Publication Date:
2022-05-25
Description:
Author Posting. © Elsevier B.V., 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine Pollution Bulletin 59 (2009): 193-206, doi:10.1016/j.marpolbul.2009.02.022.
Description:
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
the 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.
Description:
We gratefully acknowledge past financial support from Norsk Hydro, and continuing
financial support from StatoilHydro, the Norwegian Research Council, and the Howard
Hughes Medical Institute through Bates College. This publication was made possible, in part, by NIH Grant Number P20 RR-016463 from the INBRE Program of the National Center for Research Resources.
Keywords:
Arctic
;
Barents Sea
;
Benthic community
;
Bivalve growth
;
Climate oscillation
;
Environmental forcing
;
North Atlantic Oscillation
;
White Sea
;
Sclerochronology
;
Serripes groenlandicus
;
Shell geochemistry
;
Stable isotopes
;
Trace element ratios
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
Format:
application/pdf
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