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| Venchiarutti, C.; Roy-barman, M.; Freydier, R.; Van Beek, P.; Souhaut, M.; Jeandel, C.. |
| Dissolved and particulate excess (230)Th and (231)Pa concentrations (noted (230)Th(xs) and (231)Pa(xs) respectively) and (231)Pa(xs)/(230)Th(xs) activity ratios were investigated on and out of the Kerguelen plateau (Southern Ocean) in the framework of the Kerguelen Ocean and Plateau compared Study project in order to better understand the influence of particle flux and particle chemistry and advection on the scavenging of (231)Pa. In the wake of Kerguelen, particulate (231)Pa(xs) is relatively abundant compared to its content in the dissolved phase. This, together with the low fractionation observed between (230)Th and (231)Pa (F(Th/Pa) ranging from 0.06 +/- 0.01 to 1.6 +/- 0.2) reflects the domination of the biogenic silica in the particle pool. Along the... |
| Tipo: Text |
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| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00228/33894/32272.pdf |
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| Sanial, V.; Van Beek, P.; Lansard, B.; Souhaut, M.; Kestenare, E.; D'Ovidio, F.; Zhou, M.; Blain, S.. |
| The Southern Ocean is known to be the largest high-nutrient, low-chlorophyll (HNLC) region of the global ocean due to iron limitation. However, a large phytoplankton bloom develops annually downstream of the Kerguelen Islands, a bloom which is sustained partly by iron released from the sediments deposited onto the shelves. In the framework of the KEOPS-2 project, we used radium isotopes (Ra-224, T-1/2 = 3.66 d; Ra-223, T-1/2 = 11.4 d; Ra-228, T-1/2 = 5.75 yr) to provide information on the origin of iron fertilization and on the timescales of the transfer of sedimentderived inputs (including iron and other micronutrients) towards offshore waters. Significant Ra-224 and Ra-223 activities were found in the near vicinity of the Kerguelen Islands, in agreement... |
| Tipo: Text |
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| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00291/40256/39575.pdf |
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