Bergen mesocosm experiment 2011 Gisle Nondal, Richard Bellerby, Anna Silyakova, Helene Frigstad and Emanuele Reggiani London 29.09.11
Jan 24, 2016
Bergen mesocosm experiment 2011
Gisle Nondal, Richard Bellerby, Anna Silyakova, Helene Frigstad and Emanuele Reggiani
London 29.09.11
Raunefjorden, Norway
• 9 mesocoms deployed and moored
• each 25 m long with a volume of ca. 75 m3
• Initially open at top and bottom
• covered by nets with 3 mm mesh size
• enclosed water exchanging for 3 days
(Courtesy of Ulf Riebesell, IFM-GEOMAR)
Set-up
3 mesocosms moored in a rowWith anchor weights at each end
anchor weights (old railway wheels)
set of 3 mesocosms
(Courtesy of Ulf Riebesell, IFM-GEOMAR)
Target fCO2
1 2 3 4 5 6 7 8 9 180 280 390 560 840 1120 1400 2000 3000 µatm glacial pre- present 2x p.i. 3x p.i. 4x p.i. 5x p.i. industrial
CO2 Enrichment
(Courtesy of Ulf Riebesell, IFM-GEOMAR)
After 3 days:
•Closing sediment traps
•Pulling up upper bags
•Adding salt (volume determination)
•Homogenizing
•CO2 enrichment (in 4 steps)
•Nutrient addition (once)
(Courtesy of Ulf Riebesell, IFM-GEOMAR)
Sampling procedure:
Sampling at the Mesocoms with zodiacs
Gas samples directly taken on “Wassermann”
Integrating water sampler
Carbonate chemistry In situ measurements of:
Total inorganic carbon (DIC)
DIC= [CODIC= [CO22(aq)]+[H(aq)]+[H22COCO33]+[HCO]+[HCO33--]+[CO]+[CO33
2-2-]]
Total alkalinity
AAtt=[HCO=[HCO33--] +2[CO] +2[CO33
2-2-]+[B(OH)]+[B(OH)44--]+ [OH]+ [OH--]+[HPO]+[HPO44
22]+2[PO]+2[PO4433]+ ]+
[SiO(OH)[SiO(OH)33--]+ [HS]+ [HS--]+[NH]+[NH33]-[H]-[H++]-[HSO]-[HSO44
--]-[HF]-[H]-[HF]-[H33POPO44] ]
pH
pH = -log[HpH = -log[H++]]
Overdetermination!!