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Question: Below-ground processes are key determinants of above-ground plant population and community dynamics. Still, our understanding of how environmental drivers shape plant communities is mostly based on above-ground diversity patterns, bypassing below-ground plant diversity stored in seed banks. As seed banks may shape above-ground plant communities, we question whether concurrently analysing the above- and below-ground species assemblages may potentially enhance our understanding of community responses to environmental variation. Location: Temperate deciduous forests along a 2000 km latitudinal gradient in NW Europe. Methods: Herb layer, seed bank and local environmental data including soil pH, canopy cover, forest cover continuity and time since last canopy disturbance were collected in 129 temperate deciduous forest plots. We quantified herb layer and seed bank diversity per plot and evaluated how environmental variation structured community diversity in the herb layer, seed bank and the combined herb layer–seed bank community. Results: Seed banks consistently held more plant species than the herb layer. How local plot diversity was partitioned across the herb layer and seed bank was mediated by environmental variation in drivers serving as proxies of light availability. The herb layer and seed bank contained an ever smaller and ever larger share of local diversity, respectively, as both canopy cover and time since last canopy disturbance decreased. Species richness and β-diversity of the combined herb layer–seed bank community responded distinctly differently compared to the separate assemblages in response to environmental variation in, e.g. forest cover continuity and canopy cover. Conclusions: The seed bank is a below-ground diversity reservoir of the herbaceous forest community, which interacts with the herb layer, although constrained by environmental variation in e.g. light availability. The herb layer and seed bank co-exist as a single community by m

We sought to identify predictors of symptomatic recovery in Vestibular Neuritis (VN). Forty VN patients were prospectively studied in the acute phase (median=2 days) and 32 in the recovery phase (median=10 weeks) with vestibulo-ocular reflex, vestibular-perceptual and visual dependence tests and psychological questionnaires. Clinical outcome was Dizziness Handicap Inventory score at recovery phase. Acute visual dependency and autonomic arousal predicted outcome. Worse recovery was associated with a combination of increased visual dependence, autonomic arousal, anxiety/depression and fear of bodily sensations, but not with vestibular variables. Findings highlight the importance of early identification of abnormal visual dependency and concurrent anxiety.

Underwater video is increasingly being used to record and research aquatic fauna in their natural environment, and is emerging alongside Dual Frequency Identification Sonar (DIDSON) as a powerful tool in Australian freshwater ecology. We review current progress with field-based applications of underwater video in studying Australian freshwater fish and crustacean ecology. Drawing upon searches of online literature databases and our expert knowledge, we located 11 relevant publications: five set in the Murray-Darling Basin, three in the Eastern Province, two in the Northern Province and a single study in the Pilbara Province. In total, 10 studies reported using video for fish ecology, while three studies included crustaceans. Across the 11 publications, eight examined threatened species, while the remaining studies developed video techniques for surveying species richness in remote or difficult to access habitats. Habitat-use was also a dominant theme (seven studies). Seven of the eight studies that centred on threatened species focused on at least one percichthyid species in either the Murray-Darling Basin or the Eastern Province. Miniaturisation in equipment and increases in compact battery capacity seem to have driven a shift from above-water battery supplies and data storage to small, inexpensive and mobile underwater cameras. We foresee wider use of video in freshwater ecology primarily in the study of animal behaviour and also to improve species detection in field surveys. There is scope for testing novel techniques such as animal-borne video and unmanned underwater vehicles and making use of video in citizen science initiatives.

Climate warming is already influencing plant migration in different parts of the world. Numerous models have been developed to forecast future plant distributions. Few studies, however, have investigated the potential effect of warming on the reproductive output of plants. Understorey forest herbs in particular, have received little attention in the debate on climate change impacts. This study focuses on the effect of temperature on sexual reproductive output (number of seeds, seed mass, germination percentage and seedling mass) of Anemone nemorosa L., a model species for slow colonizing herbaceous forest plants. We sampled seeds of A. nemorosa in populations along a 2400 km latitudinal gradient from northern France to northern Sweden during three growing seasons (2005, 2006 and 2008). This study design allowed us to isolate the effects of accumulated temperature (Growing Degree Hours; GDH) from latitude and the local abiotic and biotic environment. Germination and seed sowing trials were performed in incubators, a greenhouse and under field conditions in a forest. Finally, we disentangled correlations between the different reproductive traits of A. nemorosa along the latitudinal gradient. We found a clear positive relationship between accumulated temperature and seed and seedling traits: reproductive output of A. nemorosa improved with increasing GDH along the latitudinal gradient. Seed mass and seedling mass, for instance, increased by 9.7% and 10.4%, respectively, for every 1000 °C h increase in GDH. We also derived strong correlations between several seed and seedling traits both under field conditions and in incubators. Our results indicate that seed mass, incubator-based germination percentage (Germ%Inc) and the output of germinable seeds (product of number of seeds and Germ%Inc divided by 100) from plants grown along a latitudinal gradient (i.e. at different temperature regimes) provide valuable proxies to parameterize key population processes in models. We c

1. Ex-arable fields have been suggested as potential sites for re-creation of semi-natural grasslands, but information is still limited on the temporal scales needed for the natural assembly of these communities and whether colonization is related to dispersal or establishment limitation. 2. We investigated grazed ex-arable fields of different age and adjacent semi-natural grasslands in terms of species richness of plants, community similarity, colonization pattern and recruitment ability of 16 sown grassland species. The functional trait distribution of successful and unsuccessful colonizing species was compared using five traits related to dispersal and persistence: seed mass, seed bank persistence, specific leaf area, plant height and potential for lateral spread. 3. The youngest ex-arable fields had the lowest species richness and contained communities with the lowest similarity to semi-natural grassland. Species richness and similarity to semi-natural grassland both increased with time since grazing started on ex-arable fields, but were still significantly lower than in semi-natural grasslands even after more than 50 years of grazing. 4. Colonization was not related to any of the investigated functional traits. The rank order of the species in terms of abundance was correlated between young and old ex-arable fields suggesting that species performance remains the same with field age. 5. Recruitment after sowing was generally lower in ex-arable fields than in semi-natural grasslands, although the basic recruitment ability varied between species. Recruitment did not change with field age, suggesting that dispersal limitation rather than establishment limitation caused the temporal pattern of colonization. However, establishment limitation may act as a filter for colonization of all ex-arable fields, regardless of their age. 6. Synthesis and applications. This study demonstrates that the temporal scale for natural assembly of semi-natural grassland communities in e

Semi-natural grasslands in Sweden are threatened by land-use change and lack of management with attendant risk to their biodiversity. We present a model to explore the effects of grazing frequency and intensity on plant species persistence, and the relative effects of grassland size and pattern. We used a landscape modelling platform, LAMOS (LAndscape MOdelling Shell), to design a landscape model of vegetation dynamics incorporating the effects of local succession, dispersal and grazing disturbance. Five plant functional groups (PFG), representing various combinations of persistence and dispersal character, light requirements and disturbance responses, were defined to model species dynamics. Based on old cadastral maps three different landscapes were designed representing specific time-layers, i.e., a historical (17th to 18th century), a pre-modern (1940s) and a present-day landscape. Simulations showed that a threshold was crossed when grasslands decreased in area to about 10-30% of the modelled area, and as a consequence the biomass of grassland-specific PFGs was strongly reduced. These competition sensitive groups did not persist in the model even with intense grazing in the present-day landscape, where grasslands occupy 11% of the total area. However, all grassland species would have been able to persist in the historical landscape, where grasslands occupied 59% of the total area, even without grazing. Our results suggest that continuous but low-intensity grazing is more positive for grassland PFGs than discontinuous but highly intensive grazing. This effect was particularly strong when the frequency and/or intensity of grazing dropped below a threshold of 20%. Simulations using three landscape maps designed to explore effects of further fragmentation and habitat loss showed that the spatial pattern of remaining grasslands is important for the persistence of grassland-specific PFG. The model presented here is an advance towards more realistic grazing models to e