The linear relationship between the seawater cadmium and phosphate dissolved concentrations lead to use the cadmium/calcium (Cd/Ca) imprinted in calcareous archives to reconstruct the past phosphate (PO4) distributions. However, variations in the Cd/PO4 ratio between different water masses and within vertical oceanic profiles were recently identified. Among the processes that could explain these variations, sequestration […]
Jan / 07 / 2019
Bourne and co-workers examine the particulate cadmium to phosphorus ratio (Cd/P) variations of 3 particle fractions (<1µm, 1-51µm and >51µm) from 50 casts covering spatial and temporal scales never reached so far for these parameters. This impressive data set allows them to study the effects of an El Niño, upwelling, large-scale in situ Fe fertilization, low-oxygen conditions, […]
Nov / 01 / 2018
Yang et al. (2018, see reference below) studied the relative importance of physical and biogeochemical processes on controlling the isotopic composition of dissolved and particulate cadmium (Cd) in a GP18 transect, crossing over the relatively cold and eutrophic Oyashio Extension region and the relatively warm and oligotrophic Kuroshio Extension region. Particulate samples revealed preferential uptake […]
Jul / 18 / 2018
Xie and co-workers (2017, see reference below) report cadmium (Cd) isotopic compositions from five stations and 15 tow-Fish surface waters from 50ºS to the equator along GEOTRACES GA02 Leg 3. Along this transect, the coupled Cd concentrations and Cd isotopes reflect classical behaviour dominated by preferential uptake of light Cd by the biological species at […]
Jun / 01 / 2017
Xie and co-authors (2015, see reference below) report vertical profiles of dissolved cadmium (Cd) in the western South Atlantic Ocean (GEOTRACES section GA02), which show nutrient-like distributions similar to those of the macronutrient phosphate (PO4). A close look at the data reveal: In the surface ocean, preferential uptake of Cd over PO4 by phytoplankton occurs […]
Jan / 25 / 2016
The well-established strong linear relationship linking dissolved cadmium (Cd) and phosphorus (P) concentrations in seawater is at the origin of the attraction of Cd as a proxy for PO4 in the paleocean. However, exploring the dissolved Cd and PO4 distributions in the ocean, Quay and co-workers (2015, see reference below) show that the Cd/P of […]
Sep / 21 / 2015
Cadmium (Cd) is a micronutrient for marine algae and has a marine distribution similar to the macronutrients nitrate and phosphate. The use of sedimentary microfossil records of Cd, thus, allow reconstructions of past ocean nutrient distributions that facilitate the understanding of the role of the oceans in the carbon cycle and climate change. However, this […]
Jun / 11 / 2014
The first simultaneous method for the determination of these three isotope systems in seawater has been published. This method is designed for use on only a single litre of seawater representing a 1–20 fold reduction in sample size and a 4–130 decrease in blank compared to previously reported methods. The procedure yields data with high […]
Sep / 03 / 2013
For the first time detailed mercury (Hg) speciation was determined along an Australia-Antarctic section (Cossa, et al., 2011) and cadmium (Cd) isotopes along a South Africa-Antarctic section (Abouchami W., et al., 2011). Both were acquired along two IPY-GEOTRACES sections: SR3 CASO-GEOTRACES (GIPY6) and ZERO&DRAKE (GIPY5) respectively. Hg species distribution suggests distinct features in the Southern […]
Apr / 11 / 2012