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The communities of soil mesofauna were studied in the year 2004 along three transects crossed shelterbelts of different age (6, 11 and 170 years old) and adjacent wheat fields at a distance of 0.5, 15 and 50 m. Studies were carried out in the Gen. D. Chłapowski Landscape Park near Turew, Western Poland (16°45’E, 52°01’W). The age of shelterbelts vegetation affected soil mesofauna of adjacent fields in a diverse way. The mean density of mites amounts 7.4 × 10³ ind. m⁻² and 2.6 × 10³ ind. m⁻² respectively for the shelterbelts and fields. Densities of Acarina communities were affected not only by the presence of a shelterbelt (P = 0.000) but also its age (P = 0.02) and the distance from it (P = 0.000), and these effects were similar in spring and autumn (P = 0.08). The mean density of springtail noted in shelterbelts of different age was 2.0 × 10³ ind. m⁻² and in the field sites 2.2 × 10³ ind. m⁻². Although the effect of the shelterbelts’ age on the density of Collembola was not found (P = 0.3), the densities were different in shelterbelts and in adjacent fields (P = 0.006) but statistical significance was found only between spring and autumn (P = 0.000). The distance from the shelterbelt influenced (though less intensely) the density of Collembola on adjacent field (P = 0.01). Eighteen species of Collembola were found in studied shelterbelts and fields. Isotoma notabilis Schäff. usually dominated in shelterbelts. Its contribution to abundance of communities varied depending on the age of shelterbelts (in 6 years old shelterbelt it constituted as many as 71% of the whole community). In 11 years old shelterbelt Schoetella ununguiculata (Tullb.), was more common than Isotoma notabilis Schäff. and in the 170 years old shelterbelt the dominant species was Onychiurus armatus (Tullb.). Friesea mirabilis (Tullb.), Proisotoma minuta (Tullb.), Isotoma notabilis or Onychiurus armatus dominated in adjacent fields though their contribution was depended on shelterbelt’s age and on the distance from it.
The biodiversity is a core value in all ecosystems. The nitrogen (N) addition in the form of N fertilizers has effect to a wide variety of fauna living in soils. N losses from arable land should tend not only to cause water eutrophication, but also lower soil nutrient stocks and decreasing soil fertility. This study determined the effect of N soil content in conventional tillage agro-ecosystem on the soil fauna diversity in grass stripes under the sloped arable land. My objective here is to observe soil faunal taxa living in grass filter strips. The goal of this work is to describe the relationship of soil fauna to the nitrate (NO₃⁻) content runoff from fields and captured in grass filter strips. The field work was carried out during period from May until June 2013, for soil fauna investigation the extraction in Berlese — Tullgren funnels were used. Nitratenitrogen (NO₃⁻N) was extracted from air-dried sieved soil using a 2 M KCl solution. Altogether 2,020 specimens representing 19 arthropod groups were found in twenty study sites. Most abundant taxa found practically in each of sampling site were Collembola, Acari and the suborder of Oribatid mites. Statistical evaluations revealed that the effect of NO₃⁻ concentration in the soil on the average value of the total edaphic individual numbers was statistically significant; the same applies for the abundance of Acari mites. No significant results were find for the Oribatid mites and the Collembola family; however, there was a clear trend of increasing abundance with increasing concentrations of NO₃⁻.
Life form spectrum is an informative parameter in a comparative analysis of ecological structure of Collembola communities, and a valuable indicator of conditions of soil environment. This suggests a search of adequate methods of its determination. In the present study, two methods of evaluation of life form spectra in springtail communities are compared. A usual approach is a determination of the species composition and abundance, with a subsequent formal distribution of the species present among the life form categories of a chosen system, e.g. among epedaphic, hemiedaphic and euedaphic life forms considered as dwellers of litter surface and upper horizon, of litter depth and topsoil, and of soil horizon, respectively (Hopkin 1997). By this method (A) all the specimens of a given species are attributed to the same life form. However, species populations contain juveniles with smaller body size, thinner cuticle and weaker pigmentation, which tend to be more sensitive to environmental constraints and to dwell deeper in soil than adults. Therefore the attribution of juveniles and adults of a given species to the same life form may not be accurate. Another approach is a direct attribution of a life form category to each collembolan individual during the determination process, according to the visual assessment of its morphological characters (body size and development of pigmentation, number and pigmentation of ommatidia). In that case representatives of a given species might be attributed to more than one life form category, e.g. adults to epedaphic whereas juveniles to hemiedaphic life form, or to hemi- and euedaphic life form, respectively (method B). To compare both methods, mass collembolan material of a microcosm experiment carried out in a beech-oak forest at Mikolajki Research Station (NE Poland) and aimed at investigation of mesofauna/ earthworm interactions, was used. The comparison showed a statistically significant bias between the spectra of Collembola life forms estimated by methods A and B: the latter spectrum was shifted to the favour of euedaphic forms. The range of the bias was larger in soil than in litter horizon. Method B is suggested to be closer to a real life form distribution in a collembolan community and may be used for corrections of the data obtained by the traditional taxonomic method A.
In this study the effect of different grassland managements (cattle grazing with different intensities and mowing) on soil mesofauna, i.e. mites (Acari) and springtails (Collembola), was studied. Mites and springtails are the most numerous representatives of soil mesofauna organisms living in the upper soil layers (up to 5 cm). Soil mesofauna groups or species are commonly used as bioindicators of soil health. The experiment was carried out from 2007 to 2009 in the West Sudety Mountains, Poland. Pastures and meadows were under organic farming management, without pesticides or synthetic fertilizers, and restricted livestock density. Soil samples were taken three times a year (in May−June, July and October) from pastures grazed at different frequencies: once, twice and four times a year, alternate management (grazed and mown pasture) and mown meadow. Mites were identified according to orders or suborders (Oribatida, Gamasida, Prostigmata, Astigmata), while springtails to the species level. The data were analysed using a general linear model (GLM). The mesofauna taxa in relation to the treatment and date were analysed with the canonical correspondence analysis (CCA). The data from three years showed that most soil mesofauna assemblages occurred in significantly higher numbers on the pasture grazed once or twice and on alternate managed pasture than in pasture grazed four times a year and mown meadow. The CCA analysis showed the preference of most springtail species to pasture grazed once a year, while mites preferred pasture grazed twice a year and alternate management. The number of species and the abundance of the most numerous species (Protaphorura pannonica, Desoria multisetis and Folsomides parvulus) did not differ significantly between treatments. To summarize, cattle grazing once or twice a season or alternate management (grazing and mowing once a season) have a positive impact on soil mesofauna.
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