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The Scottish Association for Marine Science is one of Europe's leading marine science research organisations and one of the oldest oceanographic organisations in the world. Sited beside Dunstaffnage Castle, in Argyll, Scotland, the institute carries out advanced research in the marine environment, including polar research in the Arctic and Antarctic. Wikipedia.


Jones B.L.,Scottish Association for Marine Science | Kerrigan E.C.,Imperial College London
Automatica | Year: 2010

This paper describes a new and straightforward method for controlling spatially distributed plants based on low-order models obtained from spatial discretization techniques. A suitable level of discretization is determined by computing the sequence of ν-gaps between weighted models of successively finer spatial resolution, and bounding this by another sequence with an analytic series. It is proved that such a series forms an upper bound on the ν-gap between a weighted model in the initial sequence and the spatially distributed weighted plant. This enables the synthesis, on low-order models, of robust controllers that are guaranteed to stabilize the actual plant, a feature not shared by most model reduction methods where the gap between the high-order model and plant is often not known, and where the gap between high-order and reduced models may be too expensive to compute. Since the calculation of the current bound is based on weighted models of small state-dimension, the new method avoids the numerical problems inherent in large-scale model reduction based approaches. The ideas presented in this paper are demonstrated on a disturbance rejection problem for a 1D heat equation. © 2010 Elsevier Ltd. All rights reserved. Source


Hughes D.J.,Scottish Association for Marine Science
Marine Ecology Progress Series | Year: 2011

In the British Isles, aggregations of the tubicolous polychaete Serpula vermicularis L. occur only in a few localities in western Scotland and Ireland. In Loch Creran, Argyll, where written observations extend back to the 1880s, build-ups of skeletal debris constituting a true reef framework are notably absent. To investigate the taphonomic processes affecting the residence time of relict tube material, cleaned and weighed skeletal fragments were deployed on panels amongst living worm aggregations. Fragments were either open to the environment or enclosed in mesh cylinders to exclude grazing urchins. Panels were recovered and fragments re-weighed after 1, 2, 3 and 5 yr in situ. Caged fragments typically increased in dry weight over time, while most open fragments remained at steady-state or showed small weight decreases. Change in weight was correlated with the number of living tubeworms which had settled onto the skeletal fragments. Open fragments showed no consistent temporal trend in weight change, suggesting that urchin grazing was not a major bioerosive process over the 5 yr experimental timescale. Data from another locality where serpulid aggregations suffered mass mortality between 1984 and 1994 show that tube debris can persist for at least 15 yr in sea loch environments. S. vermicularis aggregations in sea lochs may be relatively transient features, appearing and disappearing over decadal timescales. © Inter-Research 2011. Source


Potts T.,Scottish Association for Marine Science
Journal of Cleaner Production | Year: 2010

The combined impacts of the financial crisis and climate change are driving the evolution of sustainable business and changing the way that governments plan for development. Markets are emerging for a range of environmentally orientated products and services as societies move (or lurch) towards reducing impacts and adapt to changing conditions. National governments are actively formulating policy and providing investment to develop green economies as one of the responses to the global financial crisis. Many of the political and economic drivers have been focused at the international and national scale, and while critical for setting the national framework for development, it often neglects the key role that regions and localities can play in ecological modernization. This paper explores two regional case studies in New South Wales (NSW), Australia, that are initiating shifts towards networks of sustainable businesses and communities and offers recommendations for further policy development. The focus of this paper is on the evolving regional sustainability market and its relationship to other social institutions including governments, communities and the individual. The unifying concept is the idea of the 'natural advantage', a model that integrates innovation and sustainability as a part of the regional development policy agenda. © 2010 Elsevier Ltd. All rights reserved. Source


Burrows M.T.,Scottish Association for Marine Science
Marine Ecology Progress Series | Year: 2012

Community assemblages on subtidal rock change markedly along gradients of wave energy, tidal flow, and turbidity. The importance of these assemblages for rare and delicate species, for shellfish, as nursery areas for fish, and for their contribution to ecosystem functioning in coastal areas has prompted much conservation effort in many countries. I applied a rapid method of calculating a large high-resolution (200 m scale) map of wave exposure <5 km from the UK coastline to compare with UK subtidal biodiversity records from diver surveys from the 1970s to the 2000s. Satellite-derived estimates of ocean colour, and tidal flows from hydrodynamic models were also extracted for each site. Ordinal logistic regression of categorical abundance data gave species-distribution patterns with wave fetch and depth and dependence on chlorophyll and tidal flows: macroalgae declined with increasing chlorophyll and increased with tidal flow. Multivariate community analysis showed shifts from algae to suspension-feeding animals with increasing depth and in areas of high chlorophyll and tidal flow and a change from delicate forms in waveshelter to robust species at wave-exposed sites. The strongest positive influence on species diversity was found to be the presence of the kelp Laminaria hyperborea: sites with 0% cover had a median of 6 species, while those with >40% cover had a median of 22 species. Laminaria hyperborea, and the most diverse communities, is found in areas of estimated low chlorophyll concentrations and in the most wave-exposed environments, which are often but not always in areas of high tidal flow. © Inter-Research 2012. Source


Wilding T.A.,Scottish Association for Marine Science
PLoS ONE | Year: 2012

Aquaculture is growing rapidly in response to an increasing demand for protein and the over-exploitation of wild fisheries. Mussel (family Mytilidae) production has doubled over the last decade and currently stands at 1.5 million tonnes production per annum. Mussels produce organic biodeposits which are dispersed around the production site and, potentially, impact the receiving environment in a number of inter-linked ways. The reported benthic impacts that occur, primarily through the accumulation of these biodeposits and associated organic enrichment, vary widely between studies. The objectives of this research were to determine the nature of the relationship between sediment redox (a proxy for oxygenation) and farm-proximity and covariables whilst accounting for, and quantifying, differences in redox between sites. Sediment cores (N = 159) were taken remotely around a random sample of mussel farms, redox was measured at 10 mm sediment depth and linked to farm-distance and sediment organic/shell content and particle size, using an additive, mixed, weighted regression model. Redox varied considerably between sites and there was a highly significant reduction (50 mV) in redox adjacent to the mussel lines. Redox increased non-linearly with distance, rising rapidly at >7 m from the farm edge. The modest reduction in sediment oxygenation in close proximity to mussel farms reported here suggests that farms located over sediments characterised by pre-existing oxygen stress are likely to exacerbate benthic species impoverishment associated with reducing sedimentary conditions whilst those located over highly oxygenated sediments are likely to increase benthic productivity. © 2012 Thomas A. Source

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