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The mode of spatial distribution of soil animals and their trophic activity was studied in the sod-podzolic soil under a spruce forest. At the test point level, no apparent relationship between the distribution of soil animals and physicochemical characteristics of the soil was observed. The patterns of distribution of detritophages and the trophic activity (measured using the bait-lamina test) were similar. The perforation of laminae in the bait-lamina test resulted from the trophic activity of both micro- and mesofauna.  相似文献   
2.
Effects of metal contamination on soil biota activity were investigated at 43 sites in 5 different habitats (defined by substratum and vegetation type) in a post-mining area. Sites were characterised in terms of soil pH and texture, nutrient status, total and exchangeable metal concentrations, as well as plant species richness and cover, abundances of enchytraeids, nematodes and tardigrades, and microbial respiration and biomass. The concentrations of total trace metals were highest in soils developed on mining waste (metal-rich dolomite), but these habitats were more attractive than sandy sites for plants and soil biota because of their higher content of organic matter, clay and nutrients. Soil mesofauna and microbes were strongly dependent on natural habitat properties. Pollution (exchangeable Zn and Cd) negatively affected only enchytraeid density; due to a positive relationship between enchytraeids and microbes it indirectly reduced microbial activity.  相似文献   
3.
This paper investigates the effects of mowing and sod removal on vegetation, soil mesofauna and soil profile, and the restoration of these features in the years following sod removal. The sampling site is located in a primary wet dune slack in the northern part of the province of North-Holland. The original vegetation is a heathland withEmpetrum nigrum andCalluna vulgaris, underlain by a Gleyic Arenosol with an O, Ah and (B) horizon development. Above-ground, the vegetation in the dune slack has been mown since 1940. The sod was removed from restricted areas in the slack at various times in the past (1980, 1985, 1987 and 1991). All three sources of data point to adaptation to wet conditions after mowing and sod removal. The vegetation of the mown area is related to the vegetation in the original heathland, although some species appear to have disappeared. Below-ground, mowing drastically reduces the number and depth of occurrence of microarthropoda. Restriction of depth applies also to the Enchytraeidae. Soil profile development is restricted to an Ah-AC-Cr sequence. Species diversity both above and below-ground is relatively high in plots where the sod has recently been cut, due to the rapid colonization by the first pioneer species. A time series for the vegetation is difficult to establish because hydrological conditions interfere with years since sod removal. Soil profile evolution after sod cutting is poor but consistent, from an AC-Cr sequence since 1991, to an O-Ah-Cr sequence since 1980. The management practices were set up with the intention to interrupt the succession to give pioneer species a chance. Neither the vegetation, nor the soil fauna or soil profile have fully recovered during the 13 yr since the first sod removal. So the goal has been reached.  相似文献   
4.
Studies on the population ofRana arvalis Nilss. frogs performed in the radioactively contaminated area near Lake Berdanish in 1993 revealed a number of features indicating that the contents of nutrients in the organisms of adults and juveniles is low. The analysis of simultaneously collected data on food supply to this population showed that the structure of food chains in the study area is simplified and the diversity and biomass of soil invertebrates (the main food for amphibians) are sharply reduced. These factors account for food deficiency, which manifests itself in a low level of stomach filling and individual energy reserves of the frogs and is reflected in their population characteristics.  相似文献   
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