): perspectives for fish sustainable management

67%
Mankiewicz-Boczek J., Imsiridou A., Kaczkowski Z., Tsiora A., Karaiskou N., Lapinska M., Minos G., Zalewski M.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 2
Proper multidimensional management of perch, common and one of the most abundant species in European freshwaters, is a challenge both from ecological and commercial perspective. However, all activity relating to the management of the perch must be based on good genetic knowledge in order to ensure a purity of species and further conservation of biodiversity. Therefore, in the present study, the mtDNA cytb and D–loop restriction analysis was applied in order to estimate genetic diversity within and among three perch (Perca fluviatilis L.) populations in reservoirs of Central Poland: Sulejów, Próba and Jeziorsko. Two out of nine, and two out of eight restriction enzymes were polymorphic for cytb and D–loop, respectively. Five different haplotypes were detected with the simultaneous occurrence of haplotype 1 in all three populations. Nucleotide diversity values within investigated populations were low (0.003 to 0.02). No significant differentiation (P = 0.248) among populations representing two different catchments of Pilica and Vistula rivers, was observed. The lack of genetic differentiation of perch populations is the first important element for the development of a strategy to regulate the perch in Polish river systems, with simultaneous reduction of fish in eutrophic reservoirs and increase in amount of perch, in sites favorable for fishing and aquaculture.
8

The dependencies between the abundance of Chironomus f. l. plumosus and bream [Abramis brama] net catches in a lowland reservoir [Zegrzynski Reservoir, Central Poland]

67%
Prus P.
Oceanological and Hydrobiological Studies
|
2009
|
tom 38
|
nr 3
15-30
9

Long-term chenges in mollusc communities in shallow biotopes of a lowland reservoir [Zegrzynski Reservoir, Central Poland]

67%
Jurkiewicz-Karnkowska E.
Polish Journal of Ecology
|
1998
|
tom 46
|
nr 1
10

The influence of littoral zone type and presence of YOY pike [Esox lucius L.] on growth and behaviour of YOY pikeperch, Stizostedion lucioperca [L.] - consequences for water quality in lowland reservoirs

67%
Lapinska M., Frankiewicz P., Dabrowski K., Zalewski M.
International Journal of Ecohydrology and Hydrobiology
|
2001
|
tom 01
|
nr 3
The influence of littoral type at presence and absence of young of the year (YOY) pike (Esox lucius L.) on growth and diurnal behaviour of YOY pikeperch Stizostedion lucioperca (L.) was investigated in triplicate (7.5 m2) field enclosures. Three types of littoral zone were applied: with homogeneous macrophytes (HOM), with heterogeneous macrophytes (HEM) and with woody debris (WD), together with control enclosure–without any structure (C). The type of littoral zone influenced the growth rate and behaviour of YOY pikeperch. The growth rates of small (<60mm) pikeperch were significantly higher in HOM than in controls, HEM and WD types of littoral. Similar but weaker relationships were found for larger pikeperch (>60mm) with their growth rates higher in HOM than in HEM and WD littoral types. At the presence of pike, the highest pikeperch growth rate was still noted in HOM, compared to WD enclosures. The results of pikeperch diurnal behaviour showed high littoral use at absence of pike (on average: 38% for C, 62% for HOM, 55% for WD, and 30% for HEM enclosures). Pikeperch utilised littoral habitat much less at presence of pike (15% for C, 8% for HOM, 3% for WD, 6% for HEM enclosures). On the basis of experiments it can be concluded that pikeperch growth rate and behaviour may be strongly affected by diversified littoral zones and by the presence of pike competition. Observed relationships may be applied for water quality control in reservoir. As a strong pikeperch population, achieved by enhancement of its growth through creation of most preferred nursery habitat (HEM), may enable to reduce zooplanktivorous fish community even in the presence of pike competition.
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