Skip to content. | Skip to navigation

Laboratoire d’Etudes en Géophysique et Océanographie Spatiales

Personal tools

This is SunRain Plone Theme


You are here: Home / Research teams / TIM / Projects / BONUS/GOODHOPE

BONUS - GOODHOPE: Biogeochemical cycles and dissolved/particle interactions in the Southern ocean, studied with neodymium and iron isotopes and REE

by TIM last modified Nov 20, 2020 10:33 AM


 See also BGH web site.  



Scientific Rationale

The oceanic area located South of South Africa is important in various respects:
- It is a critical crossroad for the global thermohaline circulation as it provides an inter-ocean communication route for heat and freshwater anomalies (Sloyan & Rintoul, 2001), and for chemical elements, notably through Mesoscale transports.
- As a part of the Southern Ocean, it is also a key area for the global carbon cycle. The outcropping of deep water masses allows for the exchange of gases such as CO2 between the deep sea and the atmosphere, while the incomplete utilization of nutrients by marine phytoplankton allows the concentration of CO2 in the atmosphere to be substantially greater than would be the case if these nutrients were used efficiently.
- Transport processes in this area could transfer significant amount of terrigeneous matter form the African area southwards into the Antarctic Circumpolar Current.
The scarcity of direct observations has greatly hampered our understanding of this physical, biological and chemical environment.



Bonus/GoodHope is a multidisciplinary project, coupling physics, chemistry and biology. It is mainly based on a cruise, carried out on board the R/V Marion Dufresne in February March 2008 (Fig. 1). The project, led by LPO and LEMAR (Brest) involves a large number of investigators, from 16 laboratories, from 6 countries. It also includes a modelling task.

The chemical composition of many elements have been measured in the suspended particles notably, Al, Ca, Mn, Fe, Co, Ni, Cu, Sr, Cd, Ba, REE, Th. These kind of data are very rare for most of these elements. They provide diverse information (micronuient cyclings, dissolved particles interactions, land to ocean fluxes etc…). Some have been published (Fe, Co, REE, Ba, Th [Bown et al., 2011; Garcia-Solsona et al., 2014]) other remain to be published. A work on 230Th is under progress in collaboration with LSCE.


F. Lacan, C. Jeandel, C. Pradoux, C. Abadie, E. Garcia-Solsona, M. Labatut, A. Radic





Peer review articles related to this project:

Lacan, F., Radic, A., Jeandel, C., Poitrasson, F., Sarthou, G., Pradoux, C., Freydier, R., 2008. Measurement of the isotopic composition of dissolved iron in the open ocean. Geophysical Research Letters 35.
Bown, J., Boye, M., Baker, A., Duvieilbourg, E., Lacan, F., Le Moigne, F., Planchon, F., Speich, S., Nelson, D.M., 2011. The biogeochemical cycle of dissolved cobalt in the Atlantic and the Southern Ocean south off the coast of South Africa. Marine Chemistry 126, 193–206.
Garcia-Solsona, E., Jeandel, C., Labatut, M., Lacan, F., Vance, D., Chavagnac, V., Pradoux, C., 2014. Rare earth elements and Nd isotopes tracing water mass mixing and particle-seawater interactions in the SE Atlantic. Geochimica et Cosmochimica Acta 125, 351–372.
Conway, T.M., John, S.G., Lacan, F., 2016. Intercomparison of dissolved iron isotope profiles from reoccupation of three GEOTRACES stations in the Atlantic Ocean. Marine Chemistry 183, 50–61.
Abadie, C., Lacan, F., Radic, A., Pradoux, C., Poitrasson, F., 2017. Iron isotopes reveal distinct dissolved iron sources and pathways in the intermediate versus deep Southern Ocean. PNAS 114, 858–863.

Document Actions