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Summary We tested the effects of two organic fertilizers (composts) and lime on the soil fauna of a spruce stand. One compost was obtained from chopped wood and the other from household garbage. At the time of distribution the pH of the control plots averaged 3.2, the garbage compost had a pH of 7.5, and the wood compost of 6.2. During the experimental period the pH of the compost layers decreased. The pH of the former litter layer beneath the composts showed a steep increase after 5 months, but beneath the treatment with wood compost this effect did no persist. Liming increased the pH only slightly in the litter layer. The two types of compost, the litter layer, and lumbricids (Lumbricus rubellus) were analyzed for concentrations of essential and potentially toxic elements. The element burden was highest in the garbage compost with 7- to 11-fold concentrations of Zn, Cd, Pb, Mg, and Cu compared to the needle litter. K, Ba, and Ca were 4 times more concentrated. L. rubellus showed an increased Cu concentration after extraction from the highly contaminated sites of garbage compost. Despite the differences in Pb contamination in the needle litter and in the two compost types, all investigated individuals of L. rubellus contained similar concentrations of Pb. In contrast to Pb, Cd accumulated in this lumbricid. Seasonal fluctuations of microarthropods, their total abundance, and differences in the colonization of the compost layers were observed. Collembola abundance was significantly increased in the garbage compost plots in July 91. There were generally more Prostigmata in the control and limed plots than in the compost plots. Oribatid numbers fell under all treatments compared to the controls. Mesostigmata were identified to species level and 33 species were found in the experimental areas. Certain species, such as Arctoseius cetratus and Uropoda minima, were only found in the treated sites. 相似文献
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Studies of biological responses in the terrestrial environment to rapid changes in climate have mostly been concerned with aboveground biota, whereas less is known of belowground organisms. The present study focuses on mites and springtails of heathland ecosystems and how the microarthropod community has responded to simulated climate change in a long-term field experiment. Increased temperature and repeated drought was applied for 13 years to field plots located in Wales, The Netherlands and Denmark representing sites of contrasting climatic conditions with respect to precipitation and temperature. This approach provided an opportunity to study biological responses on a local (within sites) and regional scale. Warming treatments increasing night time temperature (0.3–1 °C higher than ambient at 5 cm soil depth) had no detectable effects on the microarthropod communities. Increased intensity and frequency of drought had only weak persistent effects on springtail species composition, but practically no effect on major mite groups (Oribatida, Prostigmata or Mesostigmata) suggesting that ecosystem functions of microarthropods may only be transiently impacted by repeated spring or summer drought. 相似文献
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本文研究并描述了在重庆发现的三皱甲螨属一新亚种,定名为阿杜三皱甲螨缙云亚种,新亚种Rhysotria ardua jinyunia Lee et Chen ssp.nov. 相似文献
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郑波益 《中南林业科技大学学报(自然科学版)》2002,22(1):90-92
报道了赤螨科波赤螨属在中国分布并记述该属一新种,中国波赤螨新种Bochartia
chinensis sp. nov..新种与该属已知种的区别明显.新种标本用马氏网采自湖南石门壶瓶山自然保护区.模式标本保存在中南林学院昆虫标本室. 相似文献
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Georgia Erdmann Andreas Floren K.Eduard Linsenmair Stefan Scheu Mark Maraun 《Pedobiologia》2006,50(5):433-441
This study investigates the effect of forest age (20-, 50-, 160-year-old, and primeval forest) on oribatid mite communities on the bark of oak trees in the National Park Pusza Białowieża in eastern Poland. We hypothesized that oribatid mite diversity on bark peaks at forests of intermediate age and that the number of parthenogenetic species of oribatid mites is highest in young stands. In contrast to these hypotheses, the diversity, density, number of juveniles, community structure and the mode of reproduction of oribatid mite species were not significantly affected by forest age. None of the oribatid mite species occurred exclusively on trees of a specific age. The results suggest that oribatid mite communities on the bark of trees are minimally affected by tree harvesting regimes. In contrast to oribatid mites in soil, communities on bark appear to be less sensitive to disturbances. 相似文献
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跗线螨属一新种(蜱螨亚纲:跗线螨科) 总被引：3，自引：0，他引：3
张新虎 《甘肃农业大学学报》1992,27(1):69-71
本文描述跗线螨属一新种.该新种与Tarsonemus waitei(Banks,1912)很相似,但新种T.maximus依其特别大的体形(长320μm,宽172μm)和跗节Ⅱ上所生的TaBβ、后体背板上的e毛(≥10μm)和h毛(25～30μm)长于d毛(14～15μm)和/毛(18μm)、前体背板上无表皮内突以及月牙形的腹板突(Tegula)等特征易与T.waitei及本属其它已知种相区别。 相似文献
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This experiment was a part of a research on the soil community in anthropogenous birch stands in Finland. In that study it was found that communities of Collembola are similar in birch stands of different origin (cultivated field or spruce forest), while the communities of Oribatida are essentially different. When compared to original spruce forest, the communities of both groups are different.Cultivation eliminates the populations of most microarthropod species, that have to disperse after reforestation from the surrounding areas. The aim of the experiment was to study the ambulatory dispersal of soil microarthropods. It was carried out in plastic boxes filled with an intact block of defaunated surface soil taken from a birch stand that was established ca. 30 years earlier on a cultivated field. A strip of intact spruce forest soil was placed at one end of the boxes to harbour the source populations. At the opposite end we placed a row of pitfall traps. Soil samples were taken every two weeks at increasing distances from the source soil using a metal corer, and animals were extracted in a high gradient apparatus. The pitfalls were also emptied every two weeks. The experiment lasted for ten weeks.Pitfall and soil sample data gave an estimation of the maximum dispersal rate for each species or genus. The distance that the populations could potentially disperse in 30 years (age of the stand) indicated that some, but not all of the species could have actively migrated to the central parts of the birch stand (30 m). 相似文献
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