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Questions: Seedling recruitment is a key step in any seed‐based ecological restoration project. There is a controversial discussion (a) whether soil preparation is required to reduce competition of pre‐existing vegetation, or whether vegetation cover facilitate seedling recruitment, and (b) whether grazing should be excluded in initial stages of grassland restoration to protect seedlings, because grazing exclusion may also favour competitive ruderal species. We set up a combined soil preparation and grazing experiment to evaluate the effect of both factors on seedling recruitment of seeds transferred from a species‐rich donor site. Location: Upper Durance valley, Hautes‐Alpes, France. Methods: The experiment was set up using a full factorial split‐plot design with five replicate sites. The treatments included soil preparation (harrowed or not) and grazing (excluded or not). Seeds were transferred using plant material brushed in a non‐degraded reference grassland. The individuals of all occurring species were counted on the restoration sites, and the survival and reproduction of two focal species, Bromopsis erecta and Rhinanthus alectorolophus, were recorded for three months. Results: Soil preparation by harrowing reduced the density of spontaneously emerging species and increased the seedling density of species transferred from the donor site. Grazing had only a weak negative effect on the recruitment of transferred species. The main effect of both treatments on seedling survival was not significant, but a significant interaction indicated that the grazing effect depended on soil preparation, with a negative effect of grazing only in non‐harrowed plots. Conclusions: The reduction of competition by soil preparation before seed addition of brush material had a positive effect on the seedling recruitment of transferred species and can thus clearly be recommended in our study system. The weak negative effect of grazing may not always justify fencing costs. [ABSTRACT FROM AUTHOR]

Question: Salvage logging and prescribed fire are commonly applied in forests worldwide, yet little is known about the combined impacts of these management actions on early‐successional ecosystems. We questioned how operational‐scale prescribed fire would affect ground flora cover, species diversity, and life‐history trait expression in Pinus palustris woodlands differentially impacted by an Enhanced Fujita scale 3 (EF3) tornado and salvage logging. Location: Fall Line Hills, Alabama, USA (32°55ʹ30ʺ N, 87°24ʹ00ʺ W). Methods: The composition and foliar cover of woody and herbaceous plants ≤1 m height were monitored before and after prescribed fire in 600 1‐m2 quadrats distributed throughout mature, wind‐disturbed, and salvage‐logged Pinus palustris woodlands. Plant taxa were categorized by growth habit and life form to aid interpretation of multivariate analyses used to illustrate differences in ground flora assemblages between disturbance categories. Results: Prescribed fire reduced ground flora cover, but not diversity, which remained greatest in wind‐disturbed sites that were not salvage‐logged. Though ground flora assemblages remained disparate between disturbance categories, prescribed fire imposed some consistent selective pressures on plants with common life‐history strategies. Post‐fire understorey tree cover reductions coincided with increased shrub cover throughout the treatment area. Nonetheless, differences in graminoid cover were exaggerated after prescribed fire, and representation of the geophyte life form was relatively constant across space and time. Conclusions: Prescribed fire did not counteract salvage‐mediated reductions in ground flora diversity. Retention of downed deadwood maximized early‐successional plant diversity in wind‐disturbed sites. Trait‐based ground flora analyses enabled a more detailed understanding of disturbance effects than aggregate metrics of foliar cover and diversity. In ecosystems with high floristic diversity, grouping plants by common life‐history traits can provide a simple and effective means to monitor impacts of management actions on ecosystem recovery. [ABSTRACT FROM AUTHOR]

Questions: Restoring grasslands is of great importance to biodiversity conservation to counteract widespread, ongoing losses of plant species diversity. Using source populations in remnant habitats and increasing functional connectivity mediated by grazing animals within and between habitats can benefit grassland restoration efforts. Here we investigate how grazing contributes to vegetation and seed bank diversity and composition in remnant and restored grassland communities in fragmented landscapes. Location: Stockholm archipelago, Sweden. Methods: We investigated the effects of the presence or absence of grazing animals as potential elements of functional connectivity on grassland species composition in both the vegetation layer and in the seed bank. Species inventory and seed bank sampling were carried out in 2 m × 2 m plots in remnant grassland habitats and adjacent restored grasslands on former arable fields. Results: Species composition varied between remnant and restored grasslands, with management‐dependent species more common in remnant grasslands. Remnant habitats with active grazing management contained a higher number of species in both the vegetation and seed bank compared to restored grasslands, but grazing reduced dispersal limitation from higher distance to source populations for specialist species. Where grazing was absent fewer plant species occurred in both the vegetation and in the seed bank. Conclusion: Our results show that grazing livestock play a key role in facilitating both spatial and temporal dispersal in fragmented grasslands. This results in increased species diversity in the vegetation and the seed bank of grazed grasslands compared to those maintained by mowing only. Functional connectivity provided by grazing management increases the possibility for species establishment from both the below‐ground seed bank and the surrounding landscape, thus increasing the resilience of plant communities against disturbances or climatic changes. [ABSTRACT FROM AUTHOR]

Questions: How are dispersal processes, abiotic and biotic interactions determining the initial salt marsh plant community establishment and development when connectivity is different? We aim to answer this question by analysing the spatial and temporal patterns of plant establishment along an environmental gradient at two connectivity settings. Location: Back‐barrier salt marsh and tidal flats of Spiekeroog, northwest Germany. Methods: We established an experiment along a saltmarsh elevation gradient with bare sediment open for spontaneous colonisation on the natural salt marsh and on the experimental salt marsh islands built on the tidal flats approximately 500 m from the natural salt marsh for low connectivity. Plant establishment was identified from georeferenced photos at least monthly. Results: Experimental islands as low‐connectivity plots had limited colonisation by annual halophytes that produced large number of small seeds. Number of individuals increased with higher connectivity at patches enclosed by salt marsh. Number of individuals was highest at the mid elevations whereas peak species richness was at the upper salt marsh. Temporal patterns of seedling emergence showed increasing plant numbers until the end of April followed by a gradual decline over the season at the pioneer and lower salt marsh zones. Upper elevations on the other hand had a stable number of low individual counts over time. Spatial clustering of plant individuals indicating possible facilitation was important at the initial stages of salt marsh development at pioneer and lower salt marsh elevation, but only early in the season. Conclusions: Stochastic patterns of early salt marsh colonisation indicated that success of species colonisation was determined by seed properties, seed availability and environmental conditions mediated by elevation. We found indications that at the initial stages, further colonisation was supported by already colonised plants but shifted to avoidance later in the season. [ABSTRACT FROM AUTHOR]

Questions: Germination is a prerequisite of successful establishment in plant communities and is influenced by many factors. Therefore, seeds are under strong selective pressure to sense and integrate information about their environment and modulate germination based on it. In this study, we focus on interspecific seed–seed interactions under optimal and suboptimal conditions to test three hypotheses: (H1) dominant species' seeds and emerging seedlings are most likely to be recognised by neighbouring seeds and exert a significant effect on the germination of common subordinate species; (H2) taxonomically related species are expected to exert stronger influence than unrelated species on the germination of neighbouring seeds; and (H3) facilitative interactions are more likely to occur under suboptimal conditions (drought stress) in the seed–seed interactions. Location: Semi‐dry temperate grassland belonging to the Festuco‐Brometea class, Cluj‐Napoca, Romania. Methods: We assessed the rate and speed of germination of three common subordinate Asteraceae species (target species) in a controlled germination experiment. The target species' seeds were sown in combination with low and high densities of neighbour species: two dominant Poaceae species, two subordinate Asteraceae species and two subordinate Apiaceae species; under optimal or drought conditions. Results: Under optimal water conditions, particularly the seeds of the two dominant Poaceae species affected the germination of target species. Under drought stress, almost all neighbouring species altered the germination of two of the target species, enhancing or reducing their germination rate. Facilitation in seed–seed interactions was proved to be species‐specific rather than general under drought conditions. Conclusions: We found evidence that the status in a plant community (dominant or subordinate), but not the taxonomic relatedness influences the outcome of seed–seed interactions during germination. Under drought stress, the persistent competitive effect of the dominant species might considerably hinder the recruitment of subordinate grassland species. [ABSTRACT FROM AUTHOR]

Questions: Anthropogenic disturbances are known to be followed by extremely poor recovery in edaphic grasslands. However, the role of interactions with diaspore predators and secondary dispersers, which compose the dispersal filter and modulate plant community recovery, has been overlooked. We performed field experiments to investigate how soil disturbances affect diaspore interactions with the ground‐foraging fauna to better understand how disturbance influences regeneration potential. Location: Campo rupestre vegetation, megadiverse edaphic grasslands, southeastern Brazil. Methods: We used diaspores from five native species to compare removal rates between disturbed (top soil removal) and preserved sites; we also controlled invertebrate and vertebrate access to determine their role. In addition, we assessed differences in the diaspore removal effectiveness (DRE) and the structure of animal–diaspore interactions through network based‐approach. Results: For three species, the average diaspore removal rates was relatively high (between 30% and 70%). Invertebrates were the most common removal agents in both disturbed and preserved sites. Interactions with foraging fauna and removal rates were 20% smaller in disturbed sites. Considering all diaspore removal events in disturbed sites, 24% resulted in the displacement from disturbed to preserved sites, but no diaspore was transported from preserved to disturbed ones. The animal–diaspore network was exclusively composed by ant–diaspore interactions and was more diverse and robust in preserved sites compared with disturbed ones. Seed predator ants (Pheidole and Dorymyrmex) were more common in disturbed sites. Furthermore, significant differences were found in the DRE between ant species and site types, suggesting specificity in the provision of dispersal services. Conclusions: Topsoil removal affected removal proportions, DRE and ant–diaspore interaction network structure. The lack of diaspore dispersal towards disturbed sites indicates that soil removal affects secondary seed removal dynamics, impeding recovery potential. Disturbance negatively affected diaspore fate by reshaping interactions with ground‐foraging secondary seed dispersers and predators, constraining the development of seed bank and thus impacting upon vegetation dynamics and resilience. [ABSTRACT FROM AUTHOR]

Questions: Vegetative re‐sprouting and recruitment from seed determine grassland recovery after severe drought, but the mechanisms determining vegetation composition are not fully understood. We ask how the timing of drought and seed availability modify the drought legacy effects on composition and function in a temperate, semi‐natural grassland. Location: Negrentino, southern Alps, Switzerland. Methods: Under automated rainout shelters, we simulated extreme seasonal drought events in a late summer and in the following spring, added rainwater to simulate normal conditions in no‐drought controls and maintained haymaking at times of normal practice. Towards the end of the summer drought, we added seeds of ten local species in a three‐factor split‐plot arrangement with seven blocks as the replicated unit. We measured fine‐scale variation in soil depth. We assessed the biomass of graminoids and forbs at regular harvesting dates and the species frequencies of established plants and recruits before treatment start, repeating these assessments for three years thereafter. We measured the biomass proportions of post‐drought annual recruit cohorts in year 4 after drought. Results: One‐time seed addition augmented recruits, modified species composition and enhanced species diversity; these effects propagated to increased reproductive shoots of recruits and community biomass four years later. Single and repeated seasonal droughts only caused low adult plant mortality but clearly reduced recruitment from seed, while post‐drought establishment was slightly enhanced. Seed augmentation compensated the negative spring drought effect on forb recruits and in turn mitigated the negative impact of drought on species diversity after drought. Conclusions: Our experiment shows that seed deficiency limits productivity and that seed deficiency compensation can help to stabilize diversity and productivity in semi‐natural grassland. Releasing the current constraints of management on seed supply in grassland would therefore assist in mitigating negative drought impacts. [ABSTRACT FROM AUTHOR]

Vitamin D is an important nutrient involved in many fundamental health outcomes. However, its influence on female reproductive function remains ambiguous. Cholecalciferol seems to have a role in the reproductive processes and in the patients affected by polycystic ovary syndrome, endometriosis, uterine myomas and premature ovarian failure. Moreover, it may play an important role in the assisted reproductive techniques, given that it is capable of influencing oocyte quality, but also an adequate preparation of the endometrium for embryonic implantation. Although promising, available evidence is based on a limited number of in vitro, in vivo and clinical studies. We provide an overview of the association between vitamin D and female infertility reporting the most recent data published in the literature. Nevertheless, properly randomised clinical trials are mandatory to achieve more conclusive results about the promising role of vitamin D in the management of female assisted reproduction. [ABSTRACT FROM AUTHOR]