Structure of communities of Elateridae family of subzones of middle and southern taiga under technological environmental impact

The structure of communities of Elateridae was investigated in the regions affected by coppersmelting plants in the areas located in different ecological and geographical subzones of the taiga zone. A comparison of emission sources of the same kind in forest ecosystems of different taiga subzones allowed us to analyze changes in the structural arrangement of Elateridae complexes along the gradient of chemical pollution, to reveal adaptive mechanisms of Elateridae complexes to high industrially generated load, to observe general and specific zonal features of the reaction of click beetles to this kind of anthropogenic action. We succeeded in demonstrating that the latitudinal zoning is a base of the hierarchy of the factors that determine the structural divergence of the Elateridae communities. The hydrothermal regime of the middle taiga subzone under anthropogenic modification provides more favorable conditions for mesophile groups of pedobionts in comparison with the southern taiga.     

Structure of plant communities in the early succession stages on anthropogenic sandy outcrops of the forest tundra and northern taiga of Western Siberia

The results of a study of the taxonomic, ecological, and phytocenotic structure of plant communities formed in the early stages of overgrowth of the anthropogenic sandy outcrops within the forest-tundra zone and northern taiga forest subzone of Western Siberia are presented. In the early stages of vegetativecover restoration, there are from 2 to 11 species growing into sparse communities of the classes Loiseleurio-Vaccinietea, Artemisietea vulgaris, and Koelerio-Corynephoretea. The participation of some meso-xerophytic forest-tundra, meadow-margin, and weed herbaceous plant and dwarf shrubs species, mostly with ruderal and stress-tolerant eco-phytocenotic strategies, as well as with secondary strategies—violent-ruderal and ruderal–stress-tolerant—in the secondary succession on the sandy outcrops have been shown. The primary succession begins at the bottom and slopes of the pit ditches, as well on the surface of the sand dunes, and proceeds at an accelerated scenario. Hygro-, meso- and xerophilous species, predominantly oligo-mesotrophic rhizome and densely firm-bunch grasses and shrubs of the native flora, as well as ground lichens, participate in the early stages of succession.     

Structure and role of microbial communities in southern taiga soils

General regularities in the structure of the microbial communities of southern taiga soil ecosystems and taxonomic differences between the microbial communities of soils with different hydrothermal characteristics are discussed with reference to the main types of soils of the Central State Forest Biosphere Reserve.     

Structure and function of microbial communities in soil from the southern Taiga

General regularities in the structure of the microbial communities of southern taiga soil ecosystems and taxonomic differences between the microbial communities of soils with different hydrothermal characteristics are discussed with reference to the main types of soils of the Central State Forest Biosphere Reserve.     

The role of land-use history in driving successional pathways and its implications for the restoration of tropical forests

Secondary forests are increasingly important components of human-modified landscapes in the tropics. Successional pathways, however, can vary enormously across and within landscapes, with divergent regrowth rates, vegetation structure and species composition. While climatic and edaphic conditions drive variations across regions, land-use history plays a central role in driving alternative successional pathways within human-modified landscapes. How land use affects succession depends on its intensity, spatial extent, frequency, duration and management practices, and is mediated by a complex combination of mechanisms acting on different ecosystem components and at different spatial and temporal scales. We review the literature aiming to provide a comprehensive understanding of the mechanisms underlying the long-lasting effects of land use on tropical forest succession and to discuss its implications for forest restoration. We organize it following a framework based on the hierarchical model of succession and ecological filtering theory. This review shows that our knowledge is mostly derived from studies in Neotropical forests regenerating after abandonment of shifting cultivation or pasture systems. Vegetation is the ecological component assessed most often. Little is known regarding how the recovery of belowground processes and microbiota communities is affected by previous land-use history. In published studies, land-use history has been mostly characterized by type, without discrimination of intensity, extent, duration or frequency. We compile and discuss the metrics used to describe land-use history, aiming to facilitate future studies. The literature shows that (i) species availability to succession is affected by transformations in the landscape that affect dispersal, and by management practices and seed predation, which affect the composition and diversity of propagules on site. Once a species successfully reaches an abandoned field, its establishment and performance are dependent on resistance to management practices, tolerance to (modified) soil conditions, herbivory, competition with weeds and invasive species, and facilitation by remnant trees. (ii) Structural and compositional divergences at early stages of succession remain for decades, suggesting that early communities play an important role in governing further ecosystem functioning and processes during succession. Management interventions at early stages could help enhance recovery rates and manipulate successional pathways. (iii) The combination of local and landscape conditions defines the limitations to succession and therefore the potential for natural regeneration to restore ecosystem properties effectively. The knowledge summarized here could enable the identification of conditions in which natural regeneration could efficiently promote forest restoration, and where specific management practices are required to foster succession. Finally, characterization of the landscape context and previous land-use history is essential to understand the limitations to succession and therefore to define cost-effective restoration strategies. Advancing knowledge on these two aspects is key for finding generalizable relations that will increase the predictability of succession and the efficiency of forest restoration under different landscape contexts.     

Long-term dynamics and structure of shrews association (Soricidiae) in the mountain taiga of the Eastern Sayan

The dynamics of shrews association in the mountain taiga of the Eastern Sayan was considered during the years 1981 to 2010. The work was carried out in the territory of “Stolby” reserve. The structure of the association, the duration of cyclic changes of different species, effect of succession and climatic processes on the composition and structure of the community have been studied.     

Spontaneous regeneration of dry grasslands on set-aside fields

Dry grasslands are among the most threatened plant communities of Central Europe. We explore the time scale of spontaneous regeneration of dry grasslands on abandoned fields in an area of Central Europe, where also ancient grassland communities occur (Saxony-Anhalt, Germany). On three permanent plots with shallow soils we monitored during 10 years change of species composition and analysed whether spontaneous succession leads to assemblages similar to the ancient dry grassland communities in the direct surroundings. We found that dry grassland species are able to invade the permanent plots and during the 10 years of succession the number of dry grassland species increased. But even after 10 years there was a clear difference between ancient dry grassland communities and the assemblages on the permanent plots. Our findings suggest two important conclusions: First, spontaneous succession on abandoned fields is a cheap possibility for the conservation of some dry grassland species, at least on shallow soils. Second, the time scale of the regeneration process, however, is rather long. Hence, conservation of remnants of ancient grassland communities needs special attention.     

Effects of forest regeneration on the structure of bird communities in northern Finland

Breeding bird communities in five stages of secondary forest succession were studied in northeastern Finland in 1980–82. Three groups of communities were distinguished: open land, brush phase and forest communities, dominated by Motacilla alba and Oenanthe oenanthe, Phylloscopus trochilus and Anthus trivialis, Phylloscopus trochilus and Fringilla montifringilla , respectively.
Pair density, number of species, biomass of adult birds and species diversity increased in the course of succession, none of these, however, monotonously. Average bird weight showed a decreasing trend although the variation was considerable. The degree of specialization in communities (measured by ratios derived from numbers of species, genera and families) increased in the course of succession with the exception that the initial stage had relatively high values. Species nesting and feeding in trees and shrubs increased in numbers during forest regeneration whereas species nesting and feeding on the ground showed the opposite trend. The proportions of hole-nesting and sedentary species increased with increasing forest age.
The initial stages of forest succession in the north are occupied by specialized open habitat species breeding originally on open bogs and shores. These communities thus clearly differ from those predicted from the general theory of succession, which postulates that the pioneer stages of succession are dominated by habitat generalists and that these communities should have relatively low values of community diversity.     

The trophic structure of macrozoobenthos in marsh water bodies of the forest-steppe zone in the Middle Russian Hills

The trophic structure of macrozoobenthos was studied in a lake and three marshes of different succession stages. Trophic groups and guilds of macrobethic communities are found. A comparative analysis was made of trophic diversity, structure, and the distribution of trophic groups in different marsh hydrobiocenoses under secondary steppe conditions of the Zorinsky part of the Central Chernozem Reserve.     

海南岛尖峰岭热带山地雨林采伐迹地更新群落的初步分析

 海南岛西南部热带山地雨林采伐迹地上的更新群落大多数是以闽粤栲占优势的森林植被。本文以尖峰岭为例,对热带山地雨林不同采伐方式迹地上更新的群落进行了群落数量特征、种群年龄结构的分析。同时从林业生产的角度,评定了群落的更新质量,并提出了热带山地雨林适宜的采伐方式和群落更新的抚育管理方法。     

Ground vegetation in the Mongolian taiga forest‐steppe ecotone does not offer evidence for the human origin of grasslands

Question: Is the vegetation of meadow and mountain steppes distinct from the ground vegetation of light taiga forests in the transitional zone between these biomes? Location: Western Khentey Mountains, northern Mongolia. Methods: Vegetation was recorded from 100‐m² plots from all dominant types of light taiga forest and dry grassland. Distinctness of ground vegetation was studied with Detrended Correspondence Analysis (DCA). Results: Ground vegetation in the light taiga was significantly different from the herbal vegetation of meadow and mountain steppes. Clear separation was only absent for the Car ex amgunensis meadow steppes that occur in a narrow strip along the forest edge and are partly shaded by trees. Forest and steppe communities followed a moisture gradient according to the DCA ordination with light taiga forests at the moistest sites and steppe communities at the driest sites. Ulmus pumila open woodlands diverged from this pattern, because of their close spatial and phytosociological relationship to mountain steppes. Conclusions: The present results do not support the assumption that grasslands in Mongolia's transitional zone between forest and steppe would generally resemble the ground vegetation of light taiga forests. This contradicts a published hypothesis stating that the vegetation of meadow and mountain steppes would not clearly differ from ground vegetation of light taiga forests in the forest‐steppe transitional zone of Mongolia.     

The dynamics of the dune vegetation on the Polish Baltic coast

This paper deals with the Baltic coastline in Poland. Features of the climate, geomorphology, substratum, soils and vegetation are outlined. The historical forest succession is based on the results of palynological studies of fossil soils. The present-day dynamics of the plant communities are examined from the viewpoint of primary succession, regression, regeneration and secondary succession. The primary succession on moving dunes is described with particular reference to deflation fields. Attention is drawn to the spatial changes in the communities from the 16th to the 20th century as a result of natural and human factors. This study shows that during the 19th and 20th centuries and especially in the last 25 years, the dynamics of the dunes and their vegetation have been much reduced, owing to the widespread stabilization of the substratum by forests and the ongoing abrasion of the coastal dunes.     

不同放牧强度下高寒草甸植被演替规律的数量分析

 本文采用数量分析方法,研究了不同放牧强度下高寒草甸植被的演替规律。聚类分析的结果,当相关系数R>0.850时,组成群落的24种植物聚合为6类,它们分别属于植物群落不同演替阶段的建群种,优势种或主要伴生种,当R>0.870时,6个放牧强度下的群落聚合为2类,分别属于以禾草植物为共建种的两层结构的植物群落和以矮嵩草(Kobresia humilis)以及 杂类草为共建种的单层结构的植物群落。     

Patterns of plant species diversity during succession under different disturbance regimes

Summary I suggest that between-community variations in diversity patterns during succession in plant communities are due to the effects of selection on life history strategies under different disturbance regimes. Natural disturbances to plant communities are simultaneously a source of mortality for some individuals and a source of establishment sites for others. The plant community consists of a mosaic of disturbance patches (gaps) of different environmental conditions. The composition of the mosaic is described by the size-frequency distribution of the gaps and is dependent on the rates and scales of disturbance. The life-history strategies of plant species dependent on some form of disturbance for establishment of propagules should reflect this size-frequency distribution of disturbance patches. An extension of island biogeographic theory to encompass relative habitat area predicts that a community should be most rich in species adapted to growth and establishment in the spatially most common patch types. Changes in species diversity during succession following large scale disturbance reflect the prevalent life history patterns under historically common disturbance regimes. Communities in which the greatest patch area is in large-scale clearings (e.g. following fire) are most diverse in species establishing seedlings in xeric, high light conditions. Species diversity decreases during succession. Communities in which such large patches are rare are characterized by a large number of species that reach the canopy through small gaps and realtively few which regenerate in the large clearings. Diversity increases during succession following a large scale disturbance.Evidence from communities characterized by different disturbance regimes is summarized from the literature. This hypothesis provides an evolutionary mechanism with which to examine the changes in plant community structure during succession. Diversity peaks occurring at intermediate levels of disturbance as discussed by Connell and Huston are interpreted in this context.     

昆明西山半湿润常绿阔叶林及其〖HJ*3〗〖HJ*2〗次生演替群落的更新特征

对昆明西山国家森林公园处于不同演替阶段的云南油杉林、云南油杉-滇青冈混交林和滇青冈林内木本植物幼苗的种类组成、数量及更新方式等进行了调查分析。结果表明:在所调查的共144个25m2的样方中,共记录到木本植物幼苗32科45属共49种。随着演替的进行,幼苗总密度表现出先增加后降低的趋势,处于演替中期的云南油杉-滇青冈混交林内幼苗最丰富,平均密度达80株.25m-2。在不同演替阶段各植被类型中,实生和萌生两种更新方式同时存在,单一的更新方式可能使群落的更新面临较大的风险。幼苗发生了顶死或梢枯后,从其根颈处生出多个萌枝形成多干基株的更新方式结合了实生和萌生更新各自的优点,是幼苗在与环境长期作用过程中进化出的一种有效对策。     

Restored meadow harvestman communities (Opiliones) in the Bílé Karpaty Protected Landscape Area, Czech Republic

Harvestman communities inhabiting plots treated differently for grassland restoration were investigated at the Vyzkum site near Malá Vrbka village (Bílé Karpaty Protected Landscape Area). Harvestman were sampled by pitfall trapping from 1999 to 2003 on plots sown with native haymeadow seed mixture, also on plots where narrow strips of regional seed mixtures were sown either within a matrix of commercial grass mixture or within vegetation cover in natural regeneration state and on plots in a natural regeneration state. Additionally, harvestman were collected in a field under permanent crop rotation and in a neighbouring xerothermic deciduous forest. In total, 5,086 individuals of harvestman representing 15 species from three families were obtained. Phalangium opilio was dominant (78%) and P. opilio, Rilaena triangularis and Zachaeus crista were the most frequent species. The results confirmed colonisation and subsequent development of harvestman communities on meadows in various state of restoration, including plots with spontaneous plant succession. Nevertheless, biotope character and successive formation of plant cover evidently influenced the structure of harvestman communities. The highest number of taxa (12) was recorded on plots with natural regeneration; the lowest one (9) was recorded in the field with permanent crop rotation. The highest values of diversity and equitability indices of harvestman communities were found in neighbouring forest habitats representing possible sources of harvestman migration.     

Litter and soil arthropod colonization in reforested semi‐deciduous seasonal Atlantic forests

The recovery of soil ecological processes during the restoration of tropical forests is greatly influenced by arthropods that live in the litter and soil. However, these communities present complex dynamics, and their colonization patterns are not well understood. In this study, we examined the response patterns of litter and soil arthropods to the ecosystem regeneration process by assessing reforestation sites from two regions of São Paulo State, Brazil, and we compared the data obtained from these sites with data from mature forests. We assessed the arthropod communities using similarity indices and high‐level taxa abundance, with the level of forest succession and the locations of the restoration areas as factors. Forest succession correlated with the species composition as communities from the reforestation sites gradually became more similar to communities from the mature forests, while their quantitative patterns were minimally related. Forest maturation positively affected the richness of the litter community and the abundance of some minor groups, such as Protura, Diplura, and Symphyla. The region influenced the species composition but did not influence the manner in which the communities changed during the maturation process. We also found a convergent soil colonization pattern as arthropod communities from different sites became more similar during forest succession. This finding is consistent with both empirical data and theoretical predictions from the specialized literature, although the subject has been poorly explored until now. We conclude that reforestation allows the colonization of soil and litter fauna in a biased manner.     

Convergence of community composition during secondary succession on Zokor rodent mounds on the Tibetan Plateau

Aims The community succession theory is much debated in ecology. We studied succession on Zokor rodent mounds on the Tibetan Plateau to address several fundamental questions, among them: (i) During secondary succession, does the community composition converge towards one community state or multiple states depending on the initial colonization? (ii) Do mound communities located in different background communities exhibit different assembly trajectories?Methods In a sub-alpine meadow, we investigated a total of 80 mound communities at several successional stages in three different background communities resulting from different management histories and compared their changes in species composition. The distribution of plant communities over time was analyzed with quantitative classification and ordination methods. The co-occurrence patterns of species were evaluated at each successional stage, and the degree of convergence/divergence among communities was obtained by calculating two beta-diversity indices.Important findings During secondary succession, species richness of mound communities changed over time, and this change was dependent on the background community. Five life-form groups exhibited different dynamic patterns in species richness and plant cover. Community composition and the degree of species co-occurrence between communities increased over time since disturbance. There was much variation in species composition at earlier stages of succession, but communities on older mounds became more similar to each other and to their surrounding vegetation over the course of secondary succession. Post-disturbance succession of Zokor mound communities transitioned from 'multiple alternative states' to 'background-based deterministic community assembly' over time. Tradeoffs between competition and colonization, as well as the characteristics of different life-forms and mass effects within a limited species pool are the mechanisms responsible for convergence of mound communities.     

Soil and plant factors driving the community of soil-borne microorganisms across chronosequences of secondary succession of chalk grasslands with a neutral pH

Although soil pH has been shown to be an important factor driving microbial communities, relatively little is known about the other potentially important factors that shape soil-borne microbial community structure. This study examined plant and microbial communities across a series of neutral pH fields (pH=7.0-7.5) representing a chronosequence of secondary succession after former arable fields were taken out of production. These fields ranged from 17 to >66 years since the time of abandonment, and an adjacent arable field was included as a reference. Hierarchical clustering analysis, nonmetric multidimensional scaling and analysis of similarity of 52 different plant species showed that the plant community composition was significantly different in the different chronosequences, and that plant species richness and diversity increased with time since abandonment. The microbial community structure, as analyzed by phylogenetic microarrays (PhyloChips), was significantly different in arable field and the early succession stage, but no distinct microbial communities were observed for the intermediate and the late succession stages. The most determinant factors in shaping the soil-borne microbial communities were phosphorous and NH(4)(+). Plant community composition and diversity did not have a significant effect on the belowground microbial community structure or diversity.     

Diversity and anatomic structure of ectomycorrhizas of <Emphasis Type="Italic">Picea obovata</Emphasis> in the altitudinal gradient (the Denezhkin Kamen’ mountain ridge,Central Urals)

Diversity and anatomic structure of ectomycorrhizas of the Siberian spruce in natural communities over the altitudinal gradient from 305 to 800 m above sea level (northern taiga, the Denezhkin Kamen’ mountain ridge, the Central Urals) have been investigated. It is established that the relative abundance of fungal mantles of different structure changes substantially with altitude. The cross size of mycorrhizal tips and proportions of their structural parts (fungal mantle, layer of the root cortex parenchyma, and central cylinder) change insignificantly.