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1.
We manipulated the number of saprotrophic fungi in either a complex multi-resource substratum (sterilized forest soil), or a single-resource substratum (powdered cellulose). The substrates were inoculated with five common species of soil fungi in all possible combinations (from monocultures to five species in combination). In both substrates, the rate of organic matter decomposition was positively associated with species richness. The effect of fungal diversity was much stronger in the uniform single-resource substrate ( r 2 = 0.455, P  < 0.0001) than in soil ( r 2 = 0.154, P  < 0.0001). The results document that species richness of microbial decomposers strongly affects decomposition processes, at least at the species poor end of the diversity gradient. Both, 'sampling effect' and 'species complementarity effect' contributed to the community response with the latter being much more pronounced in uniform substrate than in soil. This indicates that facilitative interactions are more important than resource partitioning for positive effects of species richness.  相似文献   
2.
Routes of aquatic allochthonous inputs (aquatic subsidies) to detrital food webs are studied, as is the effect of aquatic subsidies on the functional and taxonomic structure of soil invertebrate communities in coastal ecosystems. The study took place in the coastal zone of an oxbow lake of the Pra River in the Oka Reserve. The results indicate a strong dependence of soil animals in the coastal habitats on aquatic subsidies. Isotopic analysis shows that aquatic resources enter soil food webs not only via predators feeding on flying insects or aquatic prey, but also via saprophages decomposing organic debris of aquatic origin. The contribution of aquatic subsidies to the energy balance of soil invertebrates decreases rapidly with increasing distance from the lake. The fraction of aquatic carbon in tissues of collembolans and saprophages is negligible already a few meters from the water edge. The dependence of predatory invertebrates on aquatic resources can be traced at somewhat greater distance (tens of meters).  相似文献   
3.
Field observations on colonies of seagulls (Laridae) were carried out annually on islands of the northern Tatar Strait during 2001–2008. A general tendency towards a reduction in the number of nesting birds was observed on all islands surveyed. The anxiety factor and direct destruction of bird eggs and fledglings caused the whole or the greater part of colony to migrate to “quieter” sites on islands or the continental coast. The replacement of Larus crassirostris by L. schistisagus was observed in sites where the two species nest in neighborhood. Nesting specimens of L. schistisagus were found on islands of Lake Bolshoe Kizi, suggesting that the birds are in search of alternative nesting places that are less accessible to humans and predators.  相似文献   
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This paper presents new data on species composition, density, and migration patterns of marine colonial birds obtained during ornithological studies in Chikhacheva Bay (northern part of Tatarskii Strait) in 2001–2002.  相似文献   
6.
TPP-Sn4+ was administered intraperitoneally (25 mg/kg body weight). The study was performed for 1-30 days. A day after administration the increase in the hemoprotein level 1.4 times was observed, as well as an increase in the level of p-hydroxylation of aniline. On 7-14 days the greatest increase in cytochrome P-450 content was observed. To clarity the mechanism of TPP-Sn4+ effect on cytochrome P-450, we studied its effect on the activity of heme oxygenase and LP rate. This compound is an inhibitor of heme oxygenase activity and reduces the rate of LP in the microsomes which regulates porphyrin metabolism in the organism.  相似文献   
7.
The data on the abundance and distribution of sea birds and waterfowl at the coast of southern Primorye and distribution diagrams of the sea ducks along the surveyed coast in winter season are given. The dependence of the presence of the birds in certain coastal areas on the winter ice condition was revealed.  相似文献   
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This paper presents data on the numbers of nesting common and Kamchatka tern populations on the northeastern coast of Sakhalin Island over a more than 20-year period. Distribution maps of the main tern colonies (Chaika, Lyarvo, and Wrangel islands, and an unnamed island situated in Chaivo Bay) are given. Taking into account the current data concerning southern Sakhalin colonies, the total number of terns in Sakhalin Island is about 9000 pairs for the Kamchatka tern and up to 16000 pairs for the common tern. The main biotic and abiotic factors that determine the population dynamics and distribution of nesting terns in northern Sakhalin Island are enumerated.  相似文献   
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