Seed predation is an important biotic filter that can influence abundance and spatial distributions of native species through differential effects on recruitment. This filter may also influence the ...relative abundance of nonnative plants within habitats and the communities' susceptibility to invasion via differences in granivore identity, abundance, and food preference. We evaluated the effect of postdispersal seed predators on the establishment of invasive, naturalized, and native species within and between adjacent forest and steppe communities of eastern Washington, USA that differ in severity of plant invasion. Seed removal from trays placed within guild‐specific exclosures revealed that small mammals were the dominant seed predators in both forest and steppe. Seeds of invasive species (Bromus tectorum, Cirsium arvense) were removed significantly less than the seeds of native (Pseudoroegneria spicata, Balsamorhiza sagittata) and naturalized (Secale cereale, Centaurea cyanus) species. Seed predation limited seedling emergence and establishment in both communities in the absence of competition in a pattern reflecting natural plant abundance: S. cereale was most suppressed, B. tectorum was least suppressed, and P. spicata was suppressed at an intermediate level. Furthermore, seed predation reduced the residual seed bank for all species. Seed mass correlated with seed removal rates in the forest and their subsequent effects on plant recruitment; larger seeds were removed at higher rates than smaller seeds. Our vegetation surveys indicate higher densities and canopy cover of nonnative species occur in the steppe compared with the forest understory, suggesting the steppe may be more susceptible to invasion. Seed predation alone, however, did not result in significant differences in establishment for any species between these communities, presumably due to similar total small‐mammal abundance between communities. Consequently, preferential seed predation by small mammals predicts plant establishment for our test species within these communities but not between them. Accumulating evidence suggests that seed predation can be an important biotic filter affecting plant establishment via differences in consumer preferences and abundance with important ramifications for plant invasions and in situ community assembly.
Floodplain ecosystems take on the role of active areas of biodiversity and provide many “ecosystem services”, as evidenced by a number of European scientific references. A biodiversity analysis of ...river floodplains in six European countries within the temperate zone has shown that the floodplains are habitats with a high-level of structural and functional dynamics. The level of their conservation reflects the floristic diversity of forest territories, which is especially important for subarid areas. Recently, a comparison of bioecological characteristics of flora in floodplain forest areas and treeless territories was conducted on the floodplain landscapes of a subarid region of Europe. The valley-terraced landscape of the Samara River, a tributary of the Dnieper can serve as a reference site of native plant complexes of subarid territory in Eastern Europe. Despite long-term anthropogenic transformation, the landscape has retained a significant phytodiversity level. The flora of the Samara River area includes 887 plant species. Of these, 177 species belonging to the rare and endangered categories. The floodplain landscape is the richest in species and most diverse part of this complex. The flora of the Samara floodplain includes 728 species (including 132 rare ones), of which 631 grow in forest communities, and 487 – in anthropogenically transformed, treeless floodplain areas. As part of the forest flora, the number of tree and shrubby species, scyophytes, hygrophytes, and megatrophs significantly increases compared to treeless sites, and the number of ruderal plant species decreases. The floristic composition of the floodplain forests of the subarid region is much richer and more diverse than the flora of the treeless floodplain areas, and this should encourage measures for their protection and restoration. Afforestation of floodplain territories within the steppe zone of Ukraine should be a priority in comparison with other landscapes. For the protection of the flora studied, a scientific justification for creating the National Park "Samara Bor" was prepared. Under the conditions of anthropogenic and climatic impact, this article is of great global importance for attracting the attention of specialists, authorities and society to the protection and restoration of biodiversity in the most valuable landscapes.
Forest plant communities of the Earth are one of the grounding factors influencing the global carbon cycle in the context of global climate change, as they are not only a source of carbon emissions ...from autotrophic respiration and oxidation of organic matter but also provide its intensive sequestration from the atmosphere in the course of photosynthesis. The natural dimension of this process is the net primary production of forest ecosystems. The research object is the features of the bioproduction process in forest plant communities of the Ukrainian Carpathians. The subject of research is the peculiarities of net forests primary production formation in different site conditions of the Carpathian National Nature Park. The purpose of the research is to carry out a comprehensive quantitative assessment of net primary production and features of the intensity of organic matter production by forest plant communities in different types of forest site condition. The assessment based on the application of the «semi-empirical» method, which considers the ecosystem net primary production of a certain age as an analogy to the current annual increment in total live biomass production. The basis for the assessment is comprised of stand-level characteristics of forests and mathematical tools based on data collected at 80 temporary sample plots. The forests of the Carpathian National Nature Park produce annually almost 360 thousand tons of plant organic matter. At the same time, the average density of net primary production of the studied stands is more than 1000 g·(m2)-1·year-1. Spruce stands produce almost 75 % of the production of forest plant communities of the park. The peculiarities of forests’ primary production formation in the stands of different forest site conditions are determined. In particular, more than 70 % of the production is accounted for stands in moist fertile hornbeam site type, 80 % of which produced by mid-aged stands. A significant influence of the type of forest site conditions and stand productivity on the indices of organic matter production intensity by the forest stands of the park are established. The highest values of this index are inherent for stands with Ib and higher site index classes in moist fertile hornbeam site type which are at the level of 1300 g·(m2)-1·year-1. At the same time, beech stands in these forest conditions reach values of more than 1700 g·(m2)-1·year-1. Almost 55 % of the primary production of the studied forests accounts for stem wood (26.8%) and photosynthetic apparatus (27.1%). At the same time, a significant impact of the changes in forest site conditions types on the studied index fractional structure was estimated. The research results on the primary production of the Carpathian NNP forests form an information basis for forecasting their role in biosphere.
A second version of the syntaxonomical classification of calcareous Norway spruce communities is presented for the region of Slovak Western Carpathians. Recent knowledge on delimitation of natural ...Norway spruce woodlands in Slovakia is summarized as well. As result, four in Slovakia traditionally recognized associations are distinguished:
on the ecologically most extreme habitats, followed by
(a replacement for pseudonymically used
), tall-forb community of
and ca. species-poor low-forb community of
(syn.
). Additionally, two new associations are differentiated:
ass. prov. standing between
and
and acidified
on deeper soils developed over rocks of the Mráznica formation. For nomenclatural reasons, new order
is described for species-rich calcicolous communities of the class
as well as subordinated new alliance
for the supramontane calcicolous Norway spruce communities.
Aim
To date, despite their great potential biogeographical regionalization models have been mostly developed on descriptive and empirical bases. This paper aims at applying the beta‐diversity ...framework on a statistically representative data set to analytically test the consistency of the biogeographical regionalization of Italian forests.
Location
Italy.
Taxon
Vascular plants.
Methods
Forest plant communities were surveyed in 804 plots made in a statistically representative sample of forest communities made by 201 sites of Italian forests across the three biogeographical regions of the country: Alpine, Continental, and Mediterranean. We conducted an ordination analysis and an analysis of beta‐diversity, decomposing it into its turnover and nestedness components.
Results
Our results provide only partial support to the consistency of the biogeographical regionalization of Italy. While the differences in forest plant communities support the distinction between the Alpine and the other two regions, differences between Continental and Mediterranean regions had lower statistical support. Pairwise beta‐diversity and its turnover component are higher between‐ than within‐biogeographical regions. This suggests that different regional species pools contribute to assembly of local communities and that spatial distance between‐regions has a stronger effect than that within‐regions.
Main conclusions
Our findings confirm a biogeographical structure of the species pools that is captured by the biogeographical regionalization. However, nonsignificant differences between the Mediterranean and Continental biogeographical regions suggest that this biogeographical regionalization is not consistent for forest plant communities. Our results demonstrate that an analytical evaluation of species composition differences among regions using beta‐diversity analysis is a promising approach for testing the consistency of biogeographical regionalization models. This approach is recommended to provide support to the biogeographical regionalization used in some environmental conservation polices adopted by EU.
This paper aims at applying the beta‐diversity framework on a statistically representative data set to test the consistency of the biogeographical regionalization of Italian forests based on the three different regions recognised within the country. Our results provide only partial support to the consistency of the biogeographical regionalization of Italy based on three regions. Our findings support the existence of a biogeographical structure of the species pools that is captured by the biogeographical regionalization. However, nonsignificant differences between the Mediterranean and Continental biogeographical regions suggest a weakness in this biogeographical regionalization.
The relevance of the research is caused by the need to preserve the resource- and environment-reproducing functions of landscapes during their anthropogenic development. One of the factors ...contributing to the resilience of landscapes to anthropogenic loads is their ecosystem diversity. Currently, cartographic modeling methods are widely used in practice to determine ecosystem diversity, but they are not effective enough due to the lack of updated large-scale cartographic information about the ecosystem structure of the studied landscapes. The aim of the research is to develop a methodology for analyzing the ecosystem diversity of the region's landscapes using remote sensing materials and to test it on the territory of the Leningrad region. Objects: ecosystem diversity of landscapes. Methods: remote sensing of landscapes; construction of digital terrain models in the GIS environment; automated interpretation of soil and vegetation cover; statistical data processing, aerial surveys; cartographic generalizations; regional landscape and environmental analysis using GIS. Results. The expediency of using remote sensing materials to assess the ecosystem diversity of the region's landscapes is substantiated. A model of automated interpretation of the main types of forest vegetation cover based on its vegetation indices is developed; an approach to determining ecosystem diversity based on the materials of automated interpretation of the main types of forest vegetation cover is proposed. Aerial photography of fourteen key sites selected in the Leningrad region was performed using an unmanned aerial vehicle. Aerial photos were transformed using the digital photogrammetric system PHOTOMOD. A classifier of the main types of forest plant communities characteristic of the study area was developed. Vegetation indices were determined for each of them (normalized difference vegetation index and vegetation index adjusted for the underlying surface); automated decoding of the main types of forest vegetation cover in key areas was performed and the ecosystem diversity of each of them was calculated based on its results. In the GIS environment, a cartogram of the ecosystem diversity of the landscapes of the Leningrad region was compiled. Summary. The method developed by the authors can be successfully applied in the design of natural and anthropogenic systems in various regions, taking into account the specifics of their physical and geographical conditions.
•In forests, local plant response to landscape features changed with landscape extent.•Landscape features at large scale (>500m) better predicted local plant response.•A better consideration of the ...large-scale effects of landscape on plants is needed.•This may imply to take better account of time-lag effects of landscape.
Most studies of landscape effects on plants in forests have explored only relatively small landscape scales (size of spatial extent) considering the poor-dispersal ability generally reported for forest plants, or failed to verify confidently that the scales at which landscape is considered best predicts plant patterns. We investigated the effect of landscape composition on response of plant communities according to three scales - 400 ha, 100 ha and 25 ha - in 263 forests in the northern half of France. We hypothesized that landscape composition at the 400-ha scale better predicted plant responses than smaller scales. We built models to compare the effects of each scale on individual species response and plant composition of 1902 700-m2 vegetation plots, considering the shared and pure effects of scales. Only landscape composition at the 400-ha scale showed a critical pure effect on plant composition. Similarly, the 400-ha scale better predicted individual species response. Using a large dataset, we brought evidence that landscape composition further than 100 ha and at least up to 400 ha had more effects on local plant diversity in forests, which means that smaller-scale investigations may miss the influence of landscape on plant patterns. The effects of large spatial scale may reflect the legacies of past landscape or the long-distance dispersal capacity of plants. Our findings call for better consideration of the large-scale effects of landscape on plants both in scientific studies and management plans.
Introduced plant species have significant negative impacts in many ecosystems and are found in many forests around the world. Some factors linked to the distribution of introduced species include ...fragmentation and disturbance, native species richness, and climatic and physical conditions of the landscape. However, there are few data sources that enable the assessment of introduced species occupancy in native plant communities over broad regions. Vegetation data from 1,302 forest inventory plots across 24 states in northeastern and mid-western USA were used to examine and compare the distribution of introduced species in relation to forest fragmentation across ecological provinces and forest types, and to examine correlations between native and introduced species richness. There were 305 introduced species recorded, and 66 % of all forested plots had at least one introduced species. Forest edge plots had higher constancy and occupancy of introduced species than intact forest plots, but the differences varied significantly among ecological provinces and, to a lesser degree, forest types. Weak but significant positive correlations between native and introduced species richness were observed most often in intact forests.
Rosa multiflora
was the most common introduced species recorded across the region, but
Hieracium aurantiacum
and
Epipactus helleborine
were dominant in some ecological provinces. Identifying regions and forest types with high and low constancies and occupation by introduced species can help target forest stands where management actions will be the most effective. Identifying seemingly benign introduced species that are more prevalent than realized will help focus attention on newly emerging invasives.
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