Faunal diversity and dynamics of species richness and dominance of parasite communities in age series of the perch (<Emphasis Type="Italic">Perca fluviatilis</Emphasis>)

Changes in parameters of species richness and dominance in parasite communities of perch have been analyzed in the age series of hosts from two water bodies, Lake Gusinoe and Chivyrkui Bay (Lake Baikal), at the levels of a host individual (infracommunity) and a host age group (set of infracommunities). The species richness of parasite infracommunities has been found to increase in both age series due to decreasing proportions of fish affected by no more than three to four parasite species and increasing proportion of fish parasitized by more than four to five species.     

Analysis of trends in the formation of species richness of plant communities using syntaxonomy and ecological scales

On the basis of syntaxonomy of primary forests in the Southern Ural region, an analysis of trends in the formation of their species diversity has been performed in regard to heat supply, soil moisture, and general soil richness. The roles of environmental factors have been estimated using Landolt’s scales. The results have shown that communities of forest classes Querco-Fagetea, Brachypodio-Betuletea, and Vaccinio-Piceetea differ in the trends of changes in species richness along gradients of the above factors. In communities of all these classes, species richness depends primarily on heat supply, with soil richness being the second most important factor.     

Condition of the Soil Fauna near the Epicenter of an Underground Nuclear Explosion in the Northern Urals

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.     

Effect of Soybean Cultivation on Soil Collembola Community in Marshland of Sanjiang Plain,China

The Sanjiang Plain, the largest inland freshwater marshland in China, was extensive reclaimed into agricultural land. To assess the effects of marshland reclamation on Collembola, we investigated collembolan communities in a chronosequence of soybean plantations (2, 15, and 25 years) in Sanjiang marshland, Northeastern China. We found that: 1) the densities and species richness of Collembola were promoted after short-term (2 years) cultivation of soybean, but significantly decreased after medium-term cultivation (15 years); 2) the densities of epi-edaphic Collembola increased while the densities of hemi-edaphic Collembola decreased as the elongation of soybean cultivation; 3) compared with S0, two species of Collembola appeared while five species disappeared in S25. The changes of plant communities and the soil traits were supposed to be the key factors affecting the composition of soil Collembola. We thus suggest that original marshland should be saved for preserving high diversity and densities of Collembola in the Sanjiang Plain.

     

The Relationship of Dominance and Evenness with Productivity and Species Richness in Plant Communities with Different Organization Models

The relationship between dominance and evenness in plant communities organized according to different models—competitive (alpine, subalpine, and low-mountain grasslands), stress-tolerant (alpine heaths and scrubs, subalpine fens, steppes, the forest herbaceous layer), and ruderal—has been analyzed in the Western Caucasus and Ciscaucasia. No correlation between evenness (dominance) and productivity has been revealed in communities of any type. The correlation between dominance and species richness is negative and, in most cases, linear, being stronger in competitive and ruderal than in stress-tolerant cenoses. The correlation between evenness and species richness in grassland communities (the competitive model) is strong, positive, and linear, while this correlation in ruderal and stress-tolerant communities is weak or absent.     

Specific features of the oribatid fauna in high-mountain pine forests of the Eastern Caucasus in relation to altitudinal zonality

The abundance, structure, and distribution of oribatid communities in high-mountain pine forest biotopes of the Eastern Caucasus are described in dependence on elevation above sea level. The oribatid fauna of high-mountain pine forests proved to be characterized by high abundance, an assortment of dominants, and species richness. It was shown that, as the elevation increases, specific dominants typical of particular altitudinal zones appear in communities, and changes in the mass species occur. These species are stable in terms of their long-term dynamics, and zonal groups (communities) demonstrate a high species diversity.     

Abundance and diversity of aquatic macroinvertebrate communities in lakes exposed to Chernobyl-derived ionising radiation

Littoral (lake shore) macroinvertebrate communities were studied in eight natural lakes affected by fallout from the Chernobyl accident. The lakes spanned a range in ¹³⁷Cs contamination from 100 to 15500 kBq m⁻² and estimated external dose rates ranged from 0.13 to 30.7 μGy h⁻¹. General linear models were used to assess whether abundance of individuals, taxon richness, Berger-Parker dominance and Shannon-Wiener diversity varied across the lakes. Step-wise multiple regressions were used to relate variation in total abundance, taxon richness, Berger-Parker dominance, Shannon-Wiener diversity, taxon richness within major groups of macroinvertebrates and abundance of the more common individual taxa to the measured environmental characteristics (conductivity, pH, total hardness and phosphate; lake area, lake maximum depth and total external dose) of the lakes. No evidence was found in this study that the ecological status of lake communities has been influenced by radioactive contamination from the Chernobyl accident. Indeed, the most contaminated lake, Glubokoye, contained the highest richness of aquatic invertebrates. Taxon richness in the eight study lakes varied from 22 (Svyatskoe #7) to 42 (Glubokoye) which spans a range typical for uncontaminated lakes in the region. Since ⁹⁰Sr is readily-absorbed by Mollusca, estimated dose rates to this group exceeded those for other invertebrate groups in two lakes (Perstok and Glubokoye). However this study found no association between mollusc diversity or abundance of individual snail species and variation between lakes in the external radiation dose. Indeed Glubokoye, the lake most contaminated by ⁹⁰Sr, had the highest richness of freshwater snails per sample (an average of 8.9 taxa per sample).     

Factors of variation in the number of adventive species in herbaceous communities of the Western Caucasus

The saturation of herbaceous communities with adventive species in the Northern Caucasus has been estimated using as an indicator the number of such species in 0.5-m² plots. Among factors accounting for variation in the test parameter, consideration has been given to the coverage of the herbaceous layer, the species richness of communities (in 0.5-m² plots), and the numbers of adventive and indigenous species (in 15-m² plots). The field data have been processes by methods of ordinary and multivariate regression analysis. The results show that variation in saturation with adventive species between small areas of herbaceous communities largely depends on the number of such species in larger areas, their species-holding capacity, and the level of completeness of communities.     

Species richness of tree and shrub layers in riparian forests of the Western Caucasus dominated by alien species

The consequences of replacement of native dominants by alien species (Ailanthus altissima, Ficus carica, Robinia pseudoacacia, Acer negundo, and Amorpha fruticosa) in the tree and shrub layers have been studied in riparian forests of the Western Caucasus. The results show that the invasive dominant species do not always achieve higher abundance, compared with native dominants. When this is the case, however, the dominance of alien species as stronger competitors leads to reduction in the species richness of communities, because they not only intercept the greater part of resources from the environment but also provoke increasingly strict partitioning of remaining resources among associated species.     

Differences in plant species diversity between conifer (<Emphasis Type="Italic">Pinus tabulaeformis</Emphasis>) plantations and natural forests in middle of the Loess plateau

We compared differences in plant species diversity between conifer (Pinus tabulaeformis) plantations and natural secondary forests in the middle of the Loess plateau. The goal of the study was to examine the differences in the effect of stand development on species diversity and in species responses to changes between forest types and between forest layers. To clarify the effects of differences in forest management, we emphasized the functional types of plant species occurring in each forest type. The result as follow: (1) The H′ and S of tree layer were significantly lower in natural conifer forest than old conifer and secondary forest, but were not different compared with mid aged conifer forest. The H′ and S of shrub layer were significantly lower in mid aged conifer forest compared with other forest types. The H′ of herb layer showed no significant differences in the four forest types. The evenness index (J′) of tree layer of mid aged conifer forest was lower than other forest communities and its J′ of shrub layer was highest although its richness of shrub layer was lower than in the other forest types. (2) The analysis of β diversity index also indicated large differences between conifer plantations and natural forests. Although the tree layer species were similar in old plantation and natural conifer forests, they differed greatly between the natural conifer and secondary forests. The natural conifer and secondary forest species composition in shrub layer differed significantly from those in plantation and secondary plots. Tree species were significantly less common in plantations than in abandoned coppice forests. Species composition in the herb layer of different forest types was similar. (3) The management of P. tabulaeformis plantations alters plant species composition considerably; the number of sub tall-tree species is increased in old aged conifer forest, especially species dispersed by animals. Plantation management appears to affect ecological processes through seed dispersal. From the perspective of management, the change in the structure and composition of the canopy in plantations could affect the behavior of dispersers and regeneration.     

Spatiotemporal dynamics of forest-tundra communities in the polar urals

The spatiotemporal dynamics of forest-tundra communities in the 20th century have been studied in the timberline ecotone of the Polar Urals. Maps reflecting the distribution of different types of forest-tundra communities have been made, and data on the morphological and age structure of tree stands have been obtained for three time sections (the mid-1910s, 1960s, and 2000s). They show that open and closed forests have markedly expanded due to natural afforestation of the tundra and increase in the density and productivity of existing forest stands. The unidirectional pattern of plant community transition (from the tundra to closed forests) and meteorological data provide evidence that this transition has been conditioned by climate warming and increasing humidity recorded during the past 90 years.Translated from Ekologiya, No. 2, 2005, pp. 83–90.Original Russian Text Copyright © 2005 by Shiyatov, Terentev, Fomin.     

Inhibition of restorative succession by invasive plant species: Examples from southeastern Belarus

Consideration is given to the examples of suppression of restorative succession by invasive plant species (Solidago canadensis L., Helianthus subcanescens (A. Gray) E. Watson, Impatiens glandulifera Royle) in anthropogenic landscapes of southeastern Belarus. Characteristics of communities blocking the succession process have been revealed: low species richness, dominance of alien species in coverage, high level of synanthropization, and the absence of natural regeneration of trees and shrubs. It is suggested that a delay in succession is caused by the suppressing influence of transformer species on seed germination in apophytic trees.     

Structure of the communities of small mammals (micromammalia) in forests on western slopes of the Northern Urals

Long-term data on the species composition and ratio of insectivores and rodents in forest ecosystems of the western macroslope of the Northern Urals are considered. It is shown that the micromammalian communities of mountain forests are characterized by higher total abundance and polydominance and comprise greater numbers of common species than the communities of taiga forests in neighboring regions of the Russian Plain. Hence, the mountain-forest communities of small mammals have high indices of species diversity and uniformity.Translated from Ekologiya, No. 2, 2005, pp. 138–145.Original Russian Text Copyright © 2005 by Bobretsov, Lukyanova, Poroshin.     

Communities of trees along a tropical forest restoration gradient

Increasing rates of deforestation in tropical forests have been linked to agriculturalists. A critical concern generating debate is how well communities of trees recover into a more species rich ecosystem after restoration planting. The aim of the study was to evaluate the pattern of recovery of communities of tree, assess the influence of Acanthus pubescens, Lantana camara and Pennisetum purpureum, on the recovery as well as how restoration planting facilitates recruitment of other native tree seedlings along a gradient of forest restoration in Kibale National Park, Uganda after evictions of illegal settlers. We studied six restoration forests ranging in age from 3 to 16 years, naturally regenerating and three primary forests. Our results showed that recovery with natural regeneration was more effective than restoration planting although the latter enhanced recruitment of other native tree seedling. Tree recovery was generally correlated with age so that species density and diversity increased although at different rates. A reverse pattern was found for dominance but no clear pattern was found for tree density (individual/ha). Communities of tree showed directional patterns of change however community composition were still distinct among the different forests. A. pubescens, L. camara and P. purpureum negatively correlated with species density, tree density and diversity but a positive correlation was found for dominance. Restoration planting can reestablish forests with high species density, tree density and diversity, but this is dependent on age and the extent of the herbs, grasses and shrubs cover in tropical forests.     

Analysis of Catenae in the Kivach Reserve: Structure,Succession State,and Potential Composition of Forest Vegetation

Types of catenae of the moraine landscape of the Kivach Reserve have been described, and five ecotopes have been distinguished in their composition. The analysis of ecological ranges of the main forest-forming species has made it possible to predict the potential composition of a tree synusia that included five to seven species in the greater part of the catenae and three species in depressions with stagnant moistening. The population demographic approach has been used to determine the succession status of communities in the study area. Six variants of phytochores have been distinguished in the herb-dwarf shrub layer; the main ecological and succession factors of distribution have been determined for them.__________Translated from Ekologiya, No. 4, 2005, pp. 252–258.Original Russian Text Copyright © 2005 by Platonova.     

长江中游监利江段鱼类群落结构研究

基于2013~2015年、2017~2018年长江中游监利江段的鱼类资源监测数据，采用多样性指数和多元统计方法分析该江段的鱼类群落结构特征。研究表明:5年共监测到鱼类68种，隶属于6目13科，其中鲤形目共46种；2018年监测的鱼类种类数要多于其他年份。各年份的均匀度指数值相差不大，2018年Shannon Wiener指数值和Margalef丰富度指数值要大于前面4个年份，优势度指数值有一定波动，但值均偏低。ABC曲线及W统计表明2013年和2014年鱼类群落结构受到了人类活动的严重扰动，而2015、2017和2018年受到人类活动的扰动程度不大。聚类分析和非度量多维尺度分析显示鱼类群落可以分为三组，但相似性分析表示三组间无明显差异。     

The effect of natural and anthropogenic disturbance in forest canopy and its effect on species richness in forests of Uttarakhand Himalaya,India

Pinus roxburghii (chir-pine) and Quercus leucothchophora (banj-oak) are dominant forests of mountainous part of the Uttarakhand Himalaya. The continued anthropogenic disturbance is opening the canopy, forming canopy gaps and as a result forest fragments are developing. Thus, the present study aims to analyze variations in species richness and vegetational parameters in relation to canopy gaps in forests. Total species richness was greater in open canopied forest compared to moderate and close canopied forests. In comparison between oak and pine forest, it was greater in oak forest while the proportion of common species was low between oak—pine forests. Mean species richness did not significantly vary from one canopy gap to another as well as in oak and pine dominated forest. This indicated that dominant forest types played an important role to form the community structure. The shrubs richness were greater in closed canopy and between the forests it was greater in pine forest. Tree and shrub density was low in open canopy while herb density was high in moderate canopy. Thus, this study indicated that the dominant canopy species play an important role in deciding the community structures especially the distribution of under canopy species. These parameters should be considered for conservation and maintenance of plant biodiversity of a region.     

The use of ecological scales for indication of the current state of forest communities

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.     

Structure and species diversity of topical groups of mollusks in lakes of the Solovetsky Islands and Onega Peninsula, northwestern Russia

The main differences in the structure and species diversity of topical groups of mollusks between lakes on Solovetsky Island and continental lakes have been revealed. Insular groups are characterized by higher indices of species richness (the average number of species per sample) and density, with the level of dominance being decreased. In general, specific features of the insular territory impose limitations not only on the total species richness but also on the number of structural variants of topical mollusk groups, with the range of parameters of their species diversity being reduced against the background of sharp increase in the density of mollusk colonies. Insular topical groups of mollusks are characterized a certain set of species dominating in abundance.     

Spatial distribution of coarse woody debris in pine forests of the Marii El Transvolga region

The spatial distribution of coarse woody debris in pine forests has been studied in the Transvolga region of the Marii El Republic. For this purpose, 30 test plots have been established in pine (Pinus sylvestris) stands of the study region. The results are indicative of a tendency toward the spatial grouping (clustering) of woody debris by fractions, decomposition classes, and stocks along with increase in stand age.