IMPACTS OF OFFSHORE WIND FARMS ON DIVERSITY OF DEMERSAL ASSEMBLAGES ON SANDBANKS OF THE WESTERN IRISH SEA

Transcript

1. IMPACTS OF OFFSHORE WIND FARMS ON
   DIVERSITY OF DEMERSAL ASSEMBLAGES
   ON SANDBANKS OF THE WESTERN IRISH
   SEA
   Javier Atalah; Julien Chopelet; Ilaria Coscia;
   Jennifer Coughlan;
   Edward Farrell; Jayne Fitch*
   MARine Biodiversity, Ecology and Evolution
   University College Dublin
   Gemma Byrne
   Geological Services Ireland
   MARBEE
   

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2. Background
   • Europe wide carbon mitigation agreed under
   Kyoto protocol.
   • Renewable energy is a growing market.
   • Arklow Bank presently only offshore wind farm
   in Ireland, currently 7 turbines with plans to
   increase to 200.
   

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3. Introduction
   • Sandbanks are important habitats,
   proposed Special Area of Conservation
   candidates.
   • Due to potential impacts through wind
   farms there is a need to have a
   comprehensive understanding of marine
   biodiversity.
   

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4. Potential Impacts
   • Bird migration.
   • Cetaceans.
   • Artificial reef effect.
   • Alter of hydrodynamics.
   • Scouring and sedimentation.
   • Electromagnetic fields.
   

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5. Aims
   1. Characterise and compare community
   structure and biodiversity of benthic and
   demersal assemblages in sandbanks of
   the Western Irish Sea.
   2. Assess potential impacts of offshore wind
   farms and cable route on biodiversity of
   benthic and demersal assemblages.
   

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7. Study
   Sites
   

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8. Statistical analyses
   • Analysis of variance (ANOVA) performed
   on Species Richness, Total Abundance
   and Shannon-Weiner Diversity Index.
   • Community structure was visualized using
   non-metric Multi Dimensional Scaling.
   • Community Structure as a whole were
   compared using Permanova.
   • PRIMER 6 + PERMANOVA
   

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9. Results
   Only non-encrusting organisms were
   included in analysis, of these we
   identified 14,295 individuals in 98
   taxa, in 5 Phyla.
   0.74%
   18.68%
   5.53%
   62.90%
   12.14%
   Annelida
   Crustacea
   Mollusca
   Echinodermata
   Chordata
   

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10. Species Richness
    Banks : p > 0.05
    I vs C: p > 0.05
    0
    25
    50
    Kish Arklow Cable Blackwater
    Species richness +/- 1 SE
    

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11. Total Abundance
    Banks : p > 0.05
    I vs C: p > 0.05
    0
    6
    12
    Kish Arklow Cable Blackwater
    Log (Total abundance) +/- 1 SE
    

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12. Shannon –Weiner Diversity Index
    Banks : p >0.05
    I vs C: p = 0.0108
    0
    1
    2
    3
    4
    Kish Arklow Cable Blackwater
    Shannon +/- 1 SE
    

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13. Community structure
    PERMANOVA
    I vs C: p > 0.05
    Banks : p= 0.006
    

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14. Characteristic Taxa
    Kish Arklow Cable Blackwater
    

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15. Summary
    • The existing wind turbines and associated cable
    did not alter the abundance, species richness
    and structure of the demersal and benthic
    communities sampled.
    • There was an increase in Shannon-Weiner
    diversity at the cable site compared to the
    control.
    • At the spatial and temporal scale examined
    here, offshore wind farms were found to have
    little impact on fauna in this naturally highly
    disturbed environment.
    

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16. Discussion
    • Close monitoring during future
    construction and operation of the
    proposed large scale installation is
    essential to identify any future impacts.
    • Conservation opportunities may exist to
    create marine reserves around offshore
    wind farms by introducing exclusion/no
    take zones.
    

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17. Acknowledgements
    • Marine Institute for funding the research
    • Crew of the RV Celtic Voyager
    • Tasman Crowe and Stefano Mariani- UCD
    • Mathieu Cusson- University of Pisa
    • Cormac Nolan- UCD
    • Brendan O’Connor- BEC
    • Chris Frid- University of Liverpool
    • Jim Wilson- TCD
    • Brian O’Doherty- Airtricty and Alexis Billet- GE Energy
    References available upon request.
    

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