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The aim of the study was to compare the feeding activity of soil fauna in seven temperate forests with the application of the bait-lamina method. Seven types of temperate forests located throughout Poland (East-Central Europe) were tested, ranging from dry pine forest with a typical poor quality soil to eutrophic riparian fresh deciduous forest. Each forest type was represented by five stands and all stands altogether represented natural gradient of soil fertility, texture and vegetation diversity. Despite clear diversification between the studied forest types according to a range of soil physicochemical properties and vegetation characteristics in addition to applying recommended measurement conditions for the method, we determined that the feeding activity of soil fauna did not differ between forest types. The activity of soil fauna did not depend on site botanical characteristics or any soil physical or chemical features, indicating that the bait lamina method was useless in measuring the feeding activity of soil fauna in temperate forest soils. Differences in the feeding activity of soil fauna might result from other environmental factors that influence soil fauna feeding activity in forest stands that were not measured here, i.e., soil temperature and humidity. The differences could also be attributable to the attractiveness of the bait substrate to soil fauna, which may be different in various soil conditions.
The frequently changed temperature could have great effects on soil fauna community during soil thawing period in cold areas. Therefore, soil faunas were investigated in both the soil organic layer (OL) and mineral soil layer (ML) in the primary fir (Abies faxoniana) forest (PF), fir and birch (Betula albosinensis) mixed forest (MF) and secondary fir forest (SF) in the eastern Qinghai–Tibet Plateau every ten days between March 5 and April 25, 2009. Soil macrofauna was picked up by hand in the fields. Mesofauna was collected and separated from the soil samples by Baermann and Tullgren methods, respectively. The dominated species of macrofauna belongedto Coleoptera and Diptera at the early stage of soil thawing, and to Coleoptera, Diptera, Araneae and Hymenoptera at the later stage. However, the dominated species of mesofauna belonged to Nematode, Collembola, and Acari in the whole soil thawing. The density, number of taxa, and diversity index of soil fauna showed significant change with temperature fluctuations and reached an obvious peak when soil temperatures rising above 0°C. The density and number of taxa of macrofauna in both the OL and ML were the lowest on March 5 in the three forests, but the density of mesofauna in both the OL and ML was the highest on March 25, except for the ML in the PF. These results implied that soil fauna community was sensitive to temperature fluctuations, which is important in understanding the ecological processes in the winter–spring transitional period.
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⁻.
A new species of mites of the family Veigaiidae (Acari, Gamasida) from the USA (Oregon, Mary's Peak) is described and figured.
The fauna of zerconid mites (Acari: Mesostigmata: Zerconidae) of the Nearctic region is comprehensively revised. All known 69 species grouped in 26 genera occurring in the Nearctic region are examined. Five new genera are proposed: Betaechinozercon gen. nov., Neoechinozercon gen. nov., Paramixozercon gen. nov., Rafaskas gen. nov., and Whartonas gen. nov. Twelve new species are described: Amerozercon briareus sp. nov., Bakeras evansi sp. nov., Microzercon yamoriae sp. nov., Paramixozercon alaskanus sp. nov., P. aoki sp. nov., Rafaskas blaszaki sp. nov., Zercon lucidus sp. nov., Z. manitous sp. nov., Z. morazae sp. nov., Z. raveni sp. nov., Z. oregonus sp. nov., and Z. skorackii sp. nov. The following new combinations are proposed: Blaszakiella mahunkai (Ujvári, 2013) comb. nov., B. pardus (Ujvári, 2013) comb, nov., Paramixozercon jasoniana (Díaz-Aguilar et Ujvári, 2010) comb, nov., P. albertanensis (Díaz-Aguilar et Ujvári, 2010) comb, nov., P. borealis (Díaz-Aguilar et Ujvári, 2010) comb, nov., Betaechinozercon americanus (Błaszak, 1982) comb, nov., Neoblaszakiella alaskaensis (Ujvári, 2013) comb, nov., N. luiseae (Ujvári, 2013) comb, nov., N. nudus (Ujvári, 2013) comb, nov., and Whartonas krantzi (Blaszak, 1980) comb. nov. The genera, Mixozercon Halašková, 1963 and Echinozercon Błaszak, 1976 are excluded from the list of the Nearctic zerconid genera. Keys to the zerconid genera and all Nearctic species are provided. Main aspects of the zoogeography of the family Zerconidae are discussed.
Decomposition of litter is a crucial process in terrestrial ecosystems, determining global carbon budget and nutrient turnover. Soil faunas have been shown to accelerate the rates of litter decomposition and nutrient cycling in terrestrial ecosystems. Litter decomposition has recently been observed in winter in alpine/subalpine ecosystems, but the contribution of soil fauna to the decomposition process is not clear. Field experiment using litterbags was conducted in order to quantify the contributions of soil fauna to mass losses of fir (Abies faxoniana) and birch (Betula albosinensis) litters during a freeze-thaw season in three representative alpine/subalpine forests. The litterbags of mesh sizes 0.02 mm, 0.125 mm, 1.0 mm and 3.0 mm were placed on the forest floor in October 2010, and collected after each of the three stages of the freeze-thaw season: OF, the onset of freezing stage (26 October to December 31); DF, the deeply frozen stage (1 January to 4 March 2011); and TS, the thawing stage (5 March to 30 April 2011) over the entire 2010/2011 winter. Over the whole freeze-thaw period, the mass losses of fir litter were 11–12% (0.02 mm), 12–13% (0.125 mm), 14–15% (1.0 mm) and 17–19% (3.0 mm), and that of birch litter were 10–13% (0.02 mm), 12–15% (0.125 mm), 13–18% (1.0 mm) and 17–22% (3.0 mm), respectively, depending on the altitude. The mass losses caused by microfauna, mesofauna and macrofauna for the fir litter accounted for 6–9, 12–13 and 22–25%, respectively and that for the birch litter accounted for 8–11, 13–15 and 25–27%, respectively. Furthermore, the contributions of soil fauna to mass loss showed an increasing trend with increasing body size regardless of species at three stages of the freeze-thaw period. These results suggest that soil fauna contributes strongly to litter decomposition during the freeze-thaw period in alpine/subalpine regions.
The aim of this work was to test the suitability of microbiological methods for the ecotoxicological evaluation on the example of soils of two sites (I and II) (more and less contaminated and situated in Saxony-Anhalt, Germany). Contents of Zn, Pb, Cd, Ni, Cr, and Cu in soil ranged 787–210, 210–110, 8–1, 49–12, 130–17, and 161–70 mg kg⁻¹, respectively being significantly higher in site I. The sites differ also in respect to pH (5.2–7.5), Corg (5.66–8.27%) and type of soil. The parameters tested were following: substrate-induced respiration (SIR), activity of luminous bacteria, substrate utilization patterns on BIOLOG ECO-and GN-plates, and phospholipid fatty acid (PLFA) profiles. The respiratory coefficient QR, peak respiratory maximum and BIOLOG ECO-plates were suitable for an ecotoxicological assessment of contaminated soils. QR values (> 0.3) and peak maximum values (> 40 h) indicated stress of soil microorganisms at the most heavy metal contaminated site (site I). PLFA analysis can be used to detect various environmental stresses in the soil. The trans/cis ratio of monosaturated fatty acids (> 0.1) and the fungal/bacterial biomass ratio were able to distinguish the stress conditions in soils connected with heavy metal contamination. With increasing heavy metal content in soils the PLFA pattern are changed directionally.
Neomicrozercon nearcticus gen. et sp. nov., a new genus and species of zerconid mites (Acari: Mesostigmata: Zerconidae) are described based on material of both sexes collected in the United States of America (Oregon).
Two new species of Friesea from the Western Cape province in South Africa, F. stevenchowni sp. nov. and F. capensis sp. nov., are described. Friesea capensis sp. nov. is easily distinguished by the lack of ocelli and anal spines, while F. stevenchowni sp. nov. is distinguished from other sub-Saharan species of the genus by a combination of characters including two anal spines in the position of m1, tibiotarsi with chaeta M present, 3+3 chaetae on the thoracic tergum I and 5+5 eyes. An identification key is provided for Friesea species that are found in sub-Saharan Africa.
Blaszakiella americana gen. et sp. nov., a new genus and species of zerconid mite (Acari: Mesostigmata: Zerconidae) is described and figured. This new genus differs from the closely related Microzercon Blaszak, 1976 by the presence both of small adgenital shields with openings of adgenital glands gv2. A key for females of Zerconidae genera in the Nearctic Region is provided.
The aim of our paper was to determine selected morphometric indices of the main fabric units of humus layers in soils with different vegetation cover and contaminated by heavy metals. The study sampled soil from three sites located about 4 km NW from a zinc plant. In all humus layers decomposed organic matter occurred mainly in form of fine excrements, originated from small soil arthropods, while macrofauna excrements were the absent. The dominance of soil mesofauna over macrofauna was probably attributed to elevated heavy metal concentrations. The high concentration of heavy metals affected the major soil components, but the kind of vegetation and the degree of cover of the soil surface were as important for the development of the humus layers as heavy metal contamination.
Oribatid mites are a characteristic element of soil fauna, but they are also found in decomposing wood. However, they are often absent from publications dealing with dead wood. A core question of our study was how much the mite fauna differs between dead wood and the forest floor and at different locations on dead wood. Three dead, fallen beech logs (in the third stage of decay) in the “Góra Chełm” Reserve (Jura Krakowsko-Czçstochowska, Silesian province, south Poland) were examined for log-inhabiting species of mites. Samples were collected at seven microhabitats from the logs and the ground surface adjacent to each log was also sampled. Forty-nine oribatid species (44%) were obligate members of the intra-log community. Our study revealed strong differentiation between oribatid fauna in different microhabitats of decaying logs. No statistically significant differences in oribatid communities in beech logs of the same stage of decay were observed. It may be concluded that oribatid mites are using logs as a separate habitat rather than as an extension of the forest floor.
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