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Aims: By analysing cattle‐ and sheep‐grazed sand grasslands, we tested the following hypotheses: (i) livestock type has a stronger effect on the vegetation characteristics than grazing intensity; (ii) sheep grazing results in lower biomass and species and functional diversity than cattle grazing, regardless of intensity; and (iii) increased grazing intensity causes a shift of the trait composition in grasslands. Location: Sand grasslands in the Nyírség region, East Hungary. Methods: We selected 26 sand grassland sites grazed by cattle or sheep and classified them into four intensity levels. Vegetation composition was surveyed in 2 m × 2 m plots. We harvested the above‐ground biomass from 20 cm × 20 cm plots; then dried and sorted it to live biomass, litter, moss, and lichen. We compared Rao dissimilarity index, species richness, Shannon diversity, evenness, and the community‐weighted means of nine vegetative and generative traits along a grazing intensity gradient. We calculated functional richness, evenness, and divergence for comparison. Results: We found that some diversity metrics and community‐weighted means of most studied traits were significantly affected by grazing intensity. Several characteristics were also affected by the interaction of grazing intensity and livestock type, but none of the studied characteristics was affected by livestock type in itself. Increasing Rao dissimilarity index peaking at the fourth grazing intensity level was detected, but for other multitrait indices, no such changes were proven, except for functional divergence, which was the lowest at the first intensity level. Graminoid, forb, and litter biomass were significantly affected by intensity, but none of the biomass fractions was affected by livestock type. Conclusions: We suggest that for the management of sand grasslands, grazing intensity should be carefully adjusted, considering not only livestock units per hectare. For practical recommendations, well‐defined, long‐term experiments studying different livestock and habitat types along an intensity gradient would be essential. [ABSTRACT FROM AUTHOR]

Aims: We tested the establishment success of grassland species in the presence or absence of zoochory by livestock and identified the traits associated with successful establishment. Location: Hortobágy National Park, Hungary. Methods: In six restored species-poor grasslands we established two species-rich 4 m × 4 m source plots per site in 2013. One source plot was managed by extensive cattle grazing (“zoochory on”), the other one was fenced and protected from grazers (“zoochory off”). We monitored the vegetation development in the source plots (2014–2018), and the establishment success of sown species (2016–2018) in adjacent dispersal plots in four, 20-m-long strips per source plot in a total of 960 dispersal plots. We calculated community-weighted means of thirteen plant traits related to regeneration and competitive ability. The effect of grazing, year, distance from source plots, grazing–year and grazing–distance interactions on population and trait dynamics in the source and dispersal plots were analysed with generalized linear mixed-effect models. Results: Although grazing reduced the cover and flowering success of sown species in the source plots, the number of successful establishment events was higher in dispersal plots next to grazed source plots. The sown species were the most abundant in plots adjacent to source plots, but occurred at all monitored distances. Zoochory favoured perennial plants with high specific leaf area (SLA), low leaf dry matter content (LDMC), short stature, light seeds, early flowering period, high clonal index and anemochory index. Conclusions: We showed that species that can colonize the matrix with and without zoochory have contrasting trait syndromes. In grazing-adapted ecosystems, fencing source populations of target species does not always seem to be a good option. It was a good tool for increasing the cover and flowering success of the sown species in the short run, but it significantly decreased their chance to colonize the surrounding area in the long run. [ABSTRACT FROM AUTHOR]

Sowing of grass seed mixtures is a feasible and cost‐effective method for landscape‐scale grassland restoration. However, sowing only grasses usually leads to species‐poor and dense swards, where the establishment of target forbs is hampered by microsite and propagule limitation. To overcome these limitations and increase the diversity of species‐poor sown grasslands, we developed a novel method by creating "establishment gaps.". We used tillage to open gaps of 1‐, 4‐, and 16‐m2 size in the dense grass sward of six species‐poor restored grasslands in the Great Hungarian Plain. We sowed high‐diversity seed mixtures of 35 native species into all gaps. We analyzed vegetation development during the first 5 years after setting up the trial. We also studied the colonization dynamics of the sown species along four 20‐m transects around each gap, resulting in a total of 1440 plots of 1‐m2 size that were studied. Our results indicated that most of the sown species were able to establish permanently in the gaps. The total cover and the cover of perennial sown species increased and the cover of short‐lived sown species decreased independent of gap size. There was only a moderate level of weed abundance in the gaps, and weed cover decreased over the years. The sown target species started to colonize the species‐poor grasslands surrounding the gaps within 5 years. The highest number of species and individuals dispersed from the 4‐m2 gaps, as they had a more stable development than smaller gaps and were exposed to lower grazing pressure than large ones. [ABSTRACT FROM AUTHOR]

In the Palaearctic steppe zone, overgrazing was identified as one of the key drivers of declining grassland biodiversity, which underlines the necessity of the functional evaluation of increased grazing pressure on grassland vegetation. We tested the following hypotheses: (a) The effect of grazing intensity on species and functional diversity is strongly dependent on grassland type. (b) The magnitude of diet selectivity of grazers decreases with increasing grazing intensity. (c) Increasing grazing intensity increases evenness and functional evenness of the subjected grasslands. We analyzed vegetation patterns in four types of grasslands (Dry alkali short‐grass steppes, Dry loess steppes, Non‐alkali wet and Alkali wet grasslands) along an intensity gradient of beef cattle grazing at 73 sites in Hungary. Species richness, Shannon diversity, evenness, and four leaf traits were analyzed. We calculated community‐weighted means for each single trait, and multi‐trait functional richness, functional evenness, and divergence for all leaf traits. All species and functional diversity metrics were significantly affected by the grassland type, except leaf dry matter content. The effect of interaction between grazing intensity and grassland type was also significant for functional richness, functional evenness, community‐weighted means of leaf area, and for species richness and evenness. An upward trend of specific leaf area was detected in all grasslands with the highest scores for the overgrazed sites, but the change was also grassland type dependent. The detected trend suggests that with increased intensity the overall selectivity of grazing decreased. We found that evenness was affected but functional evenness was not affected by grazing intensity. Functional evenness scores were more related to the grassland type than to changes in grazing intensity, and displayed a high variability. We stress that one‐size‐fits‐all strategies cannot be recommended and actions should be fine‐tuned at least at the level of grassland type. Our results clearly indicated that the effects of grazing intensity are strongly grassland type dependent. This implies that management strategies and decisions should be fine‐tuned at least at the level of grassland type. [ABSTRACT FROM AUTHOR]