Explore the vast range of titles available.

Aims: We investigated urban grasslands to: (1) explore current patterns of plant species richness in high-maintenance vs low-maintenance grasslands, (2) investigate environmental drivers of plant species richness and composition, and (3) derive management recommendations and assess the potential for plant species introduction. Location: Cities of Cologne (50°56' N, 6°57' E) and Münster (51°57' N, 7°37' E), North Rhine-Westphalia, Germany. Methods: We performed plant inventories and measured soil and above-ground biomass characteristics in 100 urban grasslands in two cities differing in population size and environmental setting. The data set covered 35 high-maintenance grasslands, which are cut or mulched up to 14 times a year, and 65 lowmaintenance grasslands with one to two cuts per year or sheep grazing. We used ANCOVA and DCA to assess drivers of vegetation composition and species richness. The floristic potential and options to restore biodiversity were assessed taking into account maintenance intensity and key abiotic variables of the grasslands using thresholds derived from published literature and our own data. Results: High-maintenance urban grasslands harboured significantly lower plant species richness compared to low-maintenance grasslands. However, plant species richness of both grassland types turned out to be lower than that of comparable semi-natural agricultural grasslands. Floristic composition was primarily conditioned by maintenance intensity, but for plant species richness environmental factors such as soil pH, phosphorus availability and city were additionally important. Just eight of the 100 studied urban grasslands were found to be already valuable and species-rich, whereas the vast majority showed relatively low species richness but a high potential for species introduction. Conclusions: Apparently, most urban grasslands exhibited quite constrained plant species richness, suffering from high-maintenance intensity but probably also from dispersal and seed limitations. Nevertheless, as the majority of the studied grasslands showed favourable abiotic preconditions for higher plant species richness, restoration techniques using species introduction could be an easy and promising method to support grassland biodiversity in urban areas.

Aim Grazing intensity and fire patterns across the Eurasian steppes have changed dramatically over the past decades due to the collapse of the Soviet Union in 1991, and Kazakhstan is now a global fire hotspot. The implications of these changes for ecosystem functioning are largely unclear. We aimed to understand the effects of changed grazing intensity and fire frequency on a key ecosystem engineer, the yellow ground squirrel Spermophilus fulvus, on a very large scale. Location Kazakhstan. Methods Ground squirrels were surveyed in an area of ca. 100,000 ha in the dry steppe of central Kazakhstan, using hierarchical distance sampling at more than 200 random points, stratified by fire frequency and livestock grazing intensity. We modelled abundance as a function of different variables, grouped at the landscape scale (fire and grazing), meso‐scale (soil and vegetation structure) and at burrow scale (plant traits such as palatability, digestibility and nutrient content). Results Ground squirrels prefer areas of a high wormwood cover (Artemisia spp.) and high plant species richness, which are moderately grazed, preferably by cattle, with only rare fire occurrence. High squirrel densities were also related to the availability of nitrogen‐rich plants of high nutritional value for herbivores. Main Conclusions Yellow ground squirrels seem to reach their density optima by balancing trade‐offs between optimal foraging in areas of short, nutrient‐rich vegetation and a good visibility of approaching predators. Post‐Soviet changes in grazing pressure, resulting in higher fire recurrence rates due to grass encroachment and litter accumulation (i.e. fuel for wildfire), have likely affected the abundance of burrowing mammals and associated biodiversity across huge parts of the Eurasian steppes and semideserts.

Questions: (1) How does functional composition and diversity respond to different timings and frequencies of mowing or fallow treatment; (2) to which species assembly and related ecosystem processes do these developments correspond; and (3) what is the time course of these developments, and do they reach a stable state? Location: North-western Germany. Methods: In 1987, a field experiment in nine wet meadow sites formerly exploited as fertilized meadows or pastures was established with four management treatments: (1) mowing twice a year in June/July and in September, (2) mowing once a year in June/July, (3) mowing once a year in September, and (4) leaving fallow except for shrub removal. Vegetation was recorded at least every second year and the functional composition (CWM) and diversity (Rao's quadratic entropy) were analysed in the course of the experiment. We selected eight plant functional traits (Canopy height, SLA, LDMC, Seed mass, Shoot cyclicity, Clonal index, Onset of flowering, Leaf distribution) capturing the main plant life strategies. Results: Temporal changes, fluctuations and divergences between treatments could be observed in both functional composition and diversity. In particular, the vegetation of the fallow treatment showed strong competition for light and a higher investment into internal nutrient cycling. Over time, all treatments respond towards more stressful conditions due to generally less intensive management compared with the former management and respective nutrient depletion, leading to a more nutrient-retentive and patch-holding strategy and little investment into competitive seedlings. High competition and loose abiotic filters in the fallow treatment led to a niche separation in foliar traits. Mowing on the other hand enforced a divergence of reproduction mechanisms. Conclusion: We detected long-term fluctuations and on-going changes in functional composition and diversity even after 26 yr. Especially early succession was characterized by a transient loss of functional diversity, caused by strong time lags in immigration and extinction of species. Our findings stress the importance of long-term experimental studies to avoid precarious misinterpretations.