Publication Date:
2017-12-13
Description:
Naturally acidified environments, such as CO2
vents, are important sites to evaluate the potential effects
of increased ocean acidification on marine ecosystems and
biota. Here we assessed the effect of high CO2/
low pH on
otolith shape and chemical composition of six coastal fish
species (Chromis chromis, Coris julis, Diplodus vulgaris,
Gobius bucchichi, Sarpa salpa, Symphodus ocellatus) in a
Mediterranean shallow CO2
vent. Taking into consideration
the major and trace elements found near the vent and the
gradient of dissolved inorganic carbon, we compared the
otolith chemical signatures of fish exposed long-term to elevated
CO2
emissions and reduced pH (mean pH 7.8) against
fish living in two control sites (mean pH 8.2). A number of
element:Ca ratios (Na:Ca, Mg:Ca, Mn:Ca, Cu:Ca, Zn:Ca,
Sr:Ca, Ba:Ca and Pb:Ca), along with isotope ratios, were
measured in otoliths (δ13C and δ18O) and water (δ13CDIC)
samples. Additionally, we performed otolith outline shape and morphometric analysis to evaluate the effect of high
CO2/
low pH. We observed species-specific responses with
regards to both shape and chemical signatures. Significant
differences among sites were found in otolith shape (elliptical
Fourier descriptors) of G. bucchichi and D. vulgaris.
Elemental and isotopic signatures were also significantly
different in these site attached species, though not for the
other four. Overall, the carbon isotopic composition seems
a good proxy to follow pH gradient in naturally acidified
area. Ultimately, besides improving our knowledge of the
effects of high CO2/
low pH on otoliths, the present results
contribute to our understanding on their use as natural tags.
Description:
Published
Description:
191
Description:
4A. Oceanografia e clima
Description:
JCR Journal
Keywords:
fish otolith shape
;
submarine high PCO2 vents
;
Otolith Carbon isotope composition
;
Otolith chemical composition
;
03.04. Chemical and biological
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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