Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 3.480
IF3.480
IF 5-year value: 4.194
IF 5-year
4.194
CiteScore value: 6.7
CiteScore
6.7
SNIP value: 1.143
SNIP1.143
IPP value: 3.65
IPP3.65
SJR value: 1.761
SJR1.761
Scimago H <br class='widget-line-break'>index value: 118
Scimago H
index
118
h5-index value: 60
h5-index60
Volume 9, issue 3
Biogeosciences, 9, 1183–1194, 2012
https://doi.org/10.5194/bg-9-1183-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
Biogeosciences, 9, 1183–1194, 2012
https://doi.org/10.5194/bg-9-1183-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 28 Mar 2012

Research article | 28 Mar 2012

Coupled CO2 and O2-driven compromises to marine life in summer along the Chilean sector of the Humboldt Current System

E. Mayol1,2, S. Ruiz-Halpern2, C. M. Duarte1,3, J. C. Castilla1,4, and J. L. Pelegrí5,1 E. Mayol et al.
  • 1Laboratorio Internacional de Cambio Global, CSIC-PUC, Facultad de Ciencias Biológicas, Edificio No. 210, Of. 425, Pontificia Universidad Católica de Chile, Avenida Bernardo O'Higgins 340 ó Portugal 49, Santiago, Casilla 114-D, Chile
  • 2Instituto Mediterráneo de Estudios Avanzados, CSIC-UIB, Miquel Marqués 21, 07190 Esporles, Mallorca, Spain
  • 3The UWA Oceans Institute, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
  • 4Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Almadea 340, Santiago, Chile
  • 5Institut de Ciències del Mar, CSIC, Barcelona, Spain

Abstract. Carbon dioxide and coupled CO2 and O2-driven compromises to marine life were examined along the Chilean sector of the Humboldt Current System, a particularly vulnerable hypoxic and upwelling area, applying the Respiration index (RI = log10 pO2pCO2) and the pH-dependent aragonite saturation (Ω) to delineate the water masses where aerobic and calcifying organisms are stressed. As expected, there was a strong negative relationship between oxygen concentration and pH or pCO2 in the studied area, with the subsurface hypoxic Equatorial Subsurface Waters extending from 100 m to about 300 m depth and supporting elevated pCO2 values. The lowest RI values, associated to aerobic stress, were found at about 200 m depth and decreased towards the Equator. Increased pCO2 in the hypoxic water layer reduced the RI values by as much as 0.59 RI units, with the thickness of the upper water layer that presents conditions suitable for aerobic life (RI>0.7) declining by half between 42° S and 28° S. The intermediate waters hardly reached those stations closer to the equator so that the increased pCO2 lowered pH and the saturation of aragonite. A significant fraction of the water column along the Chilean sector of the Humboldt Current System suffers from CO2–driven compromises to biota, including waters corrosive to calcifying organisms, stress to aerobic organisms or both. The habitat free of CO2-driven stresses was restricted to the upper mixed layer and to small water parcels at about 1000 m depth. Overall pCO2 acts as a hinge connecting respiratory and calcification challenges expected to increase in the future, resulting in a spread of the challenges to aerobic organisms.

Publications Copernicus
Download
Citation
Altmetrics
Final-revised paper
Preprint