Abbreviations acT0 = average accumulated temperatures above 0°C; cvP = coefficient of inter-annual variation of precipitation; P = mean annual precipitation; SOC = soil organic carbon; srad = mean annual shortwave radiation. Nomenclature eFloras (2008)Abstract Questions: Livestock grazing and abiotic environmental factors both shape grassland systems; however, the relative importance of their impacts on plant species composition and soil fertility has rarely been investigated. Focusing on Tibetan grasslands, which are of global ecological importance and exhibit broad climatic and elevational gradients, we asked whether grazing effects are pronounced in humid regions, while climate controls are overriding grazing effects in semi-arid regions.Location: Twenty-eight sites across Tibetan pastures, China; 2820-5150 m a.s.l.Methods: We used multivariate analyses and generalized linear mixed models to examine the effects of livestock activity (hotspots with excessive trampling and nutrient input, heavy, moderate and light grazing), habitat (meadow, steppe, steppe-meadow) and their interactions. We focused on plant species composition, richness and concentrations of soil organic carbon (SOC), total N and other plant-available nutrients in soils. Major environmental factors were precipitation, temperature and elevation. Plant indicator species sensitive to trampling and/or grazing were identified.Results: Livestock grazing changed plant species composition and overall soil fertility across habitats. However, effects were only pronounced in hotspots directly adjacent to herder camps, while differences between grazing intensity levels were weak. Heavy grazing favoured annual species, reduced concentrations of SOC and total N in meadows. The environmental factors that control plant communities and soil condition varied among habitats. Plants and soils were more tightly linked in steppes and steppe-meadows than in meadows.Conclusions: Several plant species were identified as frequently and reliably present in hotspots of livestock activity, thus are indicative of intensive trampling and excess plant available nutrient inputs. Overall, plant species composition and soil condition across Tibetan pastures were weakly affected by intensified grazing alone compared to that shaped by environmental factors. This clearly refutes the broadly held perception that increased grazing intensity leads to grassland degradation. Such differing and strong abiotic impacts should be considered in future grassland management and conservation.

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Questions: (a) In which ways do woody species encroachment and fire affect vegetation and seed bank composition, structure and diversity in Transylvanian dry grassland; (b) do native and non-native woody species differ with respect to their impact on grassland community composition and structure; (c) is burning useful to control woody species encroachment; and (d) can soil seed banks contribute to the restoration of grasslands in Transylvania? Location: Transylvania, Romania. Methods: We collected data on vegetation and seed bank composition in 4 m 2 plots in 16 shrub-encroached grasslands and adjacent open grassland. Data were analyzed with regard to the impact of woody species encroachment (native vs non-native) and fire on grassland vegetation and the seed bank using NMDS and LME models combined with ANOVA and Tukey contrast tests.Results: Encroachment was accompanied by a decrease in plant species diversity and altered microclimatic conditions. There was a lack of sufficient evidence for a difference in effect size between native and non-native woody species on tested vegetation or seed bank parameters. While the effects of fire on vegetation were weak compared to encroachment, burning failed to reduce the cover of woody species sustainably. Grassland vegetation and the seed bank differed significantly in species composition and diversity, indicating a limited potential for restoration from the seed bank alone. Conclusions:To halt secondary succession in Transylvanian grassland sustainably, we suggest the establishment of a post-fire management regime including the cutting of woody species and/or re-introduction of grazing and mowing. Grassland restoration from the seed bank may be supported by the introduction of species from surrounding intact grassland. K E Y W O R D S dry grassland, fire, Hippophae rhamnoides, invasive shrub, native and non-native woody species, plant species composition, plant species diversity, restoration and management, seed bank, Transylvania, vegetation, woody species encroachment 410 | Applied Vegetation Science GÖRZEN Et al.

Plant phenology, i. e. the timing of life cycle events, is related to individual fitness and species distribution ranges. Temperature is one of the most important drivers of plant phenology together with day length. The adaptation of their phenology may be important for the success of invasive plant species. The present study aims at understanding how the performance and the phenology of the invasive legume Lupinus polyphyllus vary with latitude. We sampled data across a >2000 km latitudinal gradient from Central to Northern Europe. We quantified variation in phenology of flowering and fruiting of L. polyphyllus using >1600 digital photos of inflorescences from 220 individual plants observed weekly at 22 sites. The day of the year at which different phenological phases were reached, increased 1.3–1.8 days per degree latitude, whereas the growing degree days (gdd) required for these phenological phases decreased 5–16 gdd per degree latitude. However, this difference disappeared, when the day length of each day included in the calculation of gdd was considered. The day of the year of the earliest and the latest climatic zone to reach any of the three studied phenological phases differed by 23–30 days and temperature requirements to reach these stages differed between 62 and 236 gdd. Probably, the invasion of this species will further increase in the northern part of Europe over the next decades due to climate warming. For invasive species control, our results suggest that in countries with a large latitudinal extent, the mowing date should shift by ca. one week per 500 km at sites with similar elevations.

Intensive agriculture is among the main drivers of diversity decline worldwide. In Central Europe, pressures related with agriculture include habitat loss due to the consolidation of farming units, pesticide and fertilizer use, and shortened crop rotations. In recent decades, this development has resulted in a severe decline of agrestal plant communities. Organic farming has been suggested as a biodiversity friendly way of farming, as it strongly restricts the use of synthetic pesticides and fertilizers and relies on longer crop rotations. It may thus help in saving agrestal plant communities in the future. In this study, we assessed the long-term effects of three types of arable field management (conventional farming, organic farming, and bio-dynamic farming) on three farms in the federal state of Schleswig-Holstein, Northern Germany. We collected data on above-ground plant communities and seed banks and analyzed them with regards to the impact of the farming system and their position in the field using nonmetric multi-dimensional scaling (NMDS) and linear mixed effects models (LME) combined with ANOVA and Tukey contrast tests. Plants in organically or bio-dynamically managed fields differed in their composition and traits from those occurring in conventionally managed fields, i.e., they showed a preference for higher temperatures and were dominated by insect-pollinated species. While conventional farming had negative effects on vegetation and the seed bank, organic and bio-dynamic farms had neutral or slightly positive effects on both. This highlights the potential of the latter two to conserve species even in an intensively managed landscape. In addition, this may halt or even reverse the decrease in arthropod, bird, and mammal species, since agrestal plants constitute an important component of food-webs in agricultural landscapes.