12 research outputs found

    ESTUARINE CHEMICAL REACTIVITY AT THE PARTICLE-WATER INTERFACE

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    Merged with duplicate record 10026.1/1768 on 14.02.2017 by CS (TIS)A systematic study of the microstructures of particulate material from the Tamar Estuary using a BET nitrogen adsorption technique has been carried out. The results showed that suspended material had a higher BET surface area (approximately 20m² / g ) than the associated sediments (approximately 13m² / g) . Also the BET surface areas (8-20m² / g) of suspended material collected during axial transects (S = 0-30°/oo) of the Tamar Estuary indicated relatively higher BET surface areas in the turbidity maximum zone as compared to material from up or down estuary. The BET surface areas were inversely related to the carbon content of the particles and although the role of Fe and Mn coatings was examined no definitive relationship to BET surface area was evident. Analysis of nitrogen adsorption-desorption hysteresis loops indicated the pores to be of the parallel plate or slit type in the size range <2-50 nm. The shape and dimensions of these pores would accomodate the penetration of metal ions, like Zn and Cu, into the pore spaces in the particle matrix. A method was designed to enable the analysis of natural Zn and Cu concentrations in small volumes extracted from a reactor on a timescale suitable for kinetic analysis. Dissolved Cu and Zn adsorption-desorption experiments were carried out under controlled conditions using Tamar suspended solids as the adsorbents. The uptake and release profiles were interpreted in terms of a two stage reaction mechanism which involved both surface adsorption and solid state diffusion into the pores. Rate constants were derived from a kinetic analysis to enable evaluation of the chemical timescales of the sorption reactions. When compared to field data of Zn distributions in the Tamar Estuary the time constants allowed a reasoned explanation of the observations. They also pointed to a strong coupling between the physical and chemical timescales within estuaries. This work has indicated an association between trace metal sorption reaction rates and estuarine particle microstructure. These rate constants are of value in the refinement of hydrodynamic models and this study has implications for the availability of trace metals for biological or chemical remobilisation.Institute for Marine Environmental Research, Prospect Place, The Hoe PLYMOUT

    Development and use of Bacteroides 16S rRNA polymerase chain reaction assay for source tracking dog faecal pollution in bathing waters

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    Faecal pollution on bathing beaches poses a potential threat to human health and as a result may also negatively affect the local economy. In instances where the source of such pollution is not obvious, it may be necessary to track such sources using a host-specific genetic markers technique. Bacteroides species are potential indicators for source tracking of faecal pollution in bathing waters. This study designed specific primer sets to amplify sections of the 16S rRNA gene unique to Bacteroides from domestic dogs and used quantitative PCR (qPCR) to quantify such genetic markers in environmental samples. The sensitivity and specificity of the primer sets was determined; they were specific in silico against known dog Bacteroides sequences and in vitro against Bacteroides sequences originating from human and livestock faeces. Dog faecal Bacteroides contamination was then detected in sea water during the bathing season at a local beach where dogs are banned during the summer months, in spite of the fact that these waters had met EU directive standards based on the culture-based enumeration of faecal indicator bacteria. Quantitative PCR was used to determine the limit of detection (LOD) of the dog Bacteroides genetic markers in these water samples. The copy number of dog Bacteroides genetic markers in the water was low and the LOD of those markers was 4 copies per reaction. The use of these dog primers has the potential to supply important additional information when source tracking faecal pollution at bathing beaches and maintaining water quality

    Public perceptions of management priorities for the English Channel region

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    The English Channel region is an area of high conservational importance, as well being a contributor to economic prosperity, social well-being and quality of life of the people living around it. There is a need to incorporate societal elements into marine and coastal governance, to improve management of the Channel ecosystem. Public Perception Research (PPR) is a relatively unexplored dimension of marine science, with limited research at the scale of the Channel region. Using an online survey, this study examined the public’s use of, and funding priorities for, the Channel’s marine and coastal environment. It revealed that there are variations in how the English and French coastlines are used. Environmental issues were generally viewed as being more important than economic ones. Country-level differences were observed for public uses of, and priorities for the Channel region. Cleaner water and beaches, and improved coastal flood defences, were more highly prioritised by English respondents, while offshore renewable energy and sustainability of businesses were more highly prioritised by French respondents. The paper contributes to the debate on the value of PPR by addressing evidence gaps in the English Channel region, and to PPR literature more broadly. It provides baseline data to inform future engagement strategies for the marine and coastal governance of the Channel region specifically. It also identifies how this type of research has implications for the wider marine and coastal environment, including contributing to Sustainable Development Goal 14 on conserving and sustainably using the oceans, seas, and marine resources

    Species distribution modelling to support marine conservation planning

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    This thesis explores some important practical considerations concerning the use of species distribution models in marine conservation planning. Using geo-referenced gorgonian distribution data, together with explanatory environmental variables, predictive models have been used to map the spatial distribution of suitable gorgonian (sea fan) habitat in two study sites; Hatton Bank, in the Northeast Atlantic, and Lyme Bay on the south coast of Devon. Generalized Linear Models (GLMs), Generalized Additive Models (GAMs) and a Maximum Entropy (Maxent) model have been used to support critical investigation into important model considerations that have received inadequate attention in the marine environment. The influence of environmental data resolution on model performance has been explored with specific reference to available datasets in the nearshore and offshore environments. The transferability of deep-sea models has been similarly appraised, with recommendations as to the appropriate use of transferred models. Investigating these practical issues will allow managers to make informed decisions with respect to the best and most appropriate use of existing data. This study has also used novel approaches and investigated their suitability for marine conservation planning, including the use of model classification error in the spatial prioritisation of monitoring sites, and the adaptation of an existing presence-only modelling method to include absence data. Together, these studies contribute both practical recommendations for marine conservation planning and novel applications within the wider species distribution modelling discipline, and consider the implications of these developments for managers, to ensure the ongoing improvement and development of models to support conservation planning.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Constructs of sustainability in coastal management

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    'Sustainability' figures routinely but prominently as a guiding principle for all those working in coastal management. In order to be able to progress coastal sustainability, it is necessary to understand more fully the normative structure of the concept by breaking down the key constructs inherent in the definition of sustainability. To this end a short questionnaire was disseminated to an 'expert' group of coastal and resource management professionals. The data gathered was analysed using the Qualitative Research Solutions (QSR) package, Nud*ist 6, and highlighted a number of theoretical concepts that were commonly held to be determinative of sustainability. These may form the basis for the future development of a 'Coastal Sustainability Standard'.Sustainability Mobile constructs/concepts Success Integrated coastal management

    Using ecosystem service assessments to support participatory marine spatial planning

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    With growing interest in ocean uses for sustainable economic development, there is an increasing need for cross-sectoral marine spatial planning to balance different resource uses and conservation requirements. Ecosystem service assessments can provide the evidence to inform marine spatial planning decisions. Existing case studies suggest that these assessments can also have positive effects on the engagement of marine stakeholders in management and planning processes. Stakeholder engagement is a central element in marine spatial planning and other area-based management approaches. However, in a marine context, engagement is often difficult due to the lack of clear boundaries in the ocean, traditionally sectoral marine management and limited understanding of marine ecosystems. The study presented here investigated ecosystem service assessments as a tool for improving marine stakeholder engagement. Stakeholder experiences with ecosystem service assessments in six marine management and planning case studies were analysed to identify why, how and under what conditions ecosystem service assessments can support effective engagement. The findings show that under the right conditions, ecosystem service assessments can provide an inclusive and integrative platform for engagement, enable a better understanding of marine ecosystems, human-ecosystem interactions and management contexts, and support better stakeholder relationships. Stakeholder participation also improves the evidence base for ecosystem service assessments. Thus, involving stakeholders in ecosystem service assessments can improve marine spatial planning decisions and lead to better management and conservation outcomes for the ocean

    A Systems Approach Framework for the Transition to Sustainable Development: Potential Value Based on Coastal Experiments

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    This article explores the value of the Systems Approach Framework (SAF) as a tool for the transition to sustainable development in coastal zone systems, based on 18 study sites in Europe, where the SAF was developed and tested. The knowledge gained from these experiments concerns the practical aspects of (a) governance in terms of policy effectiveness, (b) sustainability science in terms of applying transdisciplinary science to social-ecological problems, and (c) simulation analysis in terms of quantifying dysfunctions in complex systems. This new knowledge can help broaden our perspectives on how research can be changed to better serve society. The infusion of systems thinking into research and policy making leads to a preference for multi-issue instead of single-issue studies, an expansion from static to dynamic indicators, an understanding of the boundaries between system-dependent and system-independent problems, and the inclusion of non-market evaluations. It also develops a real partnership among research, management, and stakeholders to establish a quantitative basis for collaborative decision making. Furthermore, the article argues that the transition to sustainable development for coastal systems requires consideration of the scale interdependency from individual to global and recognition of the probable global reorganizational emergence of scale-free networks that could cooperate to maximize the integrated sustainability among them
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