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In this paper we present an implementation of the natural capital index (NCI), a highly aggregated policy-relevant biodiversity indicator for Hungary, based on the MÉTA database, a detailed field-based vegetation database with a habitat quality attribute. To this end, we introduce two different weighting schemes for the field-estimated MÉTA values, both rooted in the concept of ecosystem services: a linear “equal steps” (NCI lin ) and an exponential (NCI exp ) weighting scheme. The natural capital index of Hungary and its physical geographical regions are calculated and presented from both aspects. The national NCI lin is 9.9% (indicating an overall 90% loss in the availability of the major supporting ecosystem services), and NCI exp is 3.2% (indicating an even greater degree of loss in terms of the conservation of rare species). The geographical regions of Hungary exhibit considerable spatial variation, which reveals important information on their basic characteristics (e.g. agricultural potential) and land use history. As NCI can be calculated on any spatial scales from local to national, this indicator may become a useful tool for policy development and evaluation purposes, including environmental impact assessments (EIA) and strategic environmental assessments (SEI). However, due to several conceptual limitations (e.g. disregard for rarity, spatial structure and cultural values, questions of recency and repetition) NCI should not be regarded as a self-sufficient universal tool, and strategic decisions should be based on careful consideration of all potentially relevant factors.

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We review the population ecology of Allium ursinum according to its life history, phenology, demography, dispersal, and population dynamics. Spatial distribution is reviewed on two spatial scales. First, on a broad scale over Europe, in relation to the habitat requirement of the species. Second, on a fine scale of individual patches, presenting some results about the local processes of density regulation and patch formation. We conclude that A. ursinum has a distinct, hitherto non-described, strategy for monopolizing space and dominating the forest floor. This Clan-of-Clones strategy has the following attributes. 1) Most of the seeds are dispersed close to the parent. 2) Seedling establishment is facilitated by the surrounding adults. 3) Allocation to vegetative reproduction is relatively small; its main role is to prolong local persistence. 4) The genet is not integrated physiologically, except for a transient connection between parent and offspring. An important consequence of the Clan-of-Clones strategy is that occupied patches can be fine-grained mosaics in terms of genetic composition and age groups.

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Spiders contribute essentially to the arthropod community of forests and are known to be distributed in non-random pattern according to environmental, structural, competitive, and predacious conditions. The aim of the study was to investigate the effects of the distance to trees on the distribution pattern of soil-dwelling spiders. We verified the hypothesis that stem-close and stem-distant microhabitats differ with respect to taxonomical and ecological characteristics of spider assemblages, hence, functional significance on a small spatial scale. Ground-dwelling spiders were collected with pitfall traps in positions close (20–30 cm) and distant (2 m) to the stem bases in mature forests of different stand types (spruce, Douglas fir, beech-spruce, oak-beech). To identify significant drivers of spider assemblage composition, environmental parameters were assessed in relation with the arrangement of pitfall traps. The study documented significant variability in the composition of spider assemblages of stem-close and stem-distant pitfall traps within each of the study sites. The position of traps strongly affected species richness, species composition, activity density, and dominance structure. Thus, sampling at both positions revealed that the species richness of spiders is spatially restricted. Moreover, spider assemblage structure differed in the classification of species to size and ecological preference. Those results implicate potential consequences for their functional role in forests in relation to the distance to the trees.

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Community ecologists have become increasingly interested in analyzing the phylogenetic diversity of species assemblages. Species that co-occur in the same habitats often share a common phylogenetic history such that at coarse spatial scales a species assemblage with a locally clustered phylogenetic structure is usually associated with the presence of habitat filtering mechanisms. However, more recently it has been hypothesized that environmental filters act primarily on the relative abundance of species rather than on their simple presences and absences, reducing the species’ probabilities to persist in given environmental conditions. This process may produce a non-random distribution of species abundances in the regional phylogeny even in the absence of a locally clustered phylogenetic structure. In this paper, using data from the urban flora of Brussels (Belgium) we tested for the presence of non-randomness in the distribution of abundances among the species phylogenetic structure. We argue that the observed pattern of low species phylogenetic distinctiveness at increasing species abundances is compatible with environmental filtering processes.

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Stand and leaf scale responses of loess grassland swards to elevated air CO 2 concentration had been investigated in a mini FACE system during 1998–2000. The study concentrated on biomass, leaf area index (LAI) and vegetation surface temperature (stand scale) and on diurnal carbohydrate pattern and gas-exchange responses (leaf scale). Leaf net CO 2 uptake under prolonged exposure to elevated CO 2 showed an upward response in the dicotyledonous and a downward one in the monocotyledonous species. Dawn and evening carbohydrate levels in leaves suggested growth stimulation of the dicot under elevated CO 2 and the opposite for the grass species and indicated sink limitation as a major factor determining photosynthetic acclimation at the species level. The smaller LAI as well as the insignificant biomass response to elevated air CO 2 was a compounded response by multi-species stands. Under mild water shortage, elevated air CO 2 concentration partly alleviated the drought effect shown by the higher relative growth rate of LAI. Canopy surface temperatures of the vegetation in the CO 2 enriched rings were higher than those in the ambient rings suggesting that decreased leaf conductance and transpiration were responsible for the temperature difference between the treatments. Increased canopy surface temperature under elevated air CO 2 concentration will probably lead to increased sensible heat flux and therefore enhanced convection at larger spatial scales.

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Abstract

Terrestrial ecosystems across the world experience large-scale and widespread urbanization, causing a sharp decline, fragmentation and segregation of natural landscapes. Nevertheless, fragments of natural habitats that are found within the largest cities may still be capable of preserving high species diversity that amount to a large portion of the regional biodiversity. Knowing which variables of the urban landscape promote the conservation of species' assemblages in large cities helps us to implement measures that support biodiversity conservation. We sampled the butterfly assemblages of eight urban forest fragments in Curitiba (Southern Brazil), from September 2015 to April 2016. At each site, richness, diversity and composition of butterflies were estimated and then correlated to nine landscape variables measured at two spatial scales (buffers of 250 and 750m). A total of 298 species were recorded in these fragments, representing 53.7% of all species known to occur in the city. Despite of great difference in the size of the fragments (between 27 and 56.3 ha), there were no significant differences in species richness among the fragments. On the other hand, some significant correlations were observed between landscape variables and butterfly composition other than the fragment itself, such as the paved area and total forested area present around the fragments. These results reinforce the idea that the conservation of natural fragments in urban areas requires public policies that enhance not only the habitat quality of the fragment itself, but also enrichment of the landscape around them.

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The on-going Biodiversity Monitoring in Switzerland Programme (BDM) has monitored vascular-plant species richness since 2001. This long-term programme focuses on two indicators at different spatial scales. First, the local diversity indicator monitors changes of species richness within habitats or types of land use (within-habitat diversity). Second, the landscape diversity indicator is utilized to describe landscape diversity (i.e., within-habitat mosaic diversity). Here we examine if the reproducibility of the BDM methods is sufficiently precise to detect future changes in species richness. We demonstrate that systematic methodical errors are negligible. Random errors that make changes more difficult to detect are also small. We calculate the Minimum Detectable Difference (MDD) for selected BDM strata using the variance of measured values. Then we deduce the MDD values for paired samples using data from grasslands and forests in the Canton Argovia. With 2.4 and 1.6 species they are promisingly precise. We develop a simple scenario for possible changes in species richness and show that they surpass the deduced MDD values by a factor four to six. We conclude that the BDM methods are appropriate for detecting future changes in species richness.

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Ad hoc decisions during fieldwork reduce the accuracy and reliability of vegetation maps. A method is proposed to objectify vegetation (thematic aspects) mapping (spatial aspects) for monitoring (temporal aspects). The most accurate and reliable description of the vegetation is a list of all plant species found within a plot. Therefore, the proposed method is an interpolation of a spatially representative sample of permanent plots combined with aerial photo interpretation. The method is objective because surveyors do not have to make decisions during fieldwork based on their personal judgement. Moreover, it is flexible, because the classification and interpolation methods can be adapted to specific views or needs depending on the aim of a study. The method was applied to an area in the north of the Netherlands in 1998. A sampling design with a density of 1 plot/ha was used, and interpolated with a perpendicular bisector. In 2002, the number of plots/ha was doubled. The influence of sample density on the mapping results was studied because it is an important decision to be made before fieldwork. Two plots/ha seem to be sufficient in order to obtain reliable information on patterns of plant species composition and vegetation types of the area, and their change over time. However, in patches where vegetation varies on a very small spatial scale this plot density was insufficient.

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, J.M. and M.A. Leibold. 2002. Spatial scale dictates the productivity-biodiversity relationship. Nature 416:427-430. Spatial scale dictates the productivity-biodiversity relationship Nature

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How are bryophyte alpha and beta diversities distributed across spatial scales along an elevational gradient in an oceanic island? Which mechanisms and drivers operate to shape them? Starting from a multiscale hierarchical sampling approach along an 1000 m elevational transect, we used additive diversity partitioning and null modeling to evaluate the contributions of the alpha and beta diversity components to overall bryophyte diversity in Terceira Island, Azores. Substrate-level diversity patterns were explored by means of the Sørensen Similarity Index and the Lloyd Index of Patchiness. Elevation-level beta diversity was decomposed into its replacement and richness differences components, with several environmental variables being evaluated as diversity predictors. Bryophyte diversity proved to be primarily due to beta diversity between elevation sites, followed by diversity among substrates. Compositional differences between neighboring sites decreased with elevation, being mainly caused by species replacement and correlating with differences in relative humidity and disturbance. At the substrate level, we found a great homogeneity in terms of species composition, coupled with a low substrate specialization rate. We conclude that, in Terceira’s native vegetation patches, regional processes, such as environmental gradients associated with elevation, play a greater role in shaping bryophyte diversity than local processes. Moister and less disturbed areas at mid-high elevation harbor a richer bryoflora, consistently more similar and stable between neighbouring sites. Simultaneously, the different substrates available are somewhat ecologically redundant, supporting few specialized species, pointing to these areas providing optimal habitat conditions for bryophytes. Our findings provide a better understanding of how bryophyte diversity is generated in Terceira Island, indicating that management and conservation measures should focus on island-level approaches, aiming to protect and rehabilitate additional natural vegetation patches at different elevations, especially in the severely disturbed lowlands.

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