Off Congo waters (Angola Basin, Atlantic Ocean): A hot spot for cadmium-phosphate fractionation - Université de Bretagne Occidentale
Journal Articles Limnology and Oceanography Year : 2013

Off Congo waters (Angola Basin, Atlantic Ocean): A hot spot for cadmium-phosphate fractionation

Abstract

We report the distribution of cadmium at 13 stations along 5.83°S in the Angola Basin. The studied area (which is influenced by the plume of the Congo River, doming, and relatively high primary production) is characterized by relatively low-circulation regime, which results in a strong oxygen minimum. In subsurface, very low cadmium : phosphate (Cd : P) ratios (0.05-0.10 nmol L−1 : µmol L−1) were observed below the euphotic zone (depth range = 50-200 m), indicating that mineralization is the main process explaining the Cd-P fractionation. Cd-P decoupling is not restricted to subsurface waters, but occurs also throughout the oxygen minimum zone. An isopycnal analysis of the Cd : P ratio throughout the Atlantic Ocean shows that upper and intermediate waters in the South-east Atlantic are highly altered in terms of Cd-P properties. Benthic inputs at 4000 m were associated with degradation of organic matter with an important siliceous component, but were not accompanied by substantial changes in the Cd : P ratio.
No file

Dates and versions

hal-00845404 , version 1 (17-07-2013)

Identifiers

Cite

Matthieu Waeles, Jean-François Maguer, François Baurand, Ricardo D. Riso. Off Congo waters (Angola Basin, Atlantic Ocean): A hot spot for cadmium-phosphate fractionation. Limnology and Oceanography, 2013, 58 (4), pp.1481-1490. ⟨10.4319/lo.2013.58.4.1481⟩. ⟨hal-00845404⟩
108 View
0 Download

Altmetric

Share

More