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1.
The diversity and structure of the herbaceous layer were monitored on a transect through mixed forests in the Malinskaya Biogeocenotic Station (Moscow oblast, Russia). The data obtained in 1987 and 1997 were compared. The parameters of species rank distribution, number of species, and entropy estimate of specie diversity only slightly changed during that period. The total coverage and abundance changed substantially; statistically significant changes in the contributions of species to the community were revealed. Estimates of changes in the community status of species belonging to different ecological groups on the Ellenberg scale served as the basis to demonstrate that soils were eutrophicated and the climate became more continental during the period of the study. Transformations of the vegetation structure were found to be equilibrium; and the community, to exhibit elements of self-organization.  相似文献   

2.
A method for estimating the current state of plant communities based on the ecological amplitudes of constituent species is proposed. An original program, Fitoindikatsiya, has been developed to compute the indices of disturbance and homogeneity of plant communities from species ecological scale values. The current state of pine forests in the part of Novosibirsk oblast east of the Ob River has been analyzed; slightly, moderately, and severely disturbed zones have been distinguished.  相似文献   

3.
Parameters of species and typological diversity of forest vegetation have been evaluated on macroslopes descending to Lake Imandra in the vicinity of the Severonickel Mining and Smelting Complex (SMSC) (Murmansk oblast). It has been shown that these parameters change upon an increase in the pollution level, with the pattern of changes in northern taiga forests differing from that in krummholz stands. The species richness and typological diversity of forest communities increase in the middle zone of the pollution gradient, compared to those in the krummholz belt occupying the upper parts of the slopes. Species saturation in all types of communities on landscape transects consistently decreases along the pollution gradient. In general, changes in parameters of diversity provide evidence for strong digression of plant communities in the vicinity of the SMSC.  相似文献   

4.
The results of three-year studies on Collembola communities in spruce-fir forests along the gradient of pollution with emissions from the Middle Ural Copper Smelter (Revda, Sverdlovsk oblast) are presented. They show that the species and ecological structure of these communities change abruptly in the impact zone (1 km from the source of emissions), compared to the background zone (30 km from the source), which involves a decrease in the abundance and diversity of Collembola. Their total abundance and species richness in the zone of intermediate disturbance (7 and 4 km) are considerably higher than in the background zone, and the species structure of communities is characterized by superdominance. Four species groups differing in sensitivity to pollution are distinguished. Preference for zones with different pollution levels in closely related species is regarded as a case of ecological vicariation.  相似文献   

5.
The states of the populations of five dominant species of predatory mammals living in the area affected by the Kalinin Nuclear Power Plant (NPP) and in remote districts of Tver’ oblast have been compared. A total of 1120 skulls, including 708 skulls from the vicinity of the NPP, have been examined. The data on parameters characterizing similarities between the samples, the degree and structure of intrapopulation diversity, and ontogenetic stability suggest with a high probability that the Kalinin NPP has no effect on wild populations of predatory mammals.  相似文献   

6.
Coordinated soil–geobotanical studies revealed a close correlation between the species diversity of phytocenoses and soil properties in the Russkii Sever National Nature Park (Vologda oblast). Soil acidity, together with the concentrations of exchangeable calcium, potassium, and magnesium, is a factor determining variations of species diversity indices for vascular plants and bryophytes in forest biogeocenoses.  相似文献   

7.
Radioactive contamination affects soil organisms and causes profound structural rearrangements in soil zoocenoses, which are manifested in the decreased species diversity of invertebrate communities and low relative abundance of large soil invertebrates. However, these communities gradually recover their initial structure. The soil biota near the epicenter of an underground nuclear explosion performed 30 years ago in Perm oblast has been studied to reveal specific structural features of the soil macro- and microfauna. Its structural diversity is considered with regard to such components as species (taxonomic) composition, the structure of dominance, and the ratio of ecological and trophic groups.__________Translated from Ekologiya, No. 3, 2005, pp. 171–179.Original Russian Text Copyright © 2005 by Kolesnikova, Taskaeva, Krivolutskii, Taskaev.  相似文献   

8.
The state of tree and ground vegetation layers in spruce-fir forests around the Middle Ural Copper Smelter (Revda, Sverdlovsk oblast) has been repeatedly evaluated in 25 permanent sampling plots at 5- to 10-year intervals (1989–2013). The results have been used to characterize the dynamics of plant communities in the period of reduction of emissions from the smelter. Although the annual amount of emissions has decreased from 150–225 × 103 t in the 1980s to less than 5 × 103 t after 2010, the vegetation in the impact zone (1 and 2 km from the smelter) remains severely suppressed: the trees continue to die off, and the diversity of ground vegetation layer is very low. In zones with low and moderate levels of industrial pollution (30 and 4–7 km from the smelter), natural factors associated with windfall disturbance after the 1995 windstorm with snow have played a more important role in the dynamics of forest communities than the reduction of emissions itself.  相似文献   

9.
Specific ecological features of ground beetles inhabiting city parks and suburban areas were studied in the large industrial city of Nizhnii Tagil (Sverdlovsk oblast). Carabid cenoses of city parks retained considerable species diversity but proved to be strongly dominated by a limited number of species. An analysis of their state before and after recreational impact revealed changes in the species composition of communities, the set of dominant species, the degrees of their dominance, and the ratio between classes of life forms. The results show that the stronger the recreational impact, the more significant the decrease in the species diversity of the carabid community.  相似文献   

10.
The results of studies on southern taiga forests in northern Kostroma oblast are presented. They include the typing of old-growth forests, their phytocenotic and ecological characterization, and assessment of their structural and species diversity, successional status, and degree of anthropogenic disturbance. Geomorphological features of the study area and parameters of soils under plant communities of different forest type groups are described. On the basis of generalization of available data, conclusions were drawn concerning specific features of the structure and species diversity of forest communities in different ecotopes and at different stages of succession.  相似文献   

11.
Ecological and phytocenotic features of forest communities were studied in the southwest of Moscow oblast. Based on the ecomorphological groups of species prevalent in the herb–dwarf shrub and moss layers, five groups of communities typical of the conifer–broadleaf forest zone were distinguished (small-herb, small herb-large herb, large-herb, moist-herb, and mixed-herb communities), and their composition was analyzed. Discriminant analysis of the species composition of lower vegetation layers revealed significant differences between the syntaxa, with the percentage of correct classification being 89.8%. To evaluate ecological determination of the above groups of communities, a hypothesis was tested concerning the correlation of their composition with ecotope properties. This hypothesis was verified by means of (1) ordination by ecological indicator values and interpretation of the axes, (2) revealing differences in ecological regimes between habitats of the syntaxa, and (3) combined analysis of on-ground and remote sensing data, particularly spectral brightness of satellite images and morphometric characteristics of the terrain surface. The results confirmed the informativeness of the syntaxa distinguished based on the species composition of the ground vegetation layer and mapping of the ecological regimes of habitats.  相似文献   

12.
The species composition, some zoogeographical parameters, the seasonal dynamics of species diversity, and alternation of active dominant species of bloodsucking mosquitoes have been compared in two green zones of Yekaterinburg, Russia, differing in size and origin: the Southwestern Park Forest and the 50th Anniversary of Komsomol Park. Changes in the abundance and occurrence frequency of mosquitoes during two consecutive years have been studied in the park forest. Phenological parameters of mosquitoes in the natural and artificial green zones of the megalopolis are considered in connection with other parameters of biology and distribution of species.  相似文献   

13.
The current state and phytodiversity of mountain steppes in Sverdlovsk oblast have been evaluated, involving an inventory of several botanical and botanical-geomorphological natural landmarks in the steppe landscape. New growth localities of rare plant species have been discovered. Scientific and natureconservation significance of the surveyed mountain steppe areas has been demonstrated. A set of informative indices has been used to identify the key protection sites of steppe vegetation. Four sites are recommended for inclusion in the system of specially protected areas with the status of natural landmarks.  相似文献   

14.
The dispersal, population dynamics, and ecological features of the European roe deer at the northern limit of species distribution and also their visits, wintering, and breeding outside the range boundary are discussed. A significant increase in the abundance of roe deer in the northern part of the range and their largescale expansion beyond the historical distribution limit have taken place during the past decade. However, their spread in Karelia and Arkhangelsk oblast is strictly limited, depending primarily on snow depth and duration. Hunting the roe deer as a game species in the region is possible only in the south of Pskov oblast, where habitat conditions are most favorable for it.  相似文献   

15.
Small mammal communities inhabiting natural and anthropogenically transformed areas of the right-bank region of Saratov oblast are fairly similar in species composition. They are represented by wide-spread, common species that, against the background of a low population density of typical steppe species, make a major contribution to the community. The highest ecological tolerance is characteristic of the striped field mouse Apodemus agrarius, which is widespread in the study region and dominates in the majority of natural biotopes and in agrocenoses; the common vole Microtus arvalis is scarce in agrocenoses.  相似文献   

16.
An analysis is made of the effect of large spruce and birch trees on the spatial pattern of the fields of heavy metal concentrations (Cu, Pb, Cd, Zn) and pH in the forest litter formed in tree stands exposed to long-term pollution with emissions from the copper smelter in Revda, Sverdlovsk oblast. The fields formed by trees growing in the background area have a regular spatial structure: the concentrations of elements decrease with increase in the distance from the tree trunk to the edge of canopy gap, with the position of sampling point relative to the trunk accounting for more than half of total variance. In polluted areas, the regular component of the field structure is very weakly expressed, and the main role is played by higher-order heterogeneity related to the mosaic pollution pattern on the scale of tens to hundreds of meters.  相似文献   

17.
The dynamics of annual increments in the glittering wood-moss Hylocomium splendens (Hedw.) Schimp. in B.S.G. has been studied in different forest types (Kezhemskii district, Krasnoyarsk krai). The linear increment and phytomass of mosses have been measured over 7 years. The density of moss mats has been determined, and parameters of annual aboveground production under different growing conditions have been compared.  相似文献   

18.
Nine lakes in the Arkhangelsk oblast were analyzed with respect to their morphometry, hydrology, and hydrochemistry, and their zooplankton was studied for three years. The data on zooplankton abundance, biomass, the ratio of filter-feeders and predators, the Shannon index of species diversity, and average individual weight of zooplankters were obtained. Differences in the structure of zooplanktonic cenoses were revealed in lakes differing in morphometric parameters, prevailing ions (HCO3 , SO4 2–), and their concentration.  相似文献   

19.
Heavy metal accumulation by plant communities has been studied in different zones of impact of gas field development. The contents of heavy metals in different blocks of plant communities has proved to depend not only on the location of phytocenosis but also on its species composition. Communities dominated by species of the family Poaceae contain smaller amounts of heavy metals than those dominated by species of the family Asteraceae, especially of the genus Artemisia. The order of precedence in the accumulation of heavy metals in different blocks of plant communities has been revealed.  相似文献   

20.
The spatial structure of 10 populations of rare orchid species (Dactylorhiza incarnata, D. traunsteineri, Listera ovata) has been studied in rich fens sporadically occurring in Murmansk oblast. Two levels of plant aggregation within populations have been distinguished: (1) clusters of individuals and (2) isolated population subsets consisting of clusters. General spatial demographic features of orchid populations in the fens are small area (77 m2) and low ecological density (0.009 ind./m2). Characteristics of the population subsets (their number, area, composition, and distance to the neighboring subset) are species-specific and reflect the degree of species rarity in plant communities.  相似文献   

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