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Harrogate, United Kingdom

de Vere N.,National Botanic Garden of Wales | Rich T.C.G.,National Museum Wales | Ford C.R.,National Botanic Garden of Wales | Trinder S.A.,National Botanic Garden of Wales | And 10 more authors.
PLoS ONE | Year: 2012

We present the first national DNA barcode resource that covers the native flowering plants and conifers for the nation of Wales (1143 species). Using the plant DNA barcode markers rbcL and matK, we have assembled 97.7% coverage for rbcL, 90.2% for matK, and a dual-locus barcode for 89.7% of the native Welsh flora. We have sampled multiple individuals for each species, resulting in 3304 rbcL and 2419 matK sequences. The majority of our samples (85%) are from DNA extracted from herbarium specimens. Recoverability of DNA barcodes is lower using herbarium specimens, compared to freshly collected material, mostly due to lower amplification success, but this is balanced by the increased efficiency of sampling species that have already been collected, identified, and verified by taxonomic experts. The effectiveness of the DNA barcodes for identification (level of discrimination) is assessed using four approaches: the presence of a barcode gap (using pairwise and multiple alignments), formation of monophyletic groups using Neighbour-Joining trees, and sequence similarity in BLASTn searches. These approaches yield similar results, providing relative discrimination levels of 69.4 to 74.9% of all species and 98.6 to 99.8% of genera using both markers. Species discrimination can be further improved using spatially explicit sampling. Mean species discrimination using barcode gap analysis (with a multiple alignment) is 81.6% within 10×10 km squares and 93.3% for 2×2 km squares. Our database of DNA barcodes for Welsh native flowering plants and conifers represents the most complete coverage of any national flora, and offers a valuable platform for a wide range of applications that require accurate species identification. © 2012 de Vere et al. Source

Walker K.J.,Botanical Society of the British Isles | Pinches C.E.,Natural England
Biological Conservation | Year: 2011

In England Pulsatilla vulgaris is a threatened herb that declined from 130 to 33 sites between 1750 and the 1960s due to ploughing-up of calcareous grassland. We examined the subsequent fate of these populations using documentary evidence and field survey. Demographic trends were related to changes in grassland composition, structure and management and responses to increased above-ground competition (caused by reduced grazing) were simulated in a 10-year shading experiment. Since 1968 P. vulgaris has been lost from 16 sites and gradually declined on four others. However, the total population size increased by 258% due to the reintroduction of winter grazing on three sites. This produced a significantly shorter, more herb-rich sward, with a lower cover of Bromopsis erecta (c. 10%), than on sites where populations remained stable or declined. Experimental shading had a significant negative effect on plant survival and flowering performance. These results confirmed that reduced grazing is now one of the major threats to species dependent on short swards, especially on isolated sites where livestock farming is no longer economically viable. That many of these declines took place on nature reserves highlights the difficulties of managing isolated grasslands, and the urgent need to re-instate grazing on reserves supporting populations of threatened species in otherwise intensively managed lowland landscapes. © 2011 Elsevier Ltd. Source

Rapacciuolo G.,Imperial College London | Rapacciuolo G.,UK Center for Ecology and Hydrology | Roy D.B.,UK Center for Ecology and Hydrology | Gillings S.,British Trust for Ornithology | And 3 more authors.
PLoS ONE | Year: 2012

Conservation planners often wish to predict how species distributions will change in response to environmental changes. Species distribution models (SDMs) are the primary tool for making such predictions. Many methods are widely used; however, they all make simplifying assumptions, and predictions can therefore be subject to high uncertainty. With global change well underway, field records of observed range shifts are increasingly being used for testing SDM transferability. We used an unprecedented distribution dataset documenting recent range changes of British vascular plants, birds, and butterflies to test whether correlative SDMs based on climate change provide useful approximations of potential distribution shifts. We modelled past species distributions from climate using nine single techniques and a consensus approach, and projected the geographical extent of these models to a more recent time period based on climate change; we then compared model predictions with recent observed distributions in order to estimate the temporal transferability and prediction accuracy of our models. We also evaluated the relative effect of methodological and taxonomic variation on the performance of SDMs. Models showed good transferability in time when assessed using widespread metrics of accuracy. However, models had low accuracy to predict where occupancy status changed between time periods, especially for declining species. Model performance varied greatly among species within major taxa, but there was also considerable variation among modelling frameworks. Past climatic associations of British species distributions retain a high explanatory power when transferred to recent time - due to their accuracy to predict large areas retained by species - but fail to capture relevant predictors of change. We strongly emphasize the need for caution when using SDMs to predict shifts in species distributions: high explanatory power on temporally-independent records - as assessed using widespread metrics - need not indicate a model's ability to predict the future. © 2012 Rapacciuolo et al. Source

Redhead J.W.,UK Center for Ecology and Hydrology | Sheail J.,UK Center for Ecology and Hydrology | Bullock J.M.,UK Center for Ecology and Hydrology | Ferreruela A.,Forestal Catalana | And 2 more authors.
Applied Vegetation Science | Year: 2014

Questions: What is the time-scale for natural regeneration of calcareous grassland? Is this time-scale the same for individual plant species, plant community composition and functional traits? Location: Defence Training Estate Salisbury Plain, Wiltshire, UK. Methods: We investigated the rate of natural regeneration of species-rich calcareous grassland across a 20 000-ha landscape. We combined a large-scale botanical survey with historic land-use data (6-150 yrs before present) and examined differences between grassland age classes in the occurrence of individual plant species, plant community composition and plant community functional traits. Results: Many species showed a significant association with grasslands over 100 yrs old. These included the majority of those defined elsewhere as calcareous grassland indicators, although some appeared on grasslands <10 yrs old. Plant community composition showed increasing similarity to the oldest grasslands with increased grassland age, with the exception of very recently ex-agricultural grasslands. Most functional traits showed clear trends with grassland age, with dispersal ability differing most strongly between recent and older grasslands, whilst soil fertility and pH tolerance were more influential over longer time-scales. Conclusions: Even in a well connected landscape, natural regeneration to a community resembling ancient calcareous grassland in terms of functional traits and plant community composition takes over a century, although changes at the level of individual species may occur much earlier. These findings confirm the uniqueness of ancient calcareous grassland. They also suggest that the targets of re-establishment efforts should be adjusted to account for the likely time-scale of full community re-assembly. We examined natural regeneration in an extensive calcareous grassland landscape over a 150 yrs timescale. Results showed that natural regeneration takes over a century when measured by functional traits and plant community composition, despite comparatively rapid changes in the occurrence of individual species. These findings emphasize the value of existing ancient calcareous grasslands and the challenges facing restoration efforts. © 2013 International Association for Vegetation Science. Source

Roy H.E.,UK Center for Ecology and Hydrology | Preston C.D.,UK Center for Ecology and Hydrology | Harrower C.A.,UK Center for Ecology and Hydrology | Rorke S.L.,UK Center for Ecology and Hydrology | And 11 more authors.
Biological Invasions | Year: 2014

Information on non-native species (NNS) is often scattered among a multitude of sources, such as regional and national databases, peer-reviewed and grey literature, unpublished research projects, institutional datasets and with taxonomic experts. Here we report on the development of a database designed for the collation of information in Britain. The project involved working with volunteer experts to populate a database of NNS (hereafter called "the species register"). Each species occupies a row within the database with information on aspects of the species' biology such as environment (marine, freshwater, terrestrial etc.), functional type (predator, parasite etc.), habitats occupied in the invaded range (using EUNIS classification), invasion pathways, establishment status in Britain and impacts. The information is delivered through the Great Britain Non-Native Species Information Portal hosted by the Non-Native Species Secretariat. By the end of 2011 there were 1958 established NNS in Britain. There has been a dramatic increase over time in the rate of NNS arriving in Britain and those becoming established. The majority of established NNS are higher plants (1,376 species). Insects are the next most numerous group (344 species) followed by non-insect invertebrates (158 species), vertebrates (50 species), algae (24 species) and lower plants (6 species). Inventories of NNS are seen as an essential tool in the management of biological invasions. The use of such lists is diverse and far-reaching. However, the increasing number of new arrivals highlights both the dynamic nature of invasions and the importance of updating NNS inventories. © 2014 Springer International Publishing Switzerland. Source

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