Record number :
1981156
Title of article :
Bivalves as indicators of environmental variation and potential anthropogenic impacts in the southern Barents Sea
Author/Authors :
Carroll، نويسنده , , Michael L. Catalano-Johnson، نويسنده , , Beverly J. and Henkes، نويسنده , , Gregory A. and McMahon، نويسنده , , Kelton W. and Voronkov، نويسنده , , Andrey and Ambrose Jr.، نويسنده , , William G. and Denisenko، نويسنده , , Stanislav G.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2009
Pages :
14
From page :
193
To page :
206
Abstract :
Identifying patterns and drivers of natural variability in populations is necessary to gauge potential effects of climatic change and the expected increases in commercial activities in the Arctic on communities and ecosystems. We analyzed growth rates and shell geochemistry of the circumpolar Greenland smooth cockle, Serripes groenlandicus, from the southern Barents Sea over almost 70 years between 1882 and 1968. The datasets were calibrated via annually-deposited growth lines, and growth, stable isotope (δ18O, δ13C), and trace elemental (Mg, Sr, Ba, Mn) patterns were linked to environmental variations on weekly to decadal scales. Standardized growth indices revealed an oscillatory growth pattern with a multi-year periodicity, which was inversely related to the North Atlantic Oscillation Index (NAO), and positively related to local river discharge. Up to 60% of the annual variability in Ba/Ca could be explained by variations in river discharge at the site closest to the rivers, but the relationship disappeared at a more distant location. Patterns of δ18O, δ13C, and Sr/Ca together provide evidence that bivalve growth ceases at elevated temperatures during the fall and recommences at the coldest temperatures in the early spring, with the implication that food, rather than temperature, is the primary driver of bivalve growth. The multi-proxy approach of combining the annually integrated information from the growth results and higher resolution geochemical results yielded a robust interpretation of biophysical coupling in the region over temporal and spatial scales. We thus demonstrate that sclerochronological proxies can be useful retrospective analytical tools for establishing a baseline of ecosystem variability in assessing potential combined impacts of climatic change and increasing commercial activities on Arctic communities.
Keywords :
Trace element ratios , Arctic , Barents Sea , Climate oscillation , sclerochronology , Shell geochemistry , stable isotopes , Bivalve growth , benthic community , White Sea , Serripes groenlandicus , North Atlantic Oscillation , Environmental forcing
Journal title :
Marine Pollution Bulletin
Serial Year :
2009
Link To Document :
بازگشت