Tree of the sea: The use of the internal growth lines in the shell of Arctica islandica (Bivalvia, Mollusca) for the retrospective assessment of marine environmental change

Rob Witbaard

    Research output: ThesisThesis fully internal (DIV)

    1636 Downloads (Pure)


    Within the North Sea the southernmost distribution limit of Arctica follows the 30 m depth contour. This border is most likely set by the maximum bottom water temperature of 16 graden. Densities of 16 individuals/m2 were found in the northern North Sea. In the south-eastern North Sea the maximum density of 0.1 ind./m2 is low, especially compared to those around Iceland or the western Atlantic. In the south-eastern North Sea the densities decreased between the 1970s and the early 1990s. Both the percentage of sampling stations and the corresponding densities decreased. The mortality rate in the south-eastern North Sea is twice as high as that in the northern North Sea. ... Zie: Summary
    Original languageEnglish
    QualificationDoctor of Philosophy
    Awarding Institution
    • University of Groningen
    • Wilde, P, Supervisor
    Award date30-May-1997
    Publication statusPublished - 1997


    • Proefschriften (vorm)
    • Ecologische aspecten
    • Groei
    • Bivalvia
    • 42.73

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