Spatial-typological differentiation of the ecosystems of the West Siberian Plain. Communication II: Underground phytomass,dead organic matter,and soil humus

Similarity was quantified for the ecosystems of the West Siberian Plain based on the masses of plant cover, dead organic matter, and underground organic matter (including soil humus) and the resultant matrix was subjected to cluster analysis. The results showed that the differentiation in the vegetation was nearly equally attributable to zonal gradients of thermal and moisture conditions (waterlogging), while the differentiation in the underground part of the ecosystems was predominantly under control of waterlogging. Intratypical differences in the underground part were due to zonal-subzonal heterogeneity in the gradients of thermal and moisture conditions, composition of vegetation, and flooding during snow-melt period. Such division did not entirely agree with subzonal division. The ecosystems were rather aggregated on the basis of the three abovementioned characteristics, with flooding and forest-forming species being the same.     

Zoogeography of a South African Province: A framework for management

State‐level conservation in South Africa is structured around distinct political entities (i.e. municipalities). This is problematic because an ecological approach that considers species distribution is required to delineate meaningful management units. To do so, vegetation types can be used as management units—however, it is uncertain whether vertebrate communities are associated with vegetation types as defined by the national vegetation map. Here, we investigate mammal diversity patterns within and among biomes (savannah and grassland) and bioregions and test whether different mammal communities were associated with different vegetation types. We used an extensive database of species occurrences in the North West Province. We found that species richness was higher in the savannah than grassland biome. Beta diversity was higher within the savannah than grassland biome, due to greater environmental heterogeneity, though one grassland bioregion was similar to the savannah bioregions. Mammal communities were significantly different among bioregions, but not biomes, suggesting mammal communities are congruent with vegetation type at finer scales (i.e. bioregional), but not at coarser scales (biomes). It thus makes sense to use a bioregional framework to design mammal management strategies. The invasion of grasslands by savannah species should be monitored, specifically given the predicted changes in climate.     

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.     

Sentinel Nematodes of Land-Use Change and Restoration in Tallgrass Prairie

Changes in land use and the associated changes in land cover are recognized as the most important component of human-induced global change. Much attention has been focused on deforestation, but grasslands are among the most endangered ecosystems on Earth. The North American tallgrass prairie is a dramatic example, exhibiting a greater than 95% decline in historical area. Renewed interest in prairie conservation and restoration has highlighted the need for ecological indicators of disturbance and recovery in native systems, including the belowground component. The tallgrass prairie differs from the agricultural systems that have replaced it in having greater diversity and heterogeneity of resources, less physical soil disturbance (although other disturbances, such as fire and grazing, are prominent), and greater nitrogen limitation. Understanding the responses of nematode taxa to these characteristic differences is crucial to the development and improvement of community indices, but while knowledge of disturbance responses by individual taxa is accumulating, the level of necessary taxonomic resolution remains in question. Although nematode communities generally are better described for temperate grasslands than for other natural ecosystems, identification of sentinel taxa is further confounded by high levels of diversity, and both spatial and temporal heterogeneity.     

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.     

Classification and gradient analysis of the beech forest vegetation of the southern Rodopi (northeast Greece)

Pure and mixed beech forest vegetation of the southern Rodopi range (northeast Greece) was studied using 614 relevés and multivariate analyses (TWINSPAN and DCA). Classification of the relevés resulted in 12 vegetation units, 8 of which were ranked as associations or communities and the rest as subcommunities and variants. DCA diagrams of relevés and taxa indicated that floristic differentiation was attributed mainly to factors such as altitude (affecting temperature and humidity), soil nutrient content and substrate type (affecting physical and chemical soil properties). Differential taxa of vegetation units were chosen based on their phi coefficient values, which were calculated from three different percentage synoptic tables that corresponded to three ranks (ecological groups, associations and communities, and subcommunities and variants) of floristic differentiation. The calculation of phi coefficient on the basis of relative constancy of taxa helps to overcome the problem of the dependence of fidelity values on the number of relevés per vegetation unit and to facilitate the better investigation of the floristic differentiation even of rare vegetation units represented by a small number of relevés. Furthermore, the calculation of fidelity values for different hierarchical levels enables a more detailed and thorough investigation of the floristic differentiation of the vegetation units.     

The effect of oil extraction on ground cover of West Siberian taiga forests

The study explored the effect of oil pollution, soil salinization, and waterlogging on ground cover of green-moss forests in West Siberian middle and northern taiga. These disturbances reduce the total abundance and biological productivity of ground cover, taxonomic richness, and change roles of some species and plant groups in communities.     

Spatial-typological differentiation of ecosystems of the west siberian plain. Communication III: Terrestrial invertebrates

The spatial distribution of the terrestrial invertebrate population of the West Siberian Plain is analyzed at the level of large functional groups (soil nematodes, annelids, microarthropods, mesoarthropods, snails, grass layer arthropods). Their air-dry biomass and roles in local ecosystems are estimated. The invertebrate population was classified in two ways: after averaging over units of the vegetation map of West Siberian Plain and after averaging over groups of units of this map. A digital thematic map of the invertebrate population is produced. Special features of the spatial heterogeneity of invertebrates were identified in correlation with the vegetation and humus distribution patterns. The biomass distribution of invertebrate groups is found to be less heterogeneous but more consistent with the distribution of natural zones.     

Classification and ecology of the mid‐seral Picea mariana forests of British Columbia

Abstract. We sampled vegetation and soils of, and classified mid‐seral, even‐aged, fire‐origin, upland Picea mariana ecosystems in the Boreal White & Black Spruce and Sub‐boreal Spruce zones of British Columbia, Canada. We applied multi‐variate and tabular methods to analyse and synthesize the data from 121 plots according to the methods of biogeoclimatic ecosystem classification. We delineated seven basic vegetation units and described their vegetation and environmental features. However, the delineated units could not be related to neither of the taxonomies proposed for the North American boreal forest communities. Although species‐poor, the under‐storey vegetation in the sampled ecosystems provided for a sufficient floristic differentiation, which matched well the major edaphic differences between the units. The classification of mid‐seral boreal ecosystems may be more useful that based on old‐growth stands that are infrequent or lacking in the landscape due to wildfires.     

The structure of the vegetation of Khakasia

A diagram of the vegetation structure of Khakasia, made up with the use of a generalized large-scale map, shows the main variety of the phytocoenoses. It is particularly important for the analysis of the vegetation of mountaincous regions.Differentiated areas of phytocoenoses are used to distinguish the region borders in fractional geobotanical regionalization.Khakasia belongs to three geobotanical provinces of the Altal-Saijan geobotanical region — provinces of Minusinsk depression, West Saijan and Kuznetsk Alatau. In Khakasia, geobotanical districts are distinguished by altitudinal zonation and phytocoenotic structure. The vegetation cover is comprehensively described in a special monograph.Nomenclature follows (Flora USSR. Ed. Acad. Sc. Leningrad Vol. I–XXX, 1934–1960). This paper was presented at the International Botanical Congress, USSR, Leningrad, July 1975.     

Spatial-typological differentiation of ecosystems of the West Siberian Plain. Communication V: Terrestrial ecosystems

Results of classification of terrestrial ecosystems using an average similarity matrix are reported for the West Siberian Plain. Initial indices are first calculated separately for four components of an ecosystem. These components (blocks) include the underground block (soil humus, mortmass, and underground phytomass), above-ground vegetation, and invertebrates and vertebrates. Mismatch of boundaries in separate blocks of ecosystems and in comparison with the inhomogeneity of ecosystems in general was demonstrated. These differences are observed in both the typological and typological-chorological analysis. The indicated features of spatial succession within the blocks generate continuity of ecosystems and the conventional character of all the classifications and drawn boundaries.     

Composition and structure of spruce forests of the southwestern part of Moscow region

Coenotic features of boreal, nemoral, and subnemoral spruce stands of the southwestern part of Moscow region have been studied using ground-based and remote sensing data. Despite significant modifications of the vegetation cover in the region due to human impacts, the species composition of the spruce communities still retains typical zonal features of the regional vegetation and is associated with certain landscape elements. Cartographic modeling has allowed us to identify the spatial distribution patterns for various spruce forest types and produce a series of geobotanical maps (scale 1: 100000). The ecophytocoenotic approach was used for classifying the forest vegetation. An analysis of the spatial differentiation of the forest cover—using spruce forests with different species composition as an example—has confirmed the ecotonal structure of the study area demonstrated through a characteristic latitudinal distribution of geoecolological spectra of species.     

Space-time impact of fire events on swamp-forest ecosystems of the west Siberian Plain

An analysis of information on the groundwater dynamics, frequency of fire events, and postfire progressive-age stages of vegetation in the swamp-forest ecosystems of the southern taiga and forest-steppe zone of the West Siberian Plain has shown that fire events are a permanent factor that controls the scales and dynamics of the forest and swamp formation processes under these specific conditions in the modern era. The greatest influence on the dynamics of ecosystems is exerted by the frequency of fires. The scope and depth of the transformation of swamp ecosystems affected by the pyrogenic factor are due to their environmental regimes and have their own properties in different landscapes.     

人工固沙植被恢复对地表节肢动物群落组成及多样性的影响

人工绿洲是干旱区主要的自然景观之一,为了维护绿洲稳定而营建的防护林强烈改变地表生态水文过程,进而影响着地上和地下生物多样性。然而,以往的研究对地上植被关注较多,而对土壤动物研究较少。以张掖绿洲外围人工固沙植被群落和天然固沙植被群落为研究对象,探讨人工固沙植被恢复对荒漠地表节肢动物群落组成及多样性的影响及不同动物类群对植被变化的响应模式。研究表明,天然固沙植被群落转变为人工固沙植被群落显著降低了地表节肢动物数量,但提高了地表节肢动物类群丰富度和多样性,这在5月份表现尤为明显。植被类型对地表节肢动物群落的影响不同,8月人工柽柳林群落地表节肢动物活动密度、类群丰富度和多样性均显著高于人工梭梭林群落。人工固沙植被恢复显著降低了适应荒漠环境的拟步甲科甲虫,而蚁科和部分蜘蛛的数量显著增加,它们对人工固沙植被恢复的响应模式不同决定了群落结构及多样性的变化规律。此外,研究还发现一些地表节肢动物类群对不同生境具有强烈的指示作用,如拟步甲科等可指示荒漠生境,潮虫科等可指示梭梭林生境,而蠼螋科和狼蛛科等可指示柽柳林生境。综上所述,人工栽植固沙灌木形成的固沙植被群落导致了一些适应荒漠环境的地表节肢动物类群的数量降低,但也为更多的地表节肢动物类群提供了适应栖居环境和充足的食物资源等,从而提高了地表节肢动物的多样性。     

Spatial distribution of young forests and carbon fluxes within recent disturbances in Russia

Forest stand age plays a major role in regulating carbon fluxes in boreal and temperate ecosystems. Young boreal forests represent a relatively small but persistent source of carbon to the atmosphere over 30 years after disturbance, while temperate forests switch from a substantial source over the first 10 years to a notable sink until they reach maturity. Russian forests are the largest contiguous forest belt in the world that accounts for 17% of the global forest cover; however, despite its critical role in controlling global carbon cycle, little is known about spatial patterns of young forest distribution across Russia as a whole, particularly before the year 2000. Here, we present a map of young (0–27 years of age) forests, where 12‐ to 27‐year‐old forests were modeled from the single‐date 500 m satellite record and augmented with the 0‐ to 11‐year‐old forest map aggregated from the 30 m resolution contemporary record between 2001 and 2012. The map captures the distribution of forests with the overall accuracy exceeding 85% within three largest bioclimatic vegetation zones (northern, middle, and southern taiga), although mapping accuracy for disturbed classes was generally low (the highest of 31% for user's and producer's accuracy for the 12–27 age class and the maximum of 74% for user's and 32% for producer's accuracy for the 0–11 age class). The results show that 75.5 ± 17.6 Mha (roughly 9%) of Russian forests were younger than 30 years of age at the end of 2012. The majority of these 47 ± 4.7 Mha (62%) were distributed across the middle taiga bioclimatic zone. Based on the published estimates of net ecosystem production (NEP) and the produced map of young forests, this study estimates that young Russian forests represent a total sink of carbon at the rate of 1.26 Tg C yr^?1.     

Spatial scaling of arbuscular mycorrhizal fungal diversity is affected by farming practice

Evidence suggests that microbial communities show patterns of spatial scaling which can be driven by geographical distance and environmental heterogeneity. Here we demonstrate that human management can have a major impact on microbial distribution patterns at both the local and landscape scale. Mycorrhizal fungi are vital components of terrestrial ecosystems, forming a mutualistic symbiosis with plant roots which has a major impact on above ground ecology and productivity. We used contrasting agricultural systems to investigate the spatial scaling of the most widespread mycorrhizal fungus group, the arbuscular mycorrhizal fungi (AMF). Using multiple sampling sites with a maximum separation of 250 km we describe for the first time the roles which land management, environmental heterogeneity and geographical distance play in determining spatial patterns of microbial distribution. Analysis of AMF taxa–area relationships at each sampling site revealed that AMF diversity and spatial turnover was greater under organic relative to conventional farm management. At the regional scale (250 km) distance–decay analyses showed that there was significant change in AMF community composition with distance, and that this was greater under organic relative to conventional management. Environmental heterogeneity was found to be the major factor determining turnover of AMF taxa at the landscape scale. Overall we demonstrate that human management can play a key role in determining the turnover of microbial communities at both the local and regional scales.     

Ecological structure of vegetation cover of taiga and alpine territory: Detection and representation of basic peculiarities by the mapping method

The geobotanical mapping of territory in the upper reaches of the Bureya River was carried out. Zonality, general diversity, and territorial ratio of vegetation classes, as well as location on relief (landscape) and dynamic vegetation series, are represented on the map of actual vegetation cover. Mapping as a research method, as a rule, leads to a higher level of understanding of basic peculiarities of an object. The map as a result of research reflects clearly basic peculiarities of an object in accordance with the map scale or demonstrably shows the shortcomings of the conducted study.     

Statistical methods for analysis of communities' species structure (with riverine macrozoobenthos as an example)

Species turnover or coherence in species co-occurrence as well as boundary clumping and nestedness in structural composition of ecological communities reflect the extent of determinancy in their organization (Leibold, Mikkelson, 2002). These phenomena may be a consequence of either interactions between species or heterogeneity in spatial distribution of populations density. We have examined statistical patterns of species structure variability using benthic communities of riverine ecosystems as an example. The ecosystems studied are characterized by strongly pronounced linear gradient of landscape features and environmental factors. The results of a long-term hydrobiological survey being conducted at 22 observational stations on the Sok River along with its tributary, the Baytugan River (Lower Volga basin, total watercourse length is 375 km) are involved into the analysis. A spreadsheet for statistical processing of the data included 375 macrozoobenthic taxa contained in 147 samples. An assessment of species structure nestedness in benthic communities at separate sites and along the watercourse as a whole has been carried out using various metrics such as nestedness "temperature" (Patterson, Atmar, 2000), discrepancy measure (Brualdi, Sanderson, 1999), nestedness based on overlap and decreasing fill (NODE--Almeida-Neto et al., 2008) and others. Statistical significance of ecosystems structural determinancy has been tested by means of randomization procedures and standard null models (Gotelli, 2000). The conclusions seem to be ambiguous and dependent on a level and scale of an ecosystem resolution into separate blocks, also on configuration and completion of initial bio-geographical tables. A searching for reliable and representative criteria of nestedness, invariant to various non-ecological modifications of the matrices but sensitive to estimation of analyzed ecological processes and suitable for comparisons of communities, is clearly needed. A quantitative estimation of species turnover and coherence in species cooccurrence has been performed using different indices of unique combinations and checkerboard score (Stone, Roberts, 1992) as well as Schluter's variance test. By means of empirical Bayesian approach (Gotelli, Ulrich, 2010) records of species pairwise combinations are formed where the frequency of species co-occurrence cannot be interpreted as a random value. Positive and negative relationships between taxa in macrozoobenthic communities, which are found out to be statistically significant, in most cases can be explained as being not the consequence of competition for resources but of spatial heterogeneity of biotopical conditions along the whole length of the watercourse.     

Static and dynamic approaches to landscape heterogeneity in the Hungarian forest‐steppe zone

Abstract. This paper describes the successional status of the vegetation in a clear‐felled dry oak woodland at the edge of the Hungarian forest‐steppe zone on the basis of a vegetation map. Due to a varied geomorphology of the colline landscape several so‐called landscape units can be distinguished. The patchwork on the vegetation map is evaluated using several, morphology‐based attributes (static morphological indices) traditionally applied in landscape ecology. In the ca. 100 years that elapsed since forest clear‐cut, xeric grassland species and steppe elements became more abundant and the former xeromesophilous vegetation – containing even some woodland components – is slowly turning into xeric grassland communities. The vegetation units mapped can be arranged into a hypothetical succession scheme in which successional distances (the number of steps between two stages) are determined. Based on the distances thus obtained, a new dynamic morphological index is introduced. This is applied to each landscape unit for the dynamic evaluation of successional vegetation, its results being compared with those obtained by static morphological indices.     

An ecological map of Europe: why and how?

After a recall of the recent emergence of the great ecological problems on the scale of the European continent and of the privileged use of vegetation maps as an ecological tool, a cartographic synthesis of the main plant formations in Europe is submitted on the basis of a hierarchized and numerized nomenclature of the vegetation units. Examples of connections between vegetation and ecology, as suggested or facilitated by this map, are given: use of the monthly ombrothermic diagrams as a privileged tool, thermic limits of the boreal zone, indicative value of the Mediterranean xerothermic area, predictive models of the geographical shifts of the great ecosystems according to the expected climate changes.