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Summary 1.A great deal of money is being invested in calcareous grassland restoration on arable land within agri-environment schemes in the European Union. There is, however, little evidence that the target ecosystem can be obtained from the restoration techniques and management practices currently used. We evaluated these techniques using a multi-site approach in order to improve the success of future restoration efforts. 2. We compared 40 restoration sites with 40 paired reference sites and addressed the following specific hypotheses: (i) Are plant communities of restoration sites becoming more like those of mature calcareous grassland? (ii) How long does the restoration process take? (iii) Are there any environmental filters that hinder the process? (iv) Is there a difference in plant attributes between restored and ancient grassland communities, and between restored communities of different ages? 3. We used a multivariate approach to assess the similarity of sites and found that there was little overlap between restored and ancient grassland communities even after 60 years. Successful restoration of calcareous grasslands is achievable but the process is slow. 4. Different plant attributes were present at different frequencies in restored and reference sites, and the frequency of some attributes became more like those of reference sites with increasing age of restored site (e.g. perenniality and ruderality). 5. Seeding restoration sites with a low diversity mix appeared detrimental to restoration. Sites that regenerated naturally moved towards the target over time, although success was limited by proximity to ancient grassland vegetation. High soil phosphorus concentration was detrimental to restoration. 6. Synthesis and applications . We recommend selecting restoration sites with low phosphorous concentrations that adjoin patches of ancient calcareous grassland. Seed mixes should be devised carefully to prevent the assembly of low-value, competitive, stable communities dominated by grasses; natural regeneration may avoid this, but will only be effective close to sources of propagules. Other methods of restoration or habitat management would undoubtedly benefit from similar multi-site evaluation.

The stability of ecological communities is critical for the stable provisioning of ecosystem services, such as food and forage production, carbon sequestration, and soil fertility. Greater biodiversity is expected to enhance stability across years by decreasing synchrony among species, but the drivers of stability in nature remain poorly resolved. Our analysis of time series from 79 datasets across the world showed that stability was associated more strongly with the degree of synchrony among dominant species than with species richness. The relatively weak influence of species richness is consistent with theory predicting that the effect of richness on stability weakens when synchrony is higher than expected under random fluctuations, which was the case in most communities. Land management, nutrient addition, and climate change treatments had relatively weak and varying effects on stability, modifying how species richness, synchrony, and stability interact. Our results demonstrate the prevalence of biotic drivers on ecosystem stability, with the potential for environmental drivers to alter the intricate relationship among richness, synchrony, and stability.

Fire has been used for centuries to generate and manage some of the UK's cultural landscapes. Despite its complex role in the ecology of UK peatlands and moorlands, there has been a trend of simplifying the narrative around burning to present it as an only ecologically damaging practice. That fire modifies peatland characteristics at a range of scales is clearly understood. Whether these changes are perceived as positive or negative depends upon how trade-offs are made between ecosystem services and the spatial and temporal scales of concern. Here we explore the complex interactions and trade-offs in peatland fire management, evaluating the benefits and costs of managed fire as they are currently understood. We highlight the need for (i) distinguishing between the impacts of fires occurring with differing severity and frequency, and (ii) improved characterization of ecosystem health that incorporates the response and recovery of peatlands to fire. We also explore how recent research has been contextualized within both scientific publications and the wider media and how this can influence non-specialist perceptions. We emphasize the need for an informed, unbiased debate on fire as an ecological management tool that is separated from other aspects of moorland management and from political and economic opinions.This article is part of the themed issue ‘The interaction of fire and mankind’.

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JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. British Ecological Society is collaborating with JSTOR to digitize, preserve and extend access to Journal of Applied Ecology. Summary 1. Lowland heaths are high-profile ecosystems for conservation action in England, but they are under threat from invasion by Betula spp., Pinus sylvestris, Pteridium aquilinum, Rhododendron ponticum and Ulex europaeus. 2. Ten heathland sites in the Poole Basin area of Dorset, where succession to one or other of the above species had occurred, were studied to examine the changes in vegetation and soil chemical properties. 3. A series of hypotheses to explain (i) vegetation successional trajectories, and (ii) soil chemical properties associated with vegetation change were tested using multivariate models (DECORANA -vegetation; CANOCOvegetation and soil). 4. A range of pathways was found along which heathland communities move during succession, with some successional pathways remaining closer to heathland than others. 5. The Betula spp. succession caused the greatest changes in terms of the vegetation present. The Ulex europaeus and Pinus sylvestris trajectories retained some typical heathland species. 6. Different soil nutrients were found to increase along different successional pathways, which were associated with the different successional species invading. 7. Pinus sylvestris had similar soil nutrient concentrations to those of the heathland. Sodium concentrations increased during the Rhododendron ponticum succession. Concentrations of ammonium-nitrogen and nitrate/nitrite-nitrogen increased during the Pteridium aquilinum and Ulex europaeus succession. The Betula spp. had the greatest effect on the soil nutrients with increased pH, extractable phosphorus and exchangeable calcium. 8. The results are discussed in relation to practical heathland management and the restoration of heathland after succession. Specifically, it is more sensible and costeffective to restore heathland on sites where Pinus sylvestris successions have occurred, than where Betula spp. successions have occurred.

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Summary1. The role of prescribed burning of vegetation to manage fire risk is controversial in a variety of situations worldwide. It is becoming more topical (i) as a result of potential global warming where the risk of wildfire might increase and (ii) because fire might affect the various ecosystem services provided in a different way. Where prescribed fire is used, ecologists need to know the impact on biodiversity (post-fire recovery) and on provisioning and regulating services such as water collection and carbon sequestration. Here, we assess the effect of prescribed burning on plant community composition and its component species at the regional scale of the Peak District, where the moorland vegetation is severely degraded. 2. Species cover (%) was assessed on five moors with respect to elapsed time since prescribed burning and vegetation height. A stratified random method was used to choose burn patches covering a range of ages since burning; quadrats were then sampled randomly within these patches over a 3-year period. Detrended correspondence analysis was used to relate species composition to significant environmental variables, and variation partitioning was used to assess their relative contribution. Response curves were produced for the major species with respect to elapsed time since burning and vegetation height. 3. The species ordination produced two gradients, (i) a continuum from a graminoid-dominated vegetation to one dominated by Erica tetralix, Vaccinium myrtillus and Rubus chamaemorus and (ii) a post-fire growth response of the dominant species, Calluna vulgaris. Species composition was more highly correlated with vegetation height than elapsed time since burning. The environmental variables explained 15AE2% of the variation. 4. Calluna vulgaris was the only species to show an increasing response after burning; all others showed an increase immediately after burning, but then they either decreased or showed a unimodal ⁄ skewed response. Most other species were restricted to vegetation <40 cm height and 20-25 years after burning. 5. Synthesis and applications. We found two major results of importance to policy makers and land managers: (i) that prescribed burning maintains species diversity in the immediate post-burn phase, and (ii) as the vegetation ages and increases in height, most species disappear and the vegetation becomes dominated by C. vulgaris. From a policy perspective, prescribed burning (or some other disturbance) is needed to maintain burning and a no-burn policy will result in a low-diversity, C. vulgaris-dominated vegetation. As vegetation height is the easiest measure for land managers to use in judging when to burn, we recommend moorland vegetation be burned before it reaches 25 cm in height to maintain the pre-burn complement of plant species. If the rotation allows the vegetation to become much taller (>40 cm), then most species will be lost and they will have to colonize after subsequent fires from the seedbank or from the surrounding area.