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In the Eurasian forest-steppe, with increasing aridity, the balance between naturally co-existing forest and grassland patches is expected to shift towards grassland dominance in the long run, although feedback mechanisms and changes in land-use may alter this process. In this study, we compared old and recent aerial photographs of Hungarian forest-steppes to find out whether and how the forest proportion and the number of forest patches change at the decadal time scale. The percentage area covered by forest significantly increased in all study sites. The observed forest encroachment may be a legacy from earlier land-use: due to ceased or reduced grazing pressure, forests are invading grasslands until the potential forest cover allowed by climate and soil is reached. The number of forest patches significantly increased at one site (Fülöpháza), while it decreased at two sites (Bugac and Orgovány) and showed no significant change at the fourth site (Tázlár). This indicates that forest encroachment can happen at least in two different ways: through the emergence of new forest patches in the grassland, and through the extension and coalescence of already existing forest patches. Though the present work revealed increasing tree cover at a decadal time scale, the dynamic process should be monitored in the future to see how the vegetation reacts to further aridification. This could help devise a conservation strategy, as the woody/non-woody balance has a profound influence on basic ecosystem properties. [ABSTRACT FROM AUTHOR]

We selected 15 sheep‐grazed sand pastures along a gradient of increasing grazing intensity to study the fine‐scale patterns of main biomass fractions (green biomass, litter) and that of plant species and functional groups (life forms and social behaviour types). We classified them into five grazing intensity levels based on stocking density, proximity to drinking and resting places and the number of faeces. We aimed to answer the following questions: (i) How does increasing intensity of sheep grazing affect the amount of green biomass, the species richness and their relationship in sand pastures? (ii) How does increasing intensity of sheep grazing affect the biomass of perennial and short‐lived graminoids and forbs? (iii) How does the disturbance value—expressed in the biomass ratio of disturbance‐tolerant and ruderal species—change along the gradient of grazing intensity? A unimodal relationship between green biomass and species richness was detected; however, the ordination (canonical correspondence analysis, CCA) showed no clustering of pastures subjected to the same levels of grazing intensity. Along the grazing intensity gradient we found an increasing trend in species richness and significant differences in green biomass (decreasing trend), litter (decreasing trend), graminoids (decreasing trend) and short‐lived forbs (increasing trend). We found an increasing amount of disturbance‐tolerant and ruderal species with increasing grazing intensity. We suggest that we might need to use multiple scales for sampling and a fine‐scale assessment of grazing intensity. Our findings might be instructive for pastures in densely populated regions, which are prone to the encroachment of disturbance‐tolerant and ruderal species. [ABSTRACT FROM AUTHOR]

Repeated surveys of vegetation plots offer a viable tool to detect fine‐scale responses of vegetation to environmental changes. In this study, our aim was to explore how the species composition and species richness of dry grasslands changed over a period of 17 years, how these changes relate to environmental changes and how the presence of spring ephemerals, which may react to short‐term weather fluctuations rather than long‐term climatic trends, may influence the results. A total of 95 plots was surveyed in 2005 and resurveyed in 2022 in dry grasslands of the Kiskunság Sand Ridge (Hungary, Eastern Central Europe), where there has been a significant increase in mean annual temperature during the last decades, while no trends in precipitation can be identified. Db‐RDA was performed to reveal compositional changes. The changes in environmental conditions and naturalness state were assessed using ecological and naturalness indicator values. We also compared per‐plot richness of all species, native species and non‐native species of the old and the new relevés. All analyses were repeated after removing all spring ephemerals. We found clear temporal changes in species composition. Mean temperature indicator values increased, while mean soil moisture indicator values decreased during the 17 years. Also, decreasing per‐plot richness was detected both for all species and for native species, while mean naturalness increased. After the removal of spring ephemerals, the compositional changes were less obvious although still significant. The increase in the temperature indicator values remained significant even without the spring ephemerals. However, the decrease in the moisture indicator values, the decrease in the number of all species and native species, as well as the increase in naturalness indicator values disappeared when spring ephemerals were excluded from the analyses. Our study demonstrates that between‐year weather differences and long‐term environmental trends both contribute to observed vegetation changes. [ABSTRACT FROM AUTHOR]

Global warming, elevated atmospheric CO2 concentrations and increased likeliness of extreme drought and wildfires in many regions will likely favour C4 grass species. To support future management actions, we explored the effect of the encroachment of an invasive perennial C4 grass, Sporobolus cryptandrus on the composition of soil seed banks in dry sand grasslands in Central Europe. In five mass‐locality sites of the species we assessed the composition and vertical segmentation of the soil seed bank in 12 1‐m2 plots along an increasing cover of the invasive species. We found that the seed bank diversity and density decreased with increasing sampling depth; the decrease in density was affected by the increasing S. cryptandrus cover. Neither the diversity nor the seed bank density of other species were affected by increasing S. cryptandrus cover but both were affected by the sampling site. Most of the studied seed bank characteristics were affected by the sampling depth, but none of them were affected by the increasing cover of S. cryptandrus. Increasing cover of S. cryptandrus in the vegetation was associated with an increasing proportion of S. cryptandrus seeds in the seed bank, and we found a low‐density soil seed bank of the species even in plots with no S. cryptandrus cover. Our finding that S. cryptandrus forms a massive soil seed bank, together with the predicted decrease in the precipitation of the summer months and increase in the frequency of droughts in the region, projects further rapid spread of the species. [ABSTRACT FROM AUTHOR]

In many regions, wild large herbivores have maintained open landscapes up to and including historic times, but, more recently, have been largely replaced by domestic livestock. By employing extensive and traditional grazing and browsing regimes, conservation actions support biodiversity and recovery in natural and degraded areas. However, grazing also plays other important ecological roles, for example, in the maintenance and/or recovery of important ecosystem services, such as biomass production and carbon sequestration. Understanding herbivore effects on plant composition and functional diversity, and ecosystem functioning and services, is essential for informing ecological theory and practice. The current Special Issue highlights that the effects of grazing on vegetation are strongly context‐dependent. The articles identify at least three major factors acting in concert, which are responsible for contrasting diversity and functional patterns of vegetation subjected to herbivores: (i) herbivore identity; (ii) grazing intensity; and (iii) vegetation type. Insights from this Special Issue imply that long‐term experiments across different habitat types and in underrepresented regions are needed to provide valuable information for grazing planning and management. They also demonstrate that integrating indigenous and traditional ecological knowledge, and considering socio‐economic contexts, can provide opportunities for improving sustainable grazing management. [ABSTRACT FROM AUTHOR]