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Species and genera of soil nematodes inhabiting tree plantations on colliery spoils near Sokolov
Háněl, Ladislav
Soil nematodes were studied in 20-30-year-old tree plantations and spontaneous successions on colliery spoils near Sokolov in west Bohemia, Czech Republic. Six types of tree plantations (oak, alder, linden, larch, pine, and spruce) and one type of spontaneous succession (willow-aspen-birch), each in four replicate sites, were surveyed in March 2005 and in April 2006. In total 174 species and 86 genera were distinguished, more species and genera were found in deciduous than in coniferous plantations. Cluster analyses showed different composition of nematode faunas in those plantations. Co-occurrence of closely related .i.Aporcelaimellus, Helicotylenchus./i. species could suggest their still existing niche overlap in a developing environment whereas niche partitioning probably established between species of the genera .i.Eudorylaimus./i. and .i.Paratylenchus./i..
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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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Společenstva půdních hlístic (Nematoda) ve vybraných mokřadních habitatech Národního parku Biebrza
Háněl, Ladislav
Nine marshland habitats of the Biebrza National Park in north-east Poland were investigated for nematodes in a single survey. In total, about 170 species and 89 genera of nematodes were determined. The abundance of nematodes in individual habitats ranged from 75 to 470 x 10.sup.4./sup. ind.m.sup.-2./sup.. The order Tylenchida represented 33 % of all nematode individuals, Dorylaimida 23 % and Araeolaimida 18 %. The respective numbers of genera in these orders were 22, 22 and 9, of species 43, 43 and 24.
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Hlístice (Nematoda) v jílech hald uhelných dolů a v pokusně introdukovaných pásech luční půdy
Háněl, Ladislav
Soil nematodes were studied in coal-mining clay spoil denuded by a landslide of the upper part of a colliery dump three years ago. This control plot was compared with nematodes in introduced strips of fresh meadow soil heaped up on the spoil and in spoil strips between these soil strips. .i.Ecumenicus monohystera./i. (25% of all nematode individuals) and .i.Aporcelaimellus obtusicaudatus./i. (23%) dominated in the control spoil whereas in spoil between soil strips their population densities decreased. The greatest number of nematode species and genera was present in the soil strips. The number of species and genera increased in spoil strips adjacent to soil strips and proportions between trophic groups partially changed. Introduction of fresh meadow soil into colliery spoils may influence nematode assemblages in post-mining clays. Nevertheless, clay patches can harbour peculiar nematode assemblages that can contribute to the overall diversity of a post-mining landscape.
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Fauna of soil nematodes and other soil micro-mesofauna in spruce clearings in the Šumava Mts., Czech Republic
Háněl, Ladislav
Soil micro- and mesofauna was studied in four spruce clearings in the Šumava Mts., covered by vegetation of Junco effusi-Calamagrostietum villosae. The total average abundance of nematodes varied from 1527 to 3864 x 10 3 ind.m-2 in individual localities (mean value 2833 x 10 3 ind.m-2). Root-fungal feeders were the most abundant nematodes mainly represented by Aglenchus agricola (about 50% of all nematodes) and by Filenchus spp. (5%, mostly F. misellus). The second most abundant trophic group were bacterivores (29%,mostly Acrobeloides nanus and Plectus spp.) followed by omnivores (6%, mostly Eudorylaimus spp.). The number of nematode species in individual localities varied from 51 to 57, the number of genera from 29 to 33. Generic heterogeneity of spruce clearing fauna was relatively low (mean H´gen = 1,92), as well as the value of maturity indices (SMI = 2,19, MI = 2,40, PPI = 2,01. (The mean abundance of enchytraeids in the set of localities studied was 55 x 10 3 ind.m-2, of rotifers 134 x 10 3 ind.m-2, of tardigrades 125 x 10 3 ind.m-2, and of copepods 5 x 10 3 ind.m-2.
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Short-term effects of grass mixtures on nematodes inhabiting agricultural soil in the Bílé Karpaty Mts., Czech Republic - a preliminary study
Háněl, Ladislav
Short-term changes of nematode assemblages were studied in field soil sown with regional and commercial grass mixtures and compared with those in a cultivated field in the course of one year. Total average abundance of nematodes in the grass mixture plots increased rapidly to 1308-2075 x 10 3 ind.m.-2 whereas in the field it remained relatively low (625 x 10 3 ind.m-2). The increase in population densities mainly concerned microbivores such as Panagrolaimus, Paraphelenchus, Aphelenchus and Aphelenchoides (950-1779 x 10 3 ind. m-2) followed by omnivores + predators (178-296 x 10 3 ind.m-2), while increase in plant parasite populations was slower (105-140 x 10 3 ind. m-2). The development of nematode assemblages suggests a great role of accumulation of above-ground as well as below-ground litter supporting microflora and microbial feeding fauna in initial stages of meadow restoration. In older stages, an increase of root density is expected simultaneously with multiplication of plant parasitic nematodes. Early successional development of soil nematode assemblages seemed to be faster in plots sown with regional grass mixture than in that sown with commercial grass mixture.
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Comparison of soil nematode communities in spruce forests of the Žofín woodland area (Novohradské hory Mts.) and the upper Vydra river basin (Šumava Mts.), Czech Republic
Háněl, Ladislav
Soil nematodes were studied in two spruce forests at the Žofín National Nature Reserve and in three spruce forests of the upper Vydra river basin, National Park Šumava, in South Bohemia. The total mean abundance of nematodes in the spruce forests ranged from 863 to 4877x10 3 ind.m-2 with variation from 231 to 6947x10 3 ind.m-2 on individual sampling dates. The most abundant nematode genera were root-fungal feeding Filenchus (48,3% of all nematode individuals in the spruce forests studied), bacterivorous Plectus (11,2%), and omnivorous Eudorylaimus (8,5%). The lowest abundance but the greatest variety of nematodes was found in a waterlogged spruce forests at the Žofín Reserve whereas the greatest abundance of nematodes occurred in the spruce forests of the Vydra river basin. The nematode fauna in the two regions compared showed particular differences, especially in the groups of bacterivorous, plant parasitic and predatory species.
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