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1.
The species composition of diatom algae in the Polistovo-Lovatskii sphagnum tract (Rdeiskoye bog, Novgorod oblast) \are studied. The systematic and ecological-geographical analyses of the flora are performed. A total of 256 species and intraspecific taxa differing in ecological specificities and frequencies of occurrence in samples are revealed. A considerable number of centric diatoms is found. It is shown that primary and secondary diatom communities are formed in large sphagnum tracts. The horizontal heterogeneity of diatom communities in sphagnum bog is revealed. The species diversities of diatom algae in different bogs are compared.  相似文献   

2.
Sphagnum acid was detected in all 30 Sphagnum species investigated. The content declines in older stem segments. Investigations have so far failed to detect this cinnamic acid derivative outside the Sphagnales. In all the Sphagnum species analysed, a second, conspicuous substance was detected, apparently identical with a degradation product of sphagnum acid produced by enzymatic reaction with peroxidase in vitro. A casual correlation between the sphagnum acid content and peroxidase activity in vivo is discussed. Glyphosate (0.5 mM) inhibits the synthesis of sphagnum acid and shikimate accumulates. Exogenously supplied phenylalanine is able to produce up to 65% reversal of the glyphosate-mediated inhibition of sphagnum acid synthesis. A mixed effect of glyphosate was found on amino acid levels. The content of sphagnum acid is also reduced by daily application of 0.1 mM l-α-aminooxy-β-phenylpropionic acid.  相似文献   

3.
Fifty nine species of testate amoebae were found in a sphagnum moss bog located in the upper Sura flow (Volga highland). The active diversity in communities of sphagnum moss biotopes was formed by 24 species. Minimal species diversity (3 species) and maximum density of organisms were noted in the driest habitat. In the habitats with the medium humidity levels, the level of species richness was similar (13–16 species) and the total density was determined by redox characteristics of the environment: under the conditions of oxygen deficit, it was two to three times lower than in an oxidized environment. The species composition specificity in sphagnum moss biotopes was determined by the degree of humidity: in the driest habitats, Arcella arenaria predominated; in the biotopes with medium humidity, Nebela tenella and Hyalosphenia elegans; and in the most humid biotopes, Hyalosphenia papilio and Heleopera sphagni. Communities of testate amoebae differed by species composition and integral characteristics at different sphagnum moss horizons: the abundance and species richness increased with depth. The proportion of living individuals in the total number of tests was 35 to 75%.  相似文献   

4.
A total of 42 species and forms have been revealed in the testate amoebae community of a transitional bog at the initial stage of transformation into a typical sphagnum bog. A distinctive features of its species composition is dominance of widespread species Assulina muscorum, Arcella arenaria, Phryganella hemisphaerica, and Euglypha laevis in the absence of common sphagnobionts of the genera Nebela, Hyalosphenia, and Heleopera. Vertical heterogeneity of the community structure is weakly manifested, since dominant species are abundant in all horizons. The highest species richness is characteristic of the marginal community formed at the boundary between a sphagnum quagmire and a reed grass-dominated fen.  相似文献   

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Dedysh SN 《Mikrobiologiia》2002,71(6):741-754
Acid sphagnum bogs cover a considerable part of the territory of Russia and are an important natural source of biogenic methane, which is formed in their anaerobic layers. A considerable portion of this methane is consumed in the aerobic part of the bog profile by acidophilic methanotrophic bacteria, which comprise the methane filter of sphagnum bogs and decrease CH4 emission to the atmosphere. For a long time, these bacteria escaped isolation, which became possible only after the elucidation of the optimal conditions of their functioning in situ: pH 4.5 to 5.5; temperature, from 15 to 20 degrees C; and low salt concentration in the solution. Reproduction of these conditions and rejection of earlier used media with a high content of biogenic elements allowed methanotrophic bacteria of two new genera and species--Methylocella palustris and Methylocapsa acidophila--to be isolated from the peat of sphagnum bogs of the northern part of European Russia and West Siberia. These bacteria are well adapted to the conditions in cold, acid, oligotrophic sphagnum bogs. They grow in a pH range of 4.2-7.5 with an optimum at 5.0-5.5, prefer moderate temperatures (15-25 degrees C) and media with a low content of mineral salts (200-500 mg/l), and are capable of active nitrogen fixation. Design of fluorescently labeled 16S rRNA-targeted oligonucleotide probes for the detection of Methylocella palustris and Methylocapsa acidophila and their application to the analysis of sphagnum peat samples showed that these bacteria represent dominant populations of methanotrophs with a density of 10(5)-10(6) cells/g peat. In addition to Methylocella and Methylocapsa populations, one more abundant population of methanotrophs was revealed (10(6) cells/g peat), which were phylogenetically close to the genus Methylocystis.  相似文献   

8.
Success in ecological restoration is rarely assessed rigorously due to insufficient planning for post-restoration monitoring programs, limited funding and, especially, lack of scientifically validated evaluation criteria and protocols. In this article, we propose the use of the Indicator Value Index technique (IndVal), which statistically determines the association of species to one or several particular site types, to obtain indicators of success at the early stages of the recovery process in restoration projects. Peat bogs extracted by the vacuum method, subsequently restored by a moss-transfer technique and regularly monitored for ~10 years were used as a model system to test this approach. We first identified 34 restored sectors of ~10 ha from 4 to 11 years old in twelve eastern-Canadian bogs. These sectors were then classified according to their degree of success in recovering a typical sphagnum moss carpet (restoration goal). Then, we retrospectively reviewed vegetation communities recorded at the third year after restoration to identify indicator species of different categories of restoration success, using the IndVal methodology. By identifying early indicator species, our method provides a tool that guides intervention soon after restoration if a site is not on a desired successional trajectory. Typical bog species, namely the bryophytes S. rubellum and Mylia anomala and the tree Picea mariana, were indicative of successful restoration; while bare peat, lichens and one species of ericaceous shrubs (Empetrum nigrum), which cope better under drier conditions, indicated sites where restoration failed. A surprising finding was that the moss Polytrichum strictum, which is known to facilitate the colonization of sphagnum in disturbed peatlands, is an early indicator of unsuccessful restoration. This finding made us question the nursing role of P. strictum at a cover threshold above ca. 30%, when P. strictum could be outcompeting sphagnum and become dominant. We conclude that the IndVal method is an effective tool to identify early indicators of restoration success when combined with a thoughtful examination of species frequency and cover within each site type.  相似文献   

9.
Results of 40-year monitoring of the agaricoid biota in four types of pine forests on Perm oblast, the southern taiga subzone, are presented. We have found that the species number of fungi in pine forests varies from 80 (sphagnum pine forest) to 194 (lichen pine forest). We have found changes in species composition and an increase in species diversity in each period of monitoring. We analyze the ecological and trophic structure and define species that are dominant in regards to the basidiome number and biomass. Despite the changes in species composition, the ecological and trophic group ratio in each forest type remains almost the same. One common feature is that mycorrhizal fungi prevail in pine forests in regards to species number (55.5–61.2% of all species in the cenosis), as well as yield (52% of all basidiomes and 94% of their total biomass). We study the relation between species diversity and productivity of microbiota with the main climatic factors. We have found that July rainfall is favorable for the fruit bearing of the agarics in a pine forest with moderate humidity in August (rs = 0.73). In swampy cenoses, June rainfall, on the contrary, has a negative impact (rs = ?0.70).  相似文献   

10.
Metal exposure might induce multiple drug resistance (MDR) in bacteria in environments devoid of antibiotics via the process of co-selection, but the extent is poorly known. Core samples from two sphagnum peat bogs in central Maine, USA, were analyzed for total Hg content and were radiocarbon dated. Culturable bacteria isolated from various core depths were assayed for antibiotic- and Hg-resistance and the presence of merA (mercuric reductase). Our results show that sphagnum peat bogs represent natural ecosystems that contain ambient levels of Hg that select for indigenous bacterial strains that are not only Hg resistant, but also possess the MDR phenotype.  相似文献   

11.
Bacteria of the genus Burkholderia are a typical component of the microbial complex of sphagnum peat bogs and constitute a substantial portion of the aerobic chemoorganotrophic isolates which are routinely obtained from these environments on acidic nutrient media. The ecophysiological characteristics of the 27 strains of such organisms, which were isolated from the peat of acidic sphagnum bogs of the boreal and tundra zones of Russia, Canada, and Estonia, were investigated in the present paper. The overwhelming majority of the Burkholderia strains isolated from these bogs were phylogenetically close to the species B. glathei, B. phenazinium, B. fungorum, and B. caryophylli, the typical inhabitants of soil and plant rhizosphere. The bog isolates utilized a broad range of substrates as carbon and energy sources, including organic acids, sugars, polyalcohols, and certain aromatic compounds. All the strains studied were capable of growth on nitrogen-free media. They developed in the pH ranges of 3.5 to 7.4 and from 3 to 37 degrees C, with the optima at pH 5-7 and 11-23 degrees C, respectively. They were therefore moderately acidophilic, psychroactive, dinitrogen-fixing microorganisms well adapted to the conditions of acidic northern sphagnum bogs.  相似文献   

12.
Biodiversity of sphagnum bogs is one of the richest and less studied, while these ecosystems are among the top ones in ecological, conservation, and economic value. Recent studies focused on the prokaryotic consortia associated with sphagnum mosses, and revealed the factors that maintain sustainability and productivity of bog ecosystems. High-throughput sequencing technologies provided insight into functional diversity of moss microbial communities (microbiomes), and helped to identify the biochemical pathways and gene families that facilitate the spectrum of adaptive strategies and largely foster the very successful colonization of the Northern hemisphere by sphagnum mosses. Rich and valuable information obtained on microbiomes of peat bogs sets off the paucity of evidence on their eukaryotic diversity. Prospects and expectations of reliable assessment of taxonomic profiles, relative abundance of taxa, and hidden biodiversity of microscopic eukaryotes in sphagnum bog ecosystems are briefly outlined in the context of today’s metagenomics.  相似文献   

13.
Increased mortality was observed in a single colony of 50 Xenopus laevis. The frogs were used as oocyte donors in developmental biology studies. Necropsy findings included dermal erythema and petechiation consistent with red leg syndrome; dermal ulcerations and white, filamentous growths on the skin were consistent with Saprolegnia sp. Microscopic evaluation of the skin and fungus revealed an astigmatid mite similar to those of the genus Rhizoglyphus. The mite was also found in the water and the biological filter of the tanks housing the frogs. This mite is considered not to be a parasite of X. laevis; instead, it feeds off moss, fungi, and detritus. Subsequent evaluation of the sphagnum moss used for shipping the frogs from the supplier revealed the same mite in the moss. Our hypothesis is that the mite was introduced into the tank with the shipment of new frogs in sphagnum moss. The mites lived within the biological filter, and were only found after the growth of Saprolegnia sp. attracted the mites to the frogs. Laboratory animal care and veterinary personnel should consider non-pathogenic species of mites in the differential diagnosis of acariasis in Xenopus frogs.  相似文献   

14.
The population of earthworms has been studied in the main types of old-growth dark coniferous forests of Pechora-Ilych Nature Reserve (Komi Republic) that have not been subject to anthropogeniс impact for a long time. Ten species of earthworms have been identified. The greatest diversity (7 species), abundance, and biomass of earthworms has been revealed in the tall-grass fir–spruce forests. P. diplotetratheca had the greatest abundance. E. nordenskioldi nordenskioldi and E. atlavinyteae had the greatest biomass. The lowest species diversity (3 species), abundance, and biomass of earthworms have been found in the largefern, blueberry–green moss, and sphagnum–horsetail fir–spruce forests. The role of deadwood in maintaining the species diversity of Lumbricidae in dark coniferous forests has been demonstrated. The complexes of Lumbricidae have been considered in anthropogenically disturbed territories, where the following species with a habitat range to the south of the northern and middle taiga have been identified: L. rubellus, A. rosea, A. caliginosa caliginosa, and E. fetida.  相似文献   

15.
The reserves of phytomass and deposited nutrition elements in a grass mire have been estimated. Two grass mires and one sphagnum bog are compared in these parameters. The sphagnum bog and one grass mire are in Poland, and the other grass mire is in Russia. As follows from the comparison, the common climatic and geochemical properties of location have effect on the chemical nature of phytomass. Grass mires have a higher content of nitrogen than sphagnum bogs. Both of the Polish bogs exhibit an increased content of K and a decreased content of Ca. The accumulation of P is characteristic of the Siberian grass mire and the accumulation of S is found in the Polish one.  相似文献   

16.
Population changes of oribatid mites were studied in a bilberry-moss spruce stand and shrub-peat moss pine stand caused by ground fire. The fire resulted in a drop of population density and changes in the species composition of mites in both forest types. In the case of the spruce stand, the restoration of species composition proceeded parallel to the formation of a bilberry-moss cover and litter and became distinct four years after the fire. In the case of pine stand, the fire enveloped only the peripheral region. After the sphagnum cover burned out, the moor dehydration began and the mineralized organogenic substrate emerged. Here, the oribatid complex was significantly rearranged and the previously dominating moisture-loving species were replaced by the mesophilous-xerophilous species typical predominantly for mineralized soils. This explains why the oribatid species composition in the burned pine stand is more similar to that in the control spruce stand than to that in the control pine stand.  相似文献   

17.
Intact sphagnum vegetation from moors in south Sweden and coastal areas of west Norway contained cultivable mycobacteria in 32% and 30% of the specimens, respectively. This frequency of specimens is lower than the 50% previously found in the partly altered moors of northwestern Germany, but the Scandinavian moors contained a larger variety of species. On both intact and altered moors M. chelonei and M. sphagni sp. nov. were found, the latter a homologous group of 151 strains. In south Sweden the highest frequency was found in S. balticum, S. recurvum. S. tenellum and S. compactum & molle. (40-65%). In coastal Norway the highest frequency was found in S. rubellum (48%) which offers favourable conditions for the accumulation of solar energy due to the red brown colour in the upper parts. Combined with a high humidity in coastal Norway in summer, this may contribute to the growth of mesophilic mycobacteria. A significant affinity of M. chelonei to S. tenellum was stated.  相似文献   

18.
When clinical isolates ofSporothrix schenckii were inoculated onto the apices of living or dead sphagnum moss plants maintained under growth chamber conditions, populations of the fungus, assessed by standard dilution plate methods, increased swiftly up to about 70-fold on moist, dead plants but did not increase on the live moss. Light and scanning electron microscopy revealed fungal growth and sporulation on and within dead plants, but no evidence of either on live plants. These data provide indirect support for the contention thatS. schenckii does not grow on living sphagnum in bogs, but rather that sporotrichosis epidemics associated with sphagnum moss are likely to result from contamination of the dead plants at some point(s) in the chain of events during or after harvest. One practical implication of our results is that precautions should be taken to insure that sphagnum moss is stored dry and that it is not wetted any sooner than necessary before use. We also report here improvement of the Mycose isolation medium by an increase in cycloheximide from 400 to 800 mg/l, chloramphenicol from 50 to 250 mg/l, and the addition of rifampicin at 20 mg/l.  相似文献   

19.
The boreal forest plays a key role in the global carbon (C) cycle, and black spruce (Picea mariana (Mill.) BSP) forests are the dominant coniferous forest type in the Canadian boreal forest. National-scale forest C models currently do not account for the contribution of moss-derived organic matter that we hypothesize to be significant in the C budget of black spruce ecosystems. One such model, the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3), is designed to meet Canada’s forest-related greenhouse gas reporting requirements. In this study our goal was to determine if black spruce forest soil C stocks are significantly underestimated by the CBM-CFS3, and if so, to determine if estimates could be improved by adding moss-derived C. We conclude that in black spruce sites, organic layer C is significantly underestimated by CBM-CFS3 compared to sites with all other leading tree species analyzed. We compiled and used published moss net primary productivity rates for upland forest systems, with decomposition rates, in mass-balance calculations to estimate mean moss-derived C in black spruce forests for feather mosses at 64 Mg C ha?1, and for sphagnum mosses at 103 Mg C ha?1. These C pools are similar to the CBM-CFS3 mean underestimation of black spruce soil organic layers (63 Mg C ha?1). We conclude that the contribution of mosses is sufficiently large that a moss C pool should be added to national-scale models including the CBM-CFS3, to reduce uncertainties in boreal forest C budget estimation. Feather and sphagnum mosses should be parameterized separately.  相似文献   

20.
For cultivation of Aedes togoi the aquatic infusion of fallen leaves, peat and dry sphagnum (0.15%S) was used and a larval diet (children's haematogen with an addition of polyvitamin "Undevit" and glutamic acid) was offered. Such cultural medium provides a rapid development of larvae and their survival, high stable weight of pupae, high fecundity and viability of imago. 7 generations were obtained without reducing the quality of culture.  相似文献   

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