Significance of rodent population dynamics for the formation of long-term community structure

Changes occurring with time in the structure of communities are evaluated and strategies of community functioning are described using the example of murine rodents from three areas of Western Siberia that differ in landscapes and geographical conditions. Many rodent species are common to all communities included in analysis. The populations of these species have different ranks in the dominance structure of communities, depending on the natural climatic conditions of the landscape, and differently influence the composition of communities and time course of changes in their structure.     

水位变动下三峡库区消落带植物群落特征

水位变动是湿地的基本特征之一，对湿地生态系统意义重大。为了解水位变动对三峡库区消落带植物群落的影响，于2010年8月对白夹溪消落带植物群落进行调查，采用TWINSPAN分类法对植物群落进行分类。结果表明:共发现维管植物85种，隶属34科70属；植物群落可划分为18个类型，狗牙根等5种群落为白夹溪消落带代表性植物群落；随着淹水程度的加深，群落组成呈现出由旱生植物到湿生植物的过渡趋势；植物群落香农指数、均匀度指数、丰富度指数和生物量指数随水位梯度呈“∧”型变化趋势，辛普森指数呈“∨”型变化趋势。与156 m蓄水周期相比，植物物种数量、群落类型及组成、多样性均发生改变。水位变动是消落带新生湿地植物群落变化的主要驱动因子     

Models of taiga-steppe communities on the western coast of Lake Baikal

As a result of monitoring spatial changes in the cenotic structure of plant communities at the taiga-extrazonal steppe boundary on the western coast of Lake Baikal, models of taiga-steppe communities reflecting the formation, dynamics, and genesis of forests in the taiga zone have been constructed. Changes in the species composition of communities, mesophytization of steppes, the expansion of moss synusiae characteristic of polydominant dark conifer and light conifer taiga forests, active forest invasion into steppe areas, and the presence of dark conifer tree species in light conifer forests have been revealed.     

Small mammal communities in forest ecosystems affected by urbanization

A set of characters has been used to evaluate transformations in forest phytocenoses and their small mammal communities affected by urbanization, compared to conditionally undisturbed phytocenoses (communities). In park forests of the city of Yekaterinburg, the understory and subordinate shrub and herb-dwarf shrub layers of phytocenosis are transformed to a greater extent. The undergrowth of conifer forestforming species is as a rule sparse or absent, and that of deciduous trees often consists mainly of invasive species. Small mammal communities in pine forests transformed under the effect of urbanization also undergo changes leading to the formation of relatively stable (for an urbanized environment) zoocenoses differing both in species composition and in parameters characterizing community diversity.     

Composition, structure, and formation factors of bottom invertebrate communities in lakes of the southern Ob-Irtysh interfluve

The composition and structure of bottom invertebrate communities have been studied in 37 lakes of the southern Ob-Irtysh interfluve in 2008–2011. The aquatic fauna of these communities includes 146 species of eight classes. The influence of the main abiotic ecological factors (hydrophysical and hydro-chemical parameters of water, bottom substrate type) on the composition and fauna of bottom communities have been estimated. It is shown that hydrochemical factors determining the total salt content of the water, substrate type, and water transparency have the strongest effect on the level of bottom invertebrate community development.     

The status of mammal populations in the middle Urals and factors determining their distribution and density

Changes in the distribution and abundance of some game mammals have been analyzed over the past 100–150 years. Correlations between changes in the population density of species in slightly and strongly transformed habitats have been revealed, which show that the influence of anthropogenic factors on the population density of species has a highly complex pattern. Transformation of habitats leads to disturbances in the species composition of communities, changes in the population density of species, and disruption of functional relationships between them.     

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.     

汉江上游平川段鱼类群落多样性及空间格局分析

2016年5~6月对汉江上游平川段11个采样点开展鱼类多样性及水环境因子调查，共采集鱼类29种，隶属于3目5科25属，其中鲤科鱼类最多（21种，物种占比72.41%），其次为鳅科（5种，物种占比17.24%）。汉江上游平川段鱼类鱼种多样性水平分布呈现中间段低两端段高的特点，鱼类多样性垂直分布符合随海拔升高物种多样性指数下降的规律。采用非度量多维标度排序（NMDS）和典范对应分析方法（CCA）分析了鱼类群落空间分布特征及水环境因子对鱼类群落格局的影响。NMDS结果显示该河段各个站点鱼类群落分布并未出现明显的聚类特征。CCA分析结果表明水环境因子中电导率，五日生化需氧量，pH和硫酸盐浓度对平川段鱼类群落结构有极显著的影响。     

滇池人工湿地的植物群落学特征研究

用植物群落生态学方法,研究了滇池小河口的天然湿地以及表流和潜流两种人工湿地的植被群落学特征。研究区内调查发现有12种植物群落,包含有植物17种。结果表明：表流人工湿地的群落多样性大于潜流人工湿地,甚至也大于天然湿地;在两种人工湿地中,植物群落中的层次数比较接近;从植被群落结构来看,在物种多样性和shannon wiener指数方面表现为潜流人工湿地大于表流人工湿地,天然湿地居中。从天然湿地到表流湿地,再到潜流湿地,随着湿地环境水文条件的变化,植物群落组成与分布状况也在变化,表现出从湿地植物向陆生植物演替的趋势。研究表明两种人工湿地中的芦苇（Phragmites australis）群落长势不同。在人工湿地中适宜构建芦苇群落,在表面流人工湿地植物选择中可以考虑水芹菜（Oenanthe stolonifera）和慈菇（Sagittaria sagittifolia）。人工湿地的水文条件与湿地植物之间的相互关系是人工湿地进一步研究的重要方面。     

Biodiversity of forest vegetation under industrial pollution

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.     

Saturation and invasion resistance of non-interactive plant communities

Open plant assemblages in shoals of western Caucasian rivers were used as examples to analyze the relationship between the species saturation and the number and total abundance of alien species in non-interactive communities. Invasion of exotic species into highly saturated communities has been demonstrated to be, on average, less probable than their invasion into unsaturated communities. A hypothesis explaining the relationship between these parameters has been put forward. According to the hypothesis, the number of alien species in a specific locality in a community is determined by their ratio to the number of native species in the species pools of these communities; and their mean abundance, by the ratio of the total number of species to the number of individuals in the localities. Both ratios are smaller in saturated biocenoses, which determines a relatively small admixture of alien species in them.     

花桥典型地块景观格局及植被群落结构指数评价与制图研究

自然过程是规划过程的重要维度。与中国法定规划体系相衔接的生态单元分类、评价系统的构建,是生态研究与城乡规划之间的一座桥梁。选取昆山花桥为研究对象,以2010年Landsat遥感数据TM影像图为主要数据源。在城乡生态单元制图的基础上,从区域景观格局的宏观角度分析城市化、乡村以及城乡交错带三类典型地块的生态用地特征。研究表明:城市水体形态过于笔直、公园绿地分布过于集中,城乡交错带水体破碎化严重、人工景观呈集聚状的发展趋势,乡村地块水体受农业活动影响严重、农田景观应重点保护等。进而从微观角度进行植被群落结构指数评价,作为生态信息的重要补充。根据植被指数图谱可得花溪公园附近的植被群落结构指数较高,河道两侧的线性连续性整体尚佳,植被群落结构丰富,而道路两侧的植被较为单一等。旨在提供一种城市生态评价体系,从宏观到微观,从生态格局分析到植被群落结构评价,希望能更清晰的反映不同区域之间的生态价值差异,为城乡绿地系统规划提供生态基础性数据。     

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.     

Changes in the size structure of carabid communities in forest ecosystems under technogenic transformation

The body size structure of carabid communities has been analyzed based on the 2009 and 2013 collections (with the use of pitfall traps) performed at 10 sites of a spruce–fir forest along the gradient of pollution with emissions from the Middle Ural Copper Smelter. A reduction in the unweighted mean body size of carabid individuals has been shown, as well as the heterogeneity of body sizes in the community (Gini coefficient) of the extremely polluted territory. It has been revealed that the weighted mean body size of individuals and the Lorentz asymmetry coefficient are not dependent on the level of pollution. Differences between the communities of carabids in the background and polluted territories are associated with the smaller number of large-sized species, while the similarity is explained by the dominance of medium- and small-sized species at all sites. The high interannual variability has been observed in the ratio of size groups of the analyzed communities at the background and moderate levels of pollution.     

Abundance of orchids on calcareous grasslands in relation to community species,environmental, and vegetational conditions

The abundance of Orchidaceae on three calcareous grasslands is studied in relation to floristic composition, environmental and vegetational factors and plant traits (ecological and life forms). The aims are: (i) to identify a group of species that is significantly correlated with the abundance of Orchidaceae or with individual species of orchids on calcareous grasslands; (ii) to study the relationship between traits associated with habitat specialisation, community life forms and the abundance of orchids; (iii) to identify the main environmental and vegetational predictors of the abundance of orchids. A shortlist of species is found to be significantly correlated with the abundance of total orchids, Orchis pauciflora and O. morio. The life forms of the community species do not show any correlation with the orchids, with the exception of Orchis pauciflora, which tends to increase in communities rich in hemicryptophytes and poor in annual species. Analyses of Orchis morio seem to suggest that it has a high level of ecological tolerance. The most important predictors of the abundance of orchids are the substrate reaction (basic) and arid grassland with low herbaceous vegetation cover (i.e. high soil reaction and luminosity values, positive correlation with the cover of lichens and rockiness, negative correlation with tree cover and herbaceous layer). The least favourable sites were the least basic and most superficial and arid sites.     

Ecology of ground beetles in an industrial city

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.     

乌江梯级电站开发对大型底栖无脊椎动物群落结构和多样性的影响

为了解乌江贵州段的底栖动物资源现状以及梯级电站开发对底栖动物群落结构和多样性的影响，对18个断面的底栖动物进行了调查。底栖动物多样性通过Shannon Wiener多样性指数进行计算。结果显示：自然河段中，底栖动物物种丰富，以节肢动物占优势，物种丰富度和密度均以思南断面最高，生物多样性则以沿河二桥断面最高；群落类型复杂，环节动物 软体动物 节肢动物为优势群落，软体动物为群落中的优势类群。梯级水库的修建使底质环境差异变小，底栖动物物种丰度、密度和生物多样性降低，群落类型趋于简单，优势类群表现不明显，并且水库建成的年代越久,底栖动物的丰度、密度就越低,群落的组成类群就越少，物种组成以寡毛类和摇蚊类为主。研究表明,梯级电站的修建对底栖动物的物种组成、密度分布、多样性、群落类型等都造成了负面影响。〖     

Responses of small mammal community to environmental pollution by emissions from a copper smelter

Analysis of the effect of emissions from the Karabash Copper Smelter (Southern Urals) on the small mammal community has shown that its abundance and structure change significantly under technogenic impact. Structural transformations are accompanied by changes in the composition of dominant species. The “dose-effect“ pattern of community response to this impact is nonlinear: for most species of murine rodents and small insectivores, habitat quality becomes satisfactory at a distance of 9–11 km from the emission plume.     

Altitude dependent 137Cs concentrations in different plant species in alpine agricultural areas

The Gastein valley in the Central Part of the Austrian Alps was one of the regions most heavily affected by fallout of the Chernobyl nuclear catastrophe, depositing (137)Cs inventory up to 70 kBq/m(2) in May 1986. In many studies dealing with the uptake of (137)Cs by vegetation used for farming, a significant correlation between (137)Cs concentration in the plants and altitude a.s.l. has been observed. In order to quantify the influence of the composition of plant communities on the average (137)Cs concentration in vegetation on farmland, plant-specific activity concentrations in plant species have been determined. Alongside a transect from valley sites at 850 m a.s.l. to alpine pastures at 1660 m, the aggregated transfer factors C(ag) (m(2)/kg) have been measured for plant communities and plant species. C(ag) values for mixed vegetation are more or less similar in valley sites, but they increase exponentially with a doubling height of 122+/-22 m above appr. 1200 m altitude a.s.l. On average all species are affected by this increase in a similar way. C(ag) values of ubiquitous plant indicate that the composition of plant communities is of minor importance for the contamination of mixed vegetation.     

Communities of phyllophagous insects in young birch greeneries of northern cities

Phyllophagous insect assemblages on birch trees have been studied in greeneries of the cities of Labytnangi and Salekhard and natural habitats in the environs of these cities in 2007, 2010, and 2013. The 44 recorded species were dominated by insects of the orders Lepidoptera and Hymenoptera (18 and 12 species, respectively); regarding feeding ecology and mode of life, they were dominated by open-living chewing phyllophages and miners (19 and 10 species). The urban greeneries and sparse birch forests were colonized by the same species, but the density of many species in the cities was considerably higher. The species composition of the communities changed considerably from year to year. The species richness and similarity of insect assemblages at the studied sites were the highest in 2013. The basic pests of birch in the northern cities were chewing phyllophages, especially Tenthredinidae sawflies.