juan carlos miquel & beat gasser iaea marine environment laboratory monaco
DESCRIPTION
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 - PowerPoint PPT PresentationTRANSCRIPT
Carbon export in contrasting environments in the SE Pacific: a dual approach using drifting
traps and 238U:234Th disequilibria
Juan Carlos Miquel & Beat GasserIAEA Marine Environment LaboratoryMonaco
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)
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 days 3 days3 days
3 sta:48,24,48 hrs
3 sta:48,24,48 hrs
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 5-10100-200 12.5-25 100-200500 62.5 500
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)
SAP sampling: 9 profiles
particles > 70 mparticles > 0.7 m
dissolved, cartridges A & B
238U(4.49 109 y)
234Th(24.1 d)
234Pa(1.18 mn)
234U(2.48 105 y)
230Th(8.0 104 y)
226Ra(1622 y)
Uranium-238 natural decay series
Total activity (dpm l-1)
0 1 2 3
De
pth
(m)
0
50
100
150
200
234Th238U
Typical profile of 234Th in the upper open ocean
C org (mg m-2 d-1)
0 50 100 150 200
23
4T
h (d
pm m
-2 d
-1)
0
1000
2000
3000
4000
5000
6000
PPS 3PPS 4PPS 5
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)