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Gaillimh, Ireland

Staunton J.,Applied Ecology Unit | Williams C.D.,Biocontrol | Mc Donnell R.J.,University of California at Riverside | Fleming G.T.A.,Microbiology | And 2 more authors.
Applied Ecology and Environmental Research

Although wetlands are of ecological and economic importance, they continue to be lost to anthropogenic activities such as infilling. The impacts of wetland infilling with construction and demolition (C&D) waste on wetland plant and dipteran (Insecta: Diptera) communities were examined. Areas of wetland infilled with C&D waste compared to non-infilled areas had: a) higher soil pH and lower soil moisture/organic content b) a relatively higher percentage of ruderal plant communities c) relatively fewer dipteran families that were wetland specialist, gall-forming, parasitic and haematophagous d) relatively lower abundances and species richness of marsh flies (Diptera: Sciomyzidae). Challenges encountered during this study included locating C&D waste sites obtaining permission from landowners to undertake this study frequent damage and theft of equipment due to human interference, machinery and infilling activity. Given the current paucity of data regarding the ecological impacts of infilling with C&D waste on wetlands and the considerable challenges with undertaking such studies, we make recommendations for appropriate site selection and monitoring at C&D waste infill sites. © 2014, ALÖKI Kft. Source

Staunton J.,Applied Ecology Unit | Williams C.D.,Biocontrol | Morrison L.,Earth and Ocean science and Ryan Institute | Henry T.,Earth and Ocean Science | And 2 more authors.
Land Use Policy

Although infilling of wetlands (legal and illegal) is commonplace, little is known about the spatio-temporal distribution of construction & demolition (C&D) waste infill sites at a local scale. This is of particular concern given the multiple functions of wetlands including, inter alia, habitat provision, flood control and water storage. This case study from an Irish local authority quantifies, for the first time, the use of wetland habitats for C&D waste infilling in addition to identifying patterns of C&D waste site distribution and recording issues of non-compliance. We found that C&D waste cover on study sites grew from an estimated <10. ha in 1995 to >200. ha in 2010 within which time rapid economic growth occurred. Wet grasslands and peatlands were the most commonly infilled habitats, particularly near urban areas and adjacent to major roads. Of greater concern was that over 40% of C&D waste sites granted permits were located within one kilometre of Special Areas of Conservation (EU Habitats Directive) and 54% were located on extremely vulnerable aquifers. Conditions attached to infilling permits were frequently broken and commonly occurring illegal infilling sites had similar distribution patterns to the legal sites. Providing local authorities with sufficient resources to effectively police these sites in combination with examining alternative uses for C&D waste (e.g. recycling), are likely to be the most effective ways of dealing with these issues. More rigorous ecological investigations of proposed infilling sites prior to granting of permits would also limit the number of wetlands affected by infilling. © 2015 Elsevier Ltd. Source

Bowers D.G.,Bangor University | Roberts E.M.,Bangor University | White M.,Earth and Ocean Science | Moate B.D.,National Oceanography Center
Continental Shelf Research

Observations of coloured dissolved organic matter (CDOM) and salinity have been used to identify water types and mixing in the Irish Sea. Three principal water types are identified: (1) Celtic Sea water, of high salinity and low CDOM which enters the Irish Sea from the south; (2) English coastal water, of low salinity and intermediate CDOM which is introduced into the eastern Irish Sea through rivers and (3) Irish Coastal water, with intermediate salinity and high CDOM. A mixing triangle is used to determine the geographical distribution of these three water types. This shows that the Celtic Sea water flowing northwards mixes initially with Irish water and later with English coastal water so that the mixture leaving the Irish Sea through the North Channel comprises 66% Celtic Sea water, 14% Irish water and 20% English water. We estimate the lateral mixing coefficient to be 67m2s-1. The CDOM absorption coefficient at 440nm in the water leaving the Irish Sea is 0.17m-1. Converting this to an estimate of the dissolved organic carbon concentration and multiplying by the volume transport in the North Channel, the net flux of dissolved organic carbon leaving the Irish Sea through the North Channel is calculated to be between 1 and 2TgCyear-1. © 2013 Elsevier Ltd. Source

Mohn C.,University of Aarhus | Rengstorf A.,Earth and Ocean Science | White M.,Earth and Ocean Science | Duineveld G.,Netherlands Institute for Sea Research | And 3 more authors.
Progress in Oceanography

Observations from numerous cold-water coral locations in the NE Atlantic show energetic near-bottom flow dynamics along the European continental margin at individual coral mounds and mound clusters. Dynamics are largely controlled by tide-topography interaction generating and enhancing periodic motions such as trapped waves, freely propagating internal tides and internal hydraulic jumps. In this study, linkages between key abiotic parameters and cold water coral occurrences are explored across entire cold-water coral mound provinces using an integrated modelling and observational approach. The 3-D ocean circulation model ROMS-AGRIF was applied to simulate near-bottom hydrodynamic conditions at three provinces in the NE Atlantic (Logachev mounds, Arc mounds and Belgica mounds) adopting a nested model setup with a central grid resolution of 250. m. Simulations were carried out with a focus on accurate high-resolution topography and tidal forcing. The central model bathymetry was taken from high-resolution INSS (Irish National Seabed Survey) seafloor mapping data. The model was integrated over a full one-year reference period starting from the 1st January 2010. Interannual variability was not considered. Tidal forcing was obtained from a global solution of the Oregon State University (OSU) inverse tidal model. Modelled fields of benthic currents were validated against available independent in situ observations. Coral assemblage patterns (presence and absence locations) were obtained from benthic surveys of the EU FP7 CoralFISH programme and supplemented by data from additional field surveys. Modelled near-bottom currents, temperature and salinity were analysed for a 1-month subset (15th April to 15th May 2010) corresponding to the main CoralFISH survey period. The model results show intensified near-bottom currents in areas where living corals are observed by contrast with coral absence and random background locations. Instantaneous and time-mean current speeds at mound clusters in the Logachev province exceeded typical values in non-coral areas by up to a factor of three. Currents at cold-water coral locations in the Arc and Belgica mound provinces were less energetic, but still elevated compared to non-coral locations. An analysis of dynamical processes associated with oscillatory flow interacting with topography suggests that these motions are locally important food supply mechanisms to cold-water corals by promoting large amplitude local vertical mixing and organic matter fluxes. It is shown that their presence varies considerably between provinces based on the interplay of topographic slope, flow magnitude and ambient stratification. © 2013 Elsevier Ltd. Source

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