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An introduction is presented in which the editor discusses topics like restoring plant ecology, nature conservation and restoration of plant communities inorder to help protect the environment.

Questions: The cover and abundance of individual plant species have been recorded on ordinal scales for millions of plots world‐wide. Ordinal cover data often need to be transformed to a quantitative form (0%–100%), especially when scrutinising summed cover of multiple species. Traditional approaches to transforming ordinal data often assume that data are symmetrically distributed. However, skewed abundance patterns are ubiquitous in plant community ecology. The questions this paper addresses are (a) how can we estimate transformation values for ordinal data that account for the underlying right‐skewed distribution of plant cover; (b) do different plant groups require different transformations; and (c) how do our transformations compare to other commonly used transformations within the context of exploring the aggregate properties of vegetation? Location: Global. Methods: We assigned Braun‐Blanquet cover‐abundance ordinal values to continuous cover observations. We fitted a Bayesian hierarchical beta regression to estimate the predicted mean (PM) cover of each of six plant growth forms within six ordinal classes. We illustrate our method using a case study (2,809 plots containing 95,812 observations), compare the model‐derived estimates to other commonly used transformations and validate our model using an independent dataset (2,227 plots containing 51,497 observations) accessed through the VegBank database. Results: Our model found that PM estimates differed by growth form and that previous methods overestimated cover, especially of smaller growth forms such as forbs and grasses. Our approach reduced the cumulative compounding of errors and was robust when validated against an independent dataset. Conclusions: By accounting for the right‐skewed distribution of cover data, our alternate approach for estimating transformation values can be extended to other ordinal scales. A more robust approach to transforming floristic data and aggregating cover estimates can strengthen ecological analyses to support biodiversity conservation and management. [ABSTRACT FROM AUTHOR]

Aims: Wetlands are key ecosystems due to their economic, social and environmental contributions. Because of their highly productive habitats and their dependence on hydro-meteorologic regimes, they are threatened worldwide by land use and climate change. In most wetlands, intensification of productive activities has been mostly accompanied by the implementation of a water management infrastructure, disrupting water and nutrient dynamics. Our aim was to analyze whether intensification of livestock raising erodes the structure and function of plant communities, as well as the quality and fertility of soils in wetlands. Location: Non-insular portion of the Lower Delta of the Paraná River, Argentina. Methods: Plant communities were characterized on the basis of their floristic composition, structural and functional diversity. Soil samples were also collected to assess soil fertility, texture and quality. Generalized mixed linear models were used to contrast these attributes across livestock management practices characterized by differing water management infrastructure (polders and channelizations) and livestock type (bovine, bubaline). Results: Remarkably fertile hydromorphic soils supported a structurally rich and functionally diverse species composition. Nevertheless, most dominant populations were terrestrial, perennial, invasive species, partially adapted to conditions of temporary flooding. Polderized livestock fields exhibited not only the lowest quality, least fertile, most compacted soils, but also lower species richness and diversity, as well as the lowest values in all non-redundant components of functional diversity. Channelized livestock fields exhibited lower species richness and taxonomic diversity as well as reduced soil quality and fertility, yet an overall increase in most non-redundant components of functional diversity. Conclusions: Promoting the loss of native flora, water management infrastructure impairs the sustainability of anthropic activities and thwarts biodiversity conservation efforts. Traditional and sustainable practices that embrace the periodicity of the flood pulse are required to preserve the taxonomic and functional diversity of plant communities, as well as the quality and fertility of soils. [ABSTRACT FROM AUTHOR]

Questions: Livestock grazing is an important disturbance in many forest ecosystems. While several studies have addressed the general impact of different grazing and light intensities on temperate forest ecosystems, little is known about how the combination of these two factors can affect the species pool and functional diversity of temperate forests. Location: Oriental beech forests of northern Iran. Methods: Vegetation and environmental data of 104 relevés were collected. These were assigned to four groups based on their light and grazing intensities. Non‐metric multidimensional scaling was used to analyze vegetation compositional relationships among groups. We used nine functional traits related to growth, reproduction, and survival for a total of 147 plant species. Redundancy analysis of community‐weighted means was used to determine the response of single traits to disturbance and environmental variables. Generalized additive models were applied to examine the shape of the response pattern of community‐weighted mean trait values across the grazing and light intensity gradients. Functional richness and functional divergence indices were used to analyze functional diversity–disturbance relationships. Results: Both light and grazing intensities significantly affected species pools, single traits, and functional divergence. Suites of trait attributes including hemicryptophytes, therophytes, grass‐like, hygromorphic leaves, insect‐pollinated, rhizomes, and runner plants were associated with high‐light sites. In closed‐canopy sites the strong filtering effect of shade resulted in suites of trait attributes including taller plants, macrophanerophytes, scleromorphic leaves, simple leaves, and berry fruits. While high‐light sites had a larger species pool, they exhibited less functional diversity. Cattle grazing can mediate the filtering effect of light and increase functional diversity in both low‐light and high‐light sites. Conclusion: Conservation measures in this region should acknowledge that moderate traditional cattle grazing combined with individual‐tree and group‐tree selection in these forests may maintain or even enhance functional diversity in these valuable ecosystems. [ABSTRACT FROM AUTHOR]

Questions: Deer‐proof fencing is an essential conservation tool to protect and recover plant species diversity in deer‐overbrowsed ecosystems, including species‐rich sub‐alpine grasslands. However, community‐level conservation tools (such as fencing) may be insufficient for single‐species conservation, particularly for non‐target endangered or rare species that are sparsely distributed. We examined whether fencing that can protect and recover total plant species richness also benefits non‐target endangered or rare species. Location: A sub‐alpine semi‐natural Kirigamine grassland in Nagano Prefecture, Japan. Methods: We conducted two complementary plant surveys (typical vegetation survey using 1‐m2 sampling units and flowering survey using 150‐m2 sampling units) to account for scarce species. We examined the community‐level responses (species richness, flowering species richness, and flowering abundance) of all species and endangered or rare species and the species‐level responses (occurrence and flowering abundance) of each species to deer fences. Results: Fencing benefited not only the community‐level response of all species, but also that of endangered or rare species. As species‐level responses, about half of 43 endangered or rare species had greater flowering abundance inside the fences than outside, but only three of them showed a positive effect on their occurrence. These results suggest that once an endangered or rare species has disappeared, it may be difficult to recover. Conclusions: Continued placement of deer fences is necessary to protect community‐level plant species richness of sub‐alpine endangered and rare species in deer‐overbrowsed ecosystems. We also highlight the necessity of additional strategies focusing on non‐target individual species across broad areas outside fences. [ABSTRACT FROM AUTHOR]

Questions: Woody encroachment affects many open habitats from semi‐deserts to wetlands and grasslands. We aimed to study the effect of native woody encroachment on grassland plant biodiversity in loess steppe fragments by analysing the vegetation composition of grasslands subjected to increasing levels of encroachment. We studied both ancient and restored grasslands with the following research hypotheses: (a) increasing woody encroachment decreases total diversity and the species richness of dry‐grassland species; and (b) the effect of woody cover on grassland biodiversity differs between ancient and restored grasslands. Location: South‐Eastern part of Transdanubia, Hungary, Central Europe. Methods: Altogether 63 loess grassland fragments were selected for the study. The percentage cover of trees, shrubs and herbaceous vegetation were recorded in 400‐m2‐sized plots (n = 110). The effects of woody encroachment and grassland age on diversity, total species richness of the herb layer, and richness of dry‐grassland species were analysed. Results: We found that woody encroachment affected the total richness of the herb layer and the species richness of dry‐grassland species. For most of the listed variables, lowest values were found for the highest woody encroachment groups. Grassland age affected the species richness of the herb layer and that of dry‐grassland species; lower values were detected in restored grasslands. In restored grasslands, Shannon diversity and species evenness were lower, while Berger–Parker dominance was higher than in ancient grasslands. Species composition and richness displayed a relatively high resistance to moderate woody encroachment; the highest decrease in diversity was detected at a high level of woody encroachment (>52% of woody cover). Conclusions: We can conclude that low to moderate woody encroachment cannot be simplistically regarded as degradation. Results suggest that moderately encroached loess grasslands can be easily restored by the suppression of woody species, as their species pool still contains many dry‐grassland species targeted for restoration. [ABSTRACT FROM AUTHOR]

Questions: In many arid and semi‐arid regions of the world, livestock husbandry is the main land use and grazing is one of the main challenges for biodiversity conservation. This also applies to the Caatinga, a unique seasonally dry tropical forest in northeastern Brazil. It is considered one of the most threatened ecosystems of Brazil. To protect semi‐arid regions from biodiversity loss, degradation, and desertification, sustainable management practices are urgently needed. However, the effect of different grazing intensities on plant diversity is not yet fully understood. In this study, we examined the effect of different grazing intensities on plant species composition, alpha and beta diversity. Location: Vicinity of the Itaparica Reservoir, northeastern Brazil. Methods: We assessed the effects of different grazing intensities (high, intermediate, no/low) on species composition, alpha and beta diversity of the tree and shrub, and the herb layer in a Caatinga area. Plant diversity of the tree and shrub layer was assessed on 45 study plots (each 20 m × 20 m), while the diversity of herbs was studied on a subset of 36 plots (four subplots, each 2 m × 2 m). Results: In total, we recorded 140 plant taxa including morphospecies. Grazing at high intensities significantly reduced almost all measures of alpha and beta diversity (tree and shrub layer) compared to areas with no or low grazing. In contrast, species composition was not significantly related to grazing but instead to altitude, which serves as an indicator of reduced anthropogenic impact such as slash‐and‐burn agriculture or tree harvesting. Conclusion: Overall, the study results show that the current livestock management has negative effects on plant diversity in Caatinga ecosystems. These results have been incorporated into guidelines provided to regional stakeholders including recommendations for adapted land‐management practices that protect and foster the biodiversity of dry forests while sustaining local livelihoods. [ABSTRACT FROM AUTHOR]

Aim To maintain biodiversity in plantation forest ecosystems it is important to understand the community assembly process. Canopy thinning effectively increases understorey diversity in plantation forests. However, the process of understorey community assembly after canopy thinning remains unclear. We compared the relative importance of two mechanisms that could affect the assembly of understorey woody communities after thinning: (1) environmental filtering due to competition from canopy trees, and (2) stochastic immigration. If the latter is dominant, the effectiveness of local treatment might be unpredictable because of the variable probability of immigration at each location. Location Yamagata Prefecture, Japan. Methods We censused the understorey tree communities in 18 quadrats (each 1 m × 1 m) in each of 49 stands of Japanese cedar plantations. The mean species richness of the 18 quadrats (alpha-diversity), variation in community composition among them (beta-diversity), deviation of beta-diversity from that of a random community (beta-deviation) and total species richness of the plots (gamma-diversity) were compared among censuses (before thinning, 2 and 5 yr after thinning). The relative contributions of two explanatory variables to the various diversities were examined: (1) basal area of canopy trees (overstorey BA, an index of environmental filtering), and (2) available seed source in the surrounding landscape (landscape effect; an index of the probability of immigration). Results Although neither beta-diversity nor gamma-diversity changed throughout the censuses, the alpha-diversity, stem abundance and beta-deviation were affected by thinning. beta-deviation increased after thinning. Overstorey BA limited alpha- and gamma-diversity throughout the censuses. The landscape effect was more significant in terms of beta-deviation after than before thinning. In addition, the effective scale of the landscape effect increased after thinning. Conclusion Our results indicate that both processes are important: thinning brought about an increase in the relative importance of stochastic immigration as well as a reduction in competitive pressure from canopy trees. These results suggest that while local treatment can increase understorey diversity, stochastic immigration from seed sources is the direct driver after thinning. Although local treatment is effective, its efficiency depends on the seed source availability in the surrounding landscape. [ABSTRACT FROM AUTHOR]

Questions Humans are altering land use and impacting grazing intensities worldwide in alpine and sub-alpine grasslands, and functional diversity ( FD) is a useful tool for predicting changes in these grassland communities and for improving biodiversity conservation. We asked: (1) how does functional richness ( FRic) differ between the five predominant grassland types in Andorra (2) of these five grassland types, which plant communities are subject to high habitat filtering and which are driven primarily by competitive interactions; (3) are certain grassland communities more prone to degradation than others; and (4) how do grazing intensity and elevation influence variations in FD indices? Locations Five types of sub-alpine and alpine grassland communities dominated by Festuca airoides, F. eskia, F. gautieri, F. paniculata and Nardus stricta in Andorra, at various elevations and with differing grazing intensities within a grassland type. Methods We used multiple functional diversity indices and structural equation modelling ( SEM) to determine how grazing intensity, elevation, species richness and productivity affect functional diversity in 222 vegetation transects. Results Both plant diversity and functional richness were higher at higher grazing intensities, with the highest values found in the F. gautieri and F. paniculata grasslands and lowest in the Nardus stricta, F. airoides and F. eskia grasslands. Habitat filtering was observed in F. airoides grasslands. There was a general tendency for higher competitive interactions among plants at higher elevations and/or when species diversity increased. None of the five grassland communities considered appears disturbed, and all present similar functional attributes between dominant species. Conclusions Our results highlight the fact that grazing is an integral part of Andorran mountain grasslands, acting as a structural component and providing higher functional richness in the most grazed communities. [ABSTRACT FROM AUTHOR]

Question Can we predict where forest regrowth caused by abandonment of agricultural activities is likely to occur? Can we assess how it may conflict with grassland diversity hotspots? Location Western Swiss Alps (400-3210 m a.s.l.). Methods We used statistical models to predict the location of land abandonment by farmers that is followed by forest regrowth in semi-natural grasslands of the Western Swiss Alps. Six modelling methods ( GAM, GBM, GLM, RF, MDA, MARS) allowing binomial distribution were tested on two successive transitions occurring between three time periods. Models were calibrated using data on land-use change occurring between 1979 and 1992 as response, and environmental, accessibility and socio-economic variables as predictors, and these were validated for their capacity to predict the changes observed from 1992 to 2004. Projected probabilities of land-use change from an ensemble forecast of the six models were combined with a model of plant species richness based on a field inventory, allowing identification of critical grassland areas for the preservation of biodiversity. Results Models calibrated over the first land-use transition period predicted the second transition with reasonable accuracy. Forest regrowth occurs where cultivation costs are high and yield potential is low, i.e. on steeper slopes and at higher elevations. Overlaying species richness with land-use change predictions, we identified priority areas for the management and conservation of biodiversity at intermediate elevations. Conclusions Combining land-use change and biodiversity projections, we propose applied management measures for targeted/identified locations to limit the loss of biodiversity that could otherwise occur through loss of open habitats. The same approach could be applied to other types of land-use changes occurring in other ecosystems. [ABSTRACT FROM AUTHOR]

Question: What are the consequences of grazing abandonment on the Stipa lessingiana dominated steppe-like grasslands? What is the relative importance of management and environmental factors in causing variation in species composition and abundance in the continuously grazed and abandoned grassland stands? Location: Transylvanian Lowland, Romania. Methods: Repeated vegetation mapping of a grassland stand, where grazing was abandoned 35 years ago; re-sampling six grassland stands surveyed 29-57 years ago. For revealing long-term changes in species composition and rank abundance PCoA ordination was applied. The relative importance of management and environmental factors in structuring vegetation were explored by CCA ordination. Diversity, evenness and the relative number and abundance of red-listed species were compared between managed and abandoned stands. Results: Our results pointed out that grasslands which were formerly grazed and dominated by S. lessingiana, in the long-term absence of grazing, have been transformed into a S. pulcherrima dominated type. Management, probably by creating bare surfaces and preventing litter accumulation, had the strongest effect on the species composition and abundance in the grasslands. Abandoned grassland stands had lower diversity and evenness compared to continuously grazed stands. While at the same time, the relative number of threatened, rare species did not differ between managed and abandoned sites. Conclusion: Maintaining extensively grazed, as well as unmanaged, Stipa dominated grasslands would be important in order to create various habitat conditions for plant species, especially threatened and rare species, and promote diversity on the landscape scale. [ABSTRACT FROM AUTHOR]