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Carbon export in contrasting environments in the SE Pacific: a dual approach using drifting traps and 238 U: 234 Th disequilibria. Juan Carlos Miquel & Beat Gasser IAEA Marine Environment Laboratory Monaco. Figure 1 : Location of stations and transect during the BIOSOPE cruise
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Carbon export in contrasting environments in the SE Pacific: a dual approach using drifting traps and 238U:234Th disequilibria Juan Carlos Miquel & Beat Gasser IAEA Marine Environment Laboratory Monaco
Figure 1 : Location of stations and transect during the BIOSOPE cruise short stations (6 hours) long stations at a fixed location (~ 3 days) studies of specific sites (~ 6 jours)
Trap sampling: 9 stations 3 sta:48,24,48 hrs 3 days 3 days 3 days 3 sta:48,24,48 hrs Figure 1 : Location of stations and transect during the BIOSOPE cruise short stations (6 hours) long stations at a fixed location (~ 3 days) studies of specific sites (~ 6 jours)
Trap sampling • Drifting array • Two depth: 150, 300 m • Samples preserved: formaldehyde • Trap model: Technicap PPS3/PPS5 • Time resolution: 24 hrs Analysis • Th-234, counting • C/N, C.org, C.inorg • Pigments HPLC (LOV) • Lipid biomarkers • Opal (COM)
If: Flux PPS3 PPS5 (mg m-2 d-1) (mg d-1) (mg d-1) 5-10 0.75-1.25 5-10 100-200 12.5-25 100-200 • 62.5 500
SAP sampling: 9 profiles Figure 1 : Location of stations and transect during the BIOSOPE cruise short stations (6 hours) long stations at a fixed location (~ 3 days) studies of specific sites (~ 6 jours)
particles > 70 m particles > 0.7 m dissolved, cartridges A & B
238U (4.49 109 y) 234U (2.48 105 y) 234Pa (1.18 mn) 234Th (24.1 d) 230Th (8.0 104 y) 226Ra (1622 y) Uranium-238 natural decay series
y = 28.2 x r2 = 0.60
SAP profiles • One hour pumping (min.) • 600-900 l • 10 depths: 2, (25), 50, 75, 100, 125, 150, (175), 200, 300 m • Steady-state modelling Analysis >70 m particles • Th-234, counting • C.org 0.7-70 m particles • Th-234, counting • C/N, C.org, C.inorg • Pigments HPLC (LOV) • Lipid biomarkers at 3 depths: 50, 100, 300 m (and/or max. Chl.a) dissolved • Th-234, counting (sampling for U-238)