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1

Dispersion of Didymosphaenia geminata in the flowing waters of southern Poland - new sites of species occurrence in the Orawska watershed and the Orawska basin

100%
Noga T.
Oceanological and Hydrobiological Studies
|
2003
|
issue 4
159-170
EN
To date, Didymosphaenia geminata has been recorded in boreal and montane regions in Europe, Asia and North America. It has been recorded only rarely in central Europe in cold, oligotrophic montane water bodies with a moderately low electrolyte content. In Poland, it occurred in the streams in the Tatra Mountains and in the Dunajec River but abundance was low. During the 1990s this species appeared in the Carpathian tributaries of the Vistula River (So?a, Skawa and Raba). Very high Didymosphaenia geminata abundance was noted in the San River below the dams in mezotrophic environments. Didymosphaenia geminata was recorded for the first time in mezotrophic environments in the Czarna Orawa River and its tributaries, most of which - Zubrzyca, Sylec and Lipnica - come from Babia G?ra Mountain. The highest abundance was noted in the Zubrzyca stream where there were macroscopic aggregations. The most common species in these aggregations were Navicula capitatoradiata, N. lanceolata, Cymbella minuta, Achnanthes biasolettiana var. biasolettiana, Fragilaria arcus var. arcus, F. ulna, Diatoma vulgaris and Cocconeis placentula var. euglypta
2

Diatom communities in Moss Creek (King George Island, South Shetland Islands, Antarctica) In two summer seasons: 1995/96 and 2001/02

88%
Noga T., Olech M. A.
Oceanological and Hydrobiological Studies
|
2004
|
issue 4
103-120
EN
This paper focuses on the diatom flora of Moss Creek in Antarctica that was collected during two summer (1995/96 and 2001/02) seasons. Of the 95 taxa identified in Moss Creek, two groups of diatom communities were distinguished. Achnanthes germainii, Eucocconeis ninckei, and Nitzschia homburgiensis, taxa indicative of unpolluted waters, dominated in the upper course of the creek. The other group was found in the lower reaches of the creek and included taxa indicative of eutrophic environments. In this part of the creek Mayamaea atomus associated with Nitzschia gracilis and Planothidium lanceolatum were dominant. In both sampling periods the species composition of the dominant taxa was similar with the distinct predomination of Mayamaea atomus. During the 1995/96 season, Nitzschia gracilis, N. homburgiensis, and Planothidium lanceolatum also occurred abundantly, whereas in 2001/02 the proportions of Nitzschia gracilis and Planothidium lanceolatum showed a slight increase.
3

Feeding habits, fine structure and microhabitat preference of Euthyplocia hecuba (Hagen, 1861) (Ephemeroptera: Euthyplociidae) nymphs from Honduras

75%
Fenoglio S., Bo T., Czekaj A., Rosciszewska E.
Folia Biologica
|
2008
|
vol. 56
|
issue 1-2
43-49
EN
The Euthyplociidae are a tropical and subtropical Ephemeropteran group. The aim of this study was to augment knowledge on some aspects of the biology and ecology of Euthyplocia hecuba (Hagen, 1861) nymphs. Mayflies were collected in the Rio El Padre, located on the Caribbean slope of Honduras. Diet, microhabitat preference and some fine morphological aspects of the nymphs were examined. E. hecuba nymphs are very specialised organisms that occupy a specific ecological niche in the lotic/benthic community. Immature stages show an evident preference for life in soft and fine substrata. They are detritivorous burrowers that ingest large amounts of fine particles deposited by river flow in sedimentation areas. They show peculiar morphological adaptations for life in this particular substratum, such as mouthparts modified for digging and collection of fine organic sediments, digging legs with shovel-like tibiae and massive femora, and filamentous gills.
4

Effect of different light conditions on cyanobacteria and algal communities in Tatra Mts stream (Pland)

75%
Kawecka B.
|
|
issue 2
3-14
EN
Different light conditions at the open and shaded sites caused by marginal vegetation affected the structure of Cyanobacteria and algae communities, but had no effect on chlorophyll a content. In the open area Hydrurus foetidus (Villars) Trevisan, Homoeothrix janthina (Bornet et Flahault) Starmach, and diatoms (mainly Achnanthes minutissima Kutz. together with A. biasolettiana Grun. and species from the Gomphonema genus ) were the most numerous. In shadow the abundance of Hydrurus foetidus drastically decreased, whereas the diatom biomass index, Achnanthes minutissima and A. biasolettiana showed a tendency to reduce their number. On the contrary, the abundance of green algae and Cocconeis placentula Ehr. var. euglypta Ehr. increased. Chlorophyll a contents of both sites obtaining the highest values in summer - autumn and the lowest in the winter - spring seasons.
5

Recent environmental toxic effect in the Polish Copper Mining Territory on human reproduction. Part I. Response of the placenta to the chemical stress

75%
Zadrozna M.
Folia Biologica
|
2003
|
vol. 51
|
issue 3-4
201-205
EN
collected from healthy non-smoking women living in the high polluted region, i.e. the Copper Mining Territory (CMT) and the 38 control placentas (C) obtained from little polluted eastern Carpathian regions. The placentas were studied by histochemical, immunohistochemical and morphometric methods. In CMT placentas a decrease in the cytochrome c oxidase and glucose-6-phosphate activities and the immunoreactivity of glutathione S-transferase pi in the villous syncytiotrophoblast and amniotic epithelium was noted. All CMT placentas showed abundance of mineral and fibrinoid deposits and of lipid droplets. This produced a compensatory increase in the mother-fetus exchange area due to excessive proliferation of placental villi which in turn decreased the intervillous space and thus the influx of indispensable maternal blood. Lately slight signs of increase in the cytochrome c oxidase activity accompanied by a noticeable decrease in number of the thinnest (most abundant) terminal villi is observed.
6

Response to drying of cyanobacteria and algae communities in Tatra Mts stream (Poland)

75%
Kawecka B.
Oceanological and Hydrobiological Studies
|
2003
|
issue 1
27-38
EN
The structure, dynamics and chlorophyll a content of lithoreophilous communities of Cyanobacteria and algae in two periodically drying sectors of the stream: in its upper (alpine ), and middle part (forest) zones were investigated. In both sectors the diversity of species was low. After snow melt, in the upper part, the stones were successively colonized by Cyanobacteria (with Chamaesiphon polonicus (Rostafinski.) Hansgirg prevailing), and green alga Klebsormidium rivulare (Kutz.) Starmach, finally obtaining stable and abundant communities. In the middle part of the stream, a spring explosion of Klebsormidium rivulare and species from the Chlorococcales group was observed. They developed temporary, since they disappeared after the June spate. Later this area was colonised mainly by Homoeothrix janthina (Bornet et Flahault) Starmach, Hydrurus foetidus (Villars) Trevisan, and diatoms, coming from a neighbouring non drying part of the stream. The chlorophyll a content in both sectors was low (2 - 55.8 mg m ?2) .
7

Competition between bacterial strains nodulating leguminous plants

63%
Golinska B., Madrzak C. J.
Biotechnologia
|
1999
|
issue 3
106-142
EN
Successful nodulation of legumes by rhizobia is a complex process that in open field depends on various environmental and biological factors. Generally legume productivity may be improved by inoculation with selected, highly effective in diazotrophy root nodule bacteria. However, field legume inoculation with Rhizobiaceae species is very often unsuccessful due to the presence of native strains in soil which are better adapted and usually dominate over introduced bacteria. The ability of one strain to outnumber others in nodule occupancy is commonly termed competitiveness. This feature of strain is genetically regulated by numerous bacterial genes, as well as it is highly dependent on host plant genotype and environmental cues. The competitiveness of endogenous strains is critical for the successful use of inocula to introduce the quality strains. In this paper we describe ways and means which should be considered in order to manipulate both established and introduced strains ecologically, edaphically and genetically to improve legume productivity and, as the consequence, soil fertility.
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