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Dominantní hlístice (Nematoda) v prvních patnácti letech primární sukcese na výsypkových jílech
Háněl, Ladislav
Soil nematodes were studied at 13 sites in the colliery spoil heap Pastvina formed of tertiary clays and left to spontaneous succession in the Sokolov coal mining district,Czech Republic. The one-year-old site had a very low abundance of nematodes (1,1-2,7 ind.cm.sup.-2./sup.), in the 5-year-old site nematode populations increased considerably (51,3-137,4 ind.cm.sup.-2./sup.) and in older sites they varied (7,9-1023,0 ind.cm.sup.-2./sup.) without detectable relationships with the age of the site. On the other hand, the diversity of nematode assemblages increased with the age of the site and developing plant cover. Bacterivorous and fungivorous nematodes occurred at all sites, having a eudominant position in many assemblages. The distribution of omnivores was variable as some species dominated in the 5-year-old site (.i.Eudorylaimus bombilectus./i.) whereas other (.i.Aporcelaimellus obtusicaudatus./i.) appeared and became eudominant in 14-15-year-old sites.
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Chironomid communities of the Upper Stropnice River (Novohradské Mountains, South Bohemia)
Chalupová, Š. ; Matěna, Josef
The communities of chironomid larvae of the Upper Stropnice River were studied semiquantitatively between the river kilometres 40-55 during 2000 and 2001. Altogether 29 taxa were observed. Dominant forms were .i.Apsectrotanypus trifascipennis./i., .i.Macropelopia nebulosa./i. and .i.Prodiamesa olivacea./i.. The water quality calculated according to the chironomid communities corresponds to beta-mesosaprobity, only in the area of Upper Stropnice village it deteriorates to alfa-mesosaprobity. This fact gives evidence to presence of point sources of organic pollution. Further downstreams the values of saprobity return to the state above the source of organic pollution. In the anthropically influenced area of the stream the decrease in the diversity of chironomid communities occured. It is necessary to consider the results as preliminary, because the only family Chironomidae was analysed in detail, for exact results the analysis of the whole macrobenthic community is necessary.
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