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Salford, United Kingdom

Ormerod S.J.,University of Cardiff | Dobson M.,The Landing | Hildrew A.G.,Queen Mary, University of London | Townsend C.R.,University of Otago
Freshwater Biology

The fundamental importance of freshwater resources, the rapid extinction rate among freshwater species and the pronounced sensitivity of freshwater ecosystems to climate change together signal a pre-eminent need for renewed scientific focus and greater resources. Against this background, the Freshwater Biological Association in 2008 launched a new series of 'summit' Conferences in Aquatic Biology intended to develop and showcase the application of ecological science to major issues in freshwater management. 2. This collection of studies arose from the first summit entitled 'Multiple Stressors in Freshwater Ecosystems'. Although freshwater science and management are replete with mutiple-stressor problems, few studies have been designed explicitly to untangle their effects. 3. The individual case studies that follow reveal the wide array of freshwaters affected by multiple stressors, the spatial and temporal scales involved, the species and ecosystem processes affected, the complex interactions between ecology and socioeconomics that engender such effects, the approaches advocated to address the problems and the challenges of restoring affected systems. The studies also illustrate the extent to which new challenges are emerging (e.g. through climate change), but also they develop a vision of how freshwaters might be managed sustainably to offset multiple stressors in future. 4. More generically, these case studies illustrate (i) how freshwaters might be at particular risk of multiple-stressor effects because of conflicts in water use, and because the hydrological cycle vectors stressor effects so effectively and so extensively; (ii) that dramatic, nonlinear, 'ecological surprises' sometimes emerge as multiple-stressor effects develop and (iii) that good ecology and good ecologists add considerable value to other freshwater disciplines in understanding multiple stressors and managing their effects. © 2010 Blackwell Publishing Ltd. Source

The freshwater pearl mussel (Margaritifera margaritifera) is declining throughout its entire range. On the river Rede, North-East England, the population has been equally declining and shows no apparent recruitment. The study presented here aimed at characterizing water quality and habitat conditions for pearl mussels to identify possible indicators of pressures on the population and inform a restoration and conservation strategy. Water quality monitoring revealed levels of turbidity and suspended sediments to be above the limit set for functional pearl mussel rivers. Substrate sampling revealed silt was present at all sites. A loss of redox potential between the water column and the substrate occurred at all sites, indicating non suitable conditions for juvenile pearl mussels. These investigations suggest that fine sediment input in the river could be one of the factors preventing the development and survival of juvenile mussels while adults face water quality largely affected by high turbidity and high phosphate load. Restoration strategy for the Rede pearl mussel population should focus mainly on limiting sediment and nutrient input in the river throughout the catchment in order to improve habitat for juvenile pearl mussels. This work highlights the need for a catchment-based approach in order to succeed in the conservation of a fragile species. © 2014 Elsevier GmbH. Source

From eastern North America, the glandular pubescent variety of Osmunda cinnamomea L. var. glandulosa Waters (Osmundaceae) is transferred as Osmundastrum cinnamomeum (L.) C. Presl var. glandulosum (Waters) McAvoy. Copyright © 2011 BioOne All rights reserved. Source

Croope S.V.,The Landing | McNeil S.,University of Delaware
Transportation Research Record

The nation's capacity for maintenance and improvement of infrastructure systems and its ability to maintain and improve infrastructure systems and ensure the continued service of critical infrastructure systems are receiving special attention because recent disasters have had a significant impact on critical infrastructure. These critical infrastructure systems are the foundation of the nation's economic and social systems. Much research and many policy studies have been conducted to develop methods to improve protection of critical infrastructure with a focus on decreased vulnerability. This paper describes the development of a framework for a decision support system. The objective of the decision support system is to reduce the vulnerability of places and infrastructure systems through the use of mitigation strategies that increase system resilience and resistance to the stresses imposed by disasters. The decision support system will also provide an understanding of the many variables involved in developing strategies to improve the resilience of critical infrastructure systems. This decision support system, referred to as the Critical Infrastructure Resilience Decision Support System (CIR-DSS), uses systems dynamics and recognizes the impacts of disasters, including damage and disruption to critical infrastructure. Results include those of risk and cost-benefit analyses of alternative strategies that also recognize U.S. government policies for recovery and mitigation. A case study focused on transportation infrastructure was used to test and validate the CIR-DSS framework. Source

Petersen E.L.,The Landing
IEEE Transactions on Nuclear Science

We compare the statistical errors in single event experiments at various facilities. It is possible to have systematic standard deviations in the data as large as 90%, and to have errors of 35% when the desired values are less than 10%. In general the systematic errors in dosimetry are much larger than the statistical errors in the data points. Observation of the dosimetry errors should be a major part of the data analysis. We examine several experiments that compared ionization induced errors by low energy ions and high energy ions at different facilities. They are consistent in showing that the results do not depend on ion or energy. © 2010 IEEE. Source

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