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Background: Burrowing mammals are important ecosystem engineers, especially in open ecosystems where they create patches that differ from the surrounding matrix in their structure or ecosystem functions. Methods: We evaluated the fine-scale effects of a subterranean ecosystem engineer, the Lesser blind mole rat on the vegetation composition of sandy dry grasslands in Hungary. In this model system we tested whether the characteristics of the patch (mound size) and the matrix (total vegetation cover in the undisturbed grassland) influence the structural and functional contrasts between the mounds and the undisturbed grasslands. We sampled the vegetation of 80 mounds and 80 undisturbed grassland plots in four sites, where we recorded the total vegetation cover, and the occurrence and cover of each vascular plant species. We used two proxies to characterise the patches (mounds) and the matrix (undisturbed grassland): we measured the perimeter of the mounds and estimated the total vegetation cover of the undisturbed grasslands. First, we compared the vegetation characteristics of the mounds and the surrounding grasslands with general linear models. Second, we characterised the contrasts between the mounds and the undisturbed grassland by relative response indices (RRIs) of the vegetation characteristics studied in the first step. Results: Species composition of the vegetation of the mounds and undisturbed grasslands was well separated in three out of the four study sites. Mounds were characterised by lower vegetation cover, lower cover of perennial graminoids, and higher diversity, and evenness compared to undisturbed grasslands. The contrast in vegetation cover between mounds and undisturbed grasslands increased with decreasing patch size. Increasing vegetation cover in the matrix grasslands increased the contrasts between the mounds and undisturbed grasslands in terms of total cover, perennial graminoid cover, diversity, and evenness. Our results suggest that mole rat mounds provide improved establishment conditions for subordinate species, because they are larger than other types of natural gaps and are characterised by less intense belowground competition. The ecosystem engineering effect, i.e., the contrast between the patches and the matrix was the largest in the more closed grasslands. [ABSTRACT FROM AUTHOR]

Aim: We evaluated stands of the invasive grass, Sporobolus cryptandrus in its native North American range and its non-native European range, where it is a recent invader. Our aim was to reveal how the species’ increasing abundance affects functional diversity and the ecosystem service-provisioning capacities of plant communities in both ranges. Location: Sand grasslands in the Kiskunság, Hungary and in Montana, USA. Methods: All vascular plant species and their relative abundances were recorded in a stratified random manner in 1 m × 1 m plots in each range, using the following cover categories of Sporobolus as strata: 1%–25%, 26%–50%, 50%–75%, and 75%–100%. The functional characteristics of the plant communities in the two continents were compared. We performed comparisons of the communities both with and without including Sporobolus. Results: Increasing Sporobolus cover resulted in a lower functional diversity and species richness, reduced average specific leaf area and increased the height of whole plant communities in both ranges but these effects were significantly stronger in the non-native stands. Sporobolus also negatively affected the cover of insect-pollinated plant species and the proportion of native perennials, switching the rest of the community from perennial-dominated to annual-dominated. In plant communities without Sporobolus, increasing Sporobolus cover led to a higher specific leaf area and seed mass in both ranges, but average height was decreasing along the Sporobolus abundance gradient in the native range, whereas it was increasing in the non-native range. Conclusions: The spread of Sporobolus, away from its native range, leads to the impoverishment of host communities and compromises the biomass and floral resourceprovisioning capacity of the vegetation to higher trophic levels. Tackling the spread of this new invader should therefore be a priority task. [ABSTRACT FROM AUTHOR]

In general, database data are a good substitution for time- and resource-consuming trait measurements; however, there is low spatial coverage for a large number of taxa (Kattge et al. [12]), and there is a severe lack of data for endemic, locally rare or red-listed species. In this paper we provide original leaf trait data of vascular plant species from the Pannonian ecoregion. Our data are well compatible with other local trait datasets (Török et al. [44], [45]; Lhotsky et al. [24]) and herbaria (Molnár et al. [31]; Takács et al. [41]; E-Vojtkó et al. [5]; Takács et al. [42]; Nótári et al. [33]) from the Pannonian ecoregion and can be amalgamated in a large plant trait and life history database in the future. [Extracted from the article]

Plant species performance in rangelands highly depends on the effect of grazing and also on the occurrence of unpalatable benefactor species that can act as biotic refuges protecting neighboring plants from herbivores. The balance between facilitation and competition may changes with the benefactor density. Despite the high number of studies on the role of biotic refuges, the density dependent effects of unpalatable herbaceous plants on the performance of other species, and on the habitat heterogeneity of rangelands are still unclear. Therefore, we performed a study to test the following hypotheses: (i) Performances of understory species follow a humped-back relationship along the density gradient of the unpalatable benefactor species. (ii) Small-scale heterogeneity of the vegetation decreases with increasing benefactor density. We studied meadow steppes with medium intensity cattle grazing in Hungary. We surveyed understory species' performance (number of flowering shoots and cover scores) along the density gradient of a common, native unpalatable species (Althaea officinalis). Our findings supported both hypotheses. We found unimodal relationship between the benefactor cover and both the flowering success and richness of understory species. Moreover, small-scale heterogeneity declined with increasing benefactor cover. In this study we detected a humped-back pattern of facilitation along the density gradient of an herbaceous benefactor in pastures. Indeed, this pattern was predictable based on such conceptual models like "consumer pressure-abiotic stress model," "humped-back model," "intermediate disturbance hypothesis," and "disturbance heterogeneity model"; but until now the validity of these relationships has not been demonstrated for herbaceous species. By the demonstration of this effect between herbaceous species we can better forecast the responses of grasslands to changes in management. [ABSTRACT FROM AUTHOR]

Question: Spontaneous succession is the most natural and cost‐effective solution for grassland restoration. However, little is known about the time required for the recovery of grassland functionality, i.e., for the recovery of reproductive and vegetative processes typical of pristine grasslands. Since these processes operate at different scales, we addressed the question: do reproductive and vegetative processes require different recovery times during spontaneous succession? Location: Kiskunság sand region (Central Hungary). Methods: As combinations of plant traits can be used to highlight general patterns in ecological processes, we compared reproductive (pollination‐ and dispersal‐related) and vegetative (growth form) traits between recovered grasslands of different age (<10 years old; 10–20 years old; 20–40 years old) and pristine grasslands. Results: During spontaneous succession, the reproductive trait spectra became similar to those of pristine grasslands earlier than the vegetative ones. In arable land abandoned for 10 years, pollination‐ and dispersal‐related trait spectra did not show significant difference to those of pristine grasslands; anemophily and anemochory were the prevailing strategies. Contrarily, significant differences in the growth form spectrum could be observed even after 40 years of abandonment; in recovered grasslands erect leafy species prevailed, while the fraction of dwarf shrubs and tussock‐forming species was significantly lower than in pristine grasslands. Conclusions: The recovery of the ecological processes of pristine grasslands might require different amounts of time, depending on the spatial scale at which they operate. The reproductive trait spectra recovered earlier than the vegetative one, since reproductive attributes first determine plant species sorting at the regional level towards their respective habitats. The recovery of the vegetative trait spectrum needs more time as vegetative‐based interactions operate on a smaller spatial scale. Thus, vegetative traits might be more effective in the long‐term assessment of restoration success than the reproductive ones. [ABSTRACT FROM AUTHOR]

Context: Landscape and habitat filters are major drivers of biodiversity of small habitat islands by influencing dispersal and extinction events in plant metapopulations.Objectives: We assessed the effects of landscape and habitat filters on the species richness, abundance and trait composition of grassland specialist and generalist plants in small habitat islands. We studied traits related to functional spatial connectivity (dispersal ability by wind and animals) and temporal connectivity (clonality and seed bank persistence) using model selection.Methods: We sampled herbaceous plants, landscape (local and regional isolation) and habitat filters (inclination, woody encroachment and disturbance) in 82 grassland islands in Hungary.Results: Isolation decreased the abundance of good disperser specialist plants due to the lack of directional vectors transferring seeds between suitable habitat patches. Clonality was an effective strategy, but persistent seed bank did not support the survival of specialist plants in isolated habitats. Generalist plants were unaffected by landscape filters due to their wide habitat breadth and high propagule availability. Clonal specialist plants could cope with increasing woody encroachment due to their high resistance against environmental changes; however, they could not cope with intensive disturbance. Steep slopes providing environmental heterogeneity had an overall positive effect on species richness.Conclusions: Specialist plants were influenced by the interplay of landscape filters influencing their abundance and habitat filters affecting species richness. Landscape filtering by isolation influenced the abundance of specialist plants by regulating seed dispersal. Habitat filters sorted species that could establish and persist at a site by influencing microsite availability and quality. [ABSTRACT FROM AUTHOR]

There is a conflict between nature conservation and thatching industry regarding the management of reedbeds. On one hand, reedbeds are of an economical importance by providing thatching material, on the other hand, they harbour several endangered species. Reedbeds are typically managed by winter cutting, but its impacts on biodiversity are poorly understood. Our aim was to study the effects of winter cutting on the habitat diversity and structural heterogeneity of wetlands in a lowland alkali landscape (East-Hungary). We tested the following hypotheses: (i) Both diversity of plant species and habitat diversity are lower in winter cut wetlands compared to unmanaged stands. (ii) The distribution of biomass (green biomass, litter and standing dead biomass) is more homogeneous in winter cut wetlands compared to unmanaged ones. We found that winter cutting decreased habitat diversity and structural heterogeneity at multiple scales. Number of plant species and all measures of habitat diversity (number of patches, vegetation types and the length of vegetation margins) had lower scores in cut wetlands than in unmanaged ones. We found that unmanaged wetlands harboured high amount of accumulated biomass and they also maintained high habitat diversity likely due to the heterogeneous distribution of the biomass. In unmanaged wetlands, biomass accumulation did not decrease habitat diversity and also contributed to a higher structural heterogeneity. In cut wetlands, expansion of reed was an important driver of the decrease in habitat diversity and structural heterogeneity. Reed expansion likely overrode fine-scale edaphic conditions (hydrology and salinity) in shaping vegetation patterns; thus we suggest to avoid intensive winter cutting. [ABSTRACT FROM AUTHOR]

Grasslands recovered by sowing low diversity seed mixtures of local provenance are usually managed by mowing. Besides restoration success only a few studies have focused on the direct effects of post-restoration mowing on recovered grassland vegetation. In this study we followed vegetation changes in 13 successfully recovered grasslands in 5 × 5-m-sized sites with continuous and ceased mowing at Hortobágy National Park, East-Hungary. We asked the following questions: (i) What are the effects of cessation of mowing on the vegetation structure and diversity of recovered grasslands? (ii) What are the effects of cessation of mowing on the abundance of sown grasses, target and undesirable species? (iii) Is yearly mowing an appropriate management tool for the maintenance of recovered grasslands? Our results showed that the cessation of mowing caused litter accumulation, while diversity, total vegetation cover and the cover of sown grasses decreased compared to the mown sites. The cover of undesirable perennial species was significantly higher in unmown sites than in mown ones. The species composition of mown sites remained more similar to near-natural grasslands than the unmown ones. Our results suggest that without regular post-restoration mowing the favourable status of recovered grasslands can rapidly decline due to litter accumulation and by the expansion of undesirable species, even in the short-run. We also stress that while yearly mowing is enough to maintain grasslands recovered by low-diversity seed sowing, it cannot be considered to be enough to recover target vegetation composition. [ABSTRACT FROM AUTHOR]

Recruitment by seeds is essential both in vegetation dynamics and in supporting biodiversity in grasslands. The recruitment by seeds is feasible in suitable vegetation gaps from the seed rain and/or by establishment from persistent soil seed banks. Cessation of grassland management results in litter accumulation, which leads to the decline of species diversity by the decreased availability of open patches. Low amounts of litter is often beneficial, while high amounts of litter is detrimental for seed germination and seedling establishment of short-lived species. In a designed indoor experiment, we explored the effect of litter on seedling establishment by germinating six short-lived Brassicaceae species with both increasing seed mass and litter cover. We found that both seed mass and litter had significant effect on germination and establishment of the sown species. Small-seeded species were significantly negatively affected by the 300 and/or 600 g/m litter layers. No negative litter effect was detected for species with high seed masses ( Lepidium spp.). No overall significant positive litter effect was found, although for most of the species cumulative seedling numbers were not the highest at the bare soil pots. Our results suggest that the negative effects of litter are less feasible on the large-seeded short-lived species than on that of small-seeded ones. [ABSTRACT FROM AUTHOR]

Abstract: Grassland restoration on former croplands offers good opportunity to mitigate the loss of grassland biodiversity. Weed suppression can be another benefit, which becomes increasingly important because of the high recent rate of abandonment of arable lands in Central and Eastern Europe. Our aim was to evaluate the usefulness of sowing two low-diversity seed mixtures followed by annual mowing, a frequently used restoration technique, in weed suppression. We found that rapidly forming cover of sown grasses effectively suppressed short-lived weeds and their germination except in the first year. The detected dense seed bank of short-lived weeds points out the possibility and threat of later weed infestation. In the short run perennial weeds cannot be suppressed easily by sowing and annual mowing. We found that the effectiveness of seed sowing followed by mowing in weed suppression can be different on sites with different history or seed mixture. Rapidly establishing perennial weeds, such as Agropyron species were only detected in former alfalfa fields; Cirsium arvense was found in former cereal and sunflower fields but not in former alfalfa fields. We found that the rate of weed suppression and success was influenced by the seed mixtures used. In several alkali restorations the high proportion of perennial weeds was detected in year 3. In loess restorations, much lower scores were typical. This was likely caused by the different seed mixture used. The loess seed mixture contained seeds of a clonally spreading tall-grass, Bromus inermis, which could compete more effectively with clonally spreading weeds, than could short grass species with or without tussock forming. Our findings indicate that post-restoration management require carefully designed actions that are fine-tuned addressing specific threats at the site level. [Copyright &y& Elsevier]

Free grazing and herding of local breeds have a long tradition in management and conservation of extended grassland habitats such as alkali steppes. However, there is a lack in studies evaluating the effects of grazing types and regimes on the vegetation composition and functional diversity. We selected Artemisia steppes, a widespread type of alkali steppes, to study the changes of vegetation composition and diversity along a grazing intensity gradient. We recorded the cover of vascular plant species, in altogether 150, 2 × 2-m-sized plots of 15 steppes in 2014. The steppes were managed by free grazing, traditional Hungarian Grey cattle grazing (low, moderate and high intensity), or by heavy grazing (Grey cattle and sheep, and additional donkey grazing). We answered the following questions: (i) How do the species richness, diversity and species evenness change along the increasing intensity of grazing? (ii) How does the grazing affect the functional trait composition along the intensity gradient? (iii) How similar is the composition and diversity of free grazed steppes to the pastoral grazed ones? We detected no significant differences in species richness but a humped-back curve with a peak at the medium grazing intensity was found for the Shannon diversity, evenness and the proportion of subordinated target species. The highest Rao’s quadratic entropy was found for low intensity grazing. The lowest scores of multi-trait functional evenness were detected for the medium grazing intensity, while for multi-trait functional divergence both medium and very high intensity displayed low scores. The intensity of grazing was negatively correlated with the plant height and LDMC, while positively with the rosette forming, SLA, thousand-seed weights, terminal velocity and flowering period. Our results suggest that for the highest functional diversity a low intensity traditional cattle grazing is recommended. A medium grazing intensity should be chosen to have the highest proportion of subordinated target species of conservation interest, and the highest species diversity and evenness. Our findings suggest that free grazing and low-intensity traditional grazing can be substitutive to each other; various grazing intensities from low to medium, alternating in space and/or time can be appropriate to maintain high compositional diversity. [ABSTRACT FROM AUTHOR]

Abstract: Technical reclamation of grasslands is a powerful tool for conserving biodiversity in fragmented landscapes. Plant material transfer and sowing seeds of local provenance are used most frequently to recover grassland vegetation in former croplands. The joint application of these methods is rarely used, although it has the potential to gain a predictable and directed vegetation development with effective early weed suppression. We studied the effectiveness of combining low diversity seed sowing and hay-transfer in weed suppression and recovery of perennial grassland vegetation in Hortobágy Puszta, Central-Europe, by testing the following hypotheses: (i) lower weed cover and biomass is expected in vegetation recovered by the joint method of sowing and hay transfer than by seed sowing only. (ii) With sowing and additional hay transfer a higher rate of establishment of Festuca species is expected than with sowing only. Our results supported both hypotheses. We found that the additional application of hay significantly accelerated the development of perennial grassland vegetation and provided a higher weed suppression rate in the first year and onwards in most plots than seed sowing only. A higher establishment rate was detected both in the cover and the biomass of perennial grasses including Festuca species in all plots with hay addition than with sowing only. Our results suggest that a combination of hay transfer and low diversity sowing may provide a cost-effective alternative to the more costly high-density sowing and if proper sources for high-diversity hay are available, it may replace high-diversity seed mixtures. [Copyright &y& Elsevier]