ocean respiration: new concepts, new significance, and new ... · ecoaqua ocean respiration: new...
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ECOAQUAwww . e c o a q u a . e u
OceanRespiration:NewConcepts,NewSignificance,andNew
Applications
T.T.Packard, N.Osma, I.Fernández-Urruzola, F.Maldonado, I.Martínez,A.Herrera,M.Tames-Espinosa,M.Gómez
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WhatisNewinOceanRespiration?
1. HeterotrophicEnergyProduction
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WhatisNewinOceanRespiration?
1. HeterotrophicEnergyProduction2.Carbon-FluxDepthFunctions
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WhatisNewinOceanRespiration?
1. HeterotrophicEnergyProduction2.Carbon-FluxDepthFunctions3.NutrientRetentionEfficiency(NRE)
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WhatisNewinOceanRespiration?
1. HeterotrophicEnergyProduction2.Carbon-FluxDepthFunctions3.NutrientRetentionEfficiency(NRE)4.CurvatureofRespirationProfiles:
Importance
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WhatisNewinOceanRespiration?
1. HeterotrophicEnergyProduction2.Carbon-FluxDepthFunctions3.NutrientRetentionEfficiency(NRE)4.CurvatureofRespirationProfiles:
Importance5.BenthicRespirationfrom
Water-ColumnRespiration
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HETEROTROPHICENERGYPRODUCTION
ACalculationofATPProduction
Based on nobelist,SeveroOchoa’sfinding ofa3:1ratiobetween respiratoryoxygen consumption andATPproductionandon nobelist,PeterMitchell’sChemosmotic explanation ofETS-OXPHOScoupling.
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Grupo de Ecofisiología Planctónica2008-2014
1978 Nobel Prize Chemistry chemiosmotic mechanism
ATP synthesis
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ETS ACTIVITY à RESPIRATION à ATP PRODUCTION (Joules/m3/day)
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CUEA C-Line off 15°S Peru
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Carbon Flux from Respiration
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Fc (mmol C m-2 d-1) C-Line, Peru
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Carbon Flux = ∫(R) from Riley (1951)
Ocean Bottom(mud)
Cf
RCO2
RCO2
RCO2
RCO2
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NRE=NutrientRetentionEfficiency
NRE = RCO2/(Ft-s)1
(Ft-s)1 =(d(POC)/dt)
(d(CO2)/dt) = RCO2
(Ft-s)2
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NUTRIENTRETENTIONEFFICIENCYConceptualbasis
POC, N, P Flux in
O2
CO2 (RCO2)NH4+ (RNH4+)PO4- (RPO4-)
EFFICIENCYWITHWHICHPLANKTONMINERALIZEPOMPermitsnutrient recycling!NRE=(ΔPOMFlux)/(Fluxin)
POC, N, P Flux out
RESPIRATION & MINERALIZATION!
Fluxout
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CUEA C-Line off 15°S Peru
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0!
500!
1000!
1500!
2000!
2500!
3000!
0! 2! 4! 6! 8! 10!D
epth
(m
)!R pM C min-1!
RESPIRATION !(pM C min-1)!
Rz = R0(z/zt)b
Note:”b” is always
negative!
Importanceofb,thecurvatureoftherespirationequation
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ZooplanktonRz =Rt(z/zt)-b
From:PackardandGómez,2013
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C=benthicrespiration&Cburial!
TheindefiniteintegralofRz =Rt(z/zt)b withrespectto
depth(z)is:
BENTHICRESPIRATION&C-BURIAL
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BENTHIC R & C-Burial
Tocalculatebenthicrespiration&C-burialwesubtractthefluxtothewatercolumn(Ft-s)
fromthefluxtoinfinity(F∞).
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Modelled Benthic Respiration & C Burial(µmol O2 m-2 d-1)
C-Line 15°S Peru Upwelling
C-8C-5
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R=25075z-1.204R²=0.96649
050100150200250300350400450500
0 500 1000 1500 2000
mgCda
y-1m
-2
Depth(meters)
BENTHICRESPIRATION(CO2 ProductionRate)
NWAfricanUpwelling(Christensen&Packard,1978)
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WhatisNewwiththeETSASSAY?
1. KineticAssaycutstime
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WhatisNewwiththeETSASSAY?
1. KineticAssaycutstime2.Extractioneliminated
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WhatisNewwiththeETSASSAY?
1. KineticAssaycutstime2.Extractioneliminated3.1/5reagentsneeded&1/5cost
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WhatisNewwiththeETSASSAY?
1. KineticAssaycutstime2.Extractioneliminated3.1/5reagentsneeded&1/5cost4.Sonicationusedwithzooplankton
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WhatisNewwiththeETSASSAY?
1. KineticAssaycutstime2.Extractioneliminated3.1/5reagentsneeded&1/5cost4.Sonicationusedwithzooplankton5.ComparedwithHe-tritiummethod
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MEASUREMENT of ETS ACTIVITY(Absorbance (0-0.400 in 1cm cuvettes)
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0 5 10 15 20 25
Reaction Time (0-25min)
1 m
15 m
25 m
40 m
50 m110 m
Filter Blank
Station 48EN376
Noteslopechangewith
Depth!
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0
100
200
300
400
500
0 2 4 6 8 10 12 14 16 18OUR (pM min-1)
Dep
th (m
)
#1
#2
3He-3H/AOUmethod
ETSActivitymethod
NansenBasin(ArcticOcean)
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HEP=Respiration O/PCFluxocean sectionsà RespirationNREà R/C-FluxExponent (b),the curvature ofR=f(z),
controls NRE,C-FLUX&TeffBenthic respiration &C-burialàdifferences inC-fluxintegrations
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!ACKNOWLEDGEMENTS
Supported by CIE Canarias tri-Continental Atlantic Campus (#CEI10/00018) & the BIOMBA project
CTM 2012-32729/MAR
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ZooplanktonRz =Rt(z/zt)-b
From:PackardandGómez,2013
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ECOAQUAwww . e c o a q u a . e u
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Sample 14E INT-ETS Activity
y = 0,0322x + 0,1538R2 = 0,9997
y = 0,0004x + 0,1301R2 = 0,8968
0,1
0,2
0,3
2 3 4 5 6Time (minutes)
Abs
orba
nce
(450
nm
) ZooplanktonETS
ASSAY
Substrate = 0 Assay
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R/V Eastward -1980
-50
0
50
100
150
200
250
300
0 200 400 600 800 1000
Potential Respiration from ETS activity...
1
2
R=0.26*Rp
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RESPIRATIONTRANSECT15°SPERUUPWELLING
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CN NN N Cl-+
I NO2
CN NN N
I NO2
H2H+ + 2e- -> + HCl
Light yellow
+
Scarlet red
Picks up these from the ETS substrates.
INT(Tetrazolium Violet)2-(4-iodophenyl)-3-(4-nitrophenyl)-5-phenyltetrazoliumchloride
BasicReactionoftheETSAssay
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C=benthicrespiration&Cburial!
TheindefiniteintegralofRz =Rt(z/zt)b withrespectto
depth(z)is:
BENTHICRESPIRATION&C-BURIAL
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BENTHIC R & C-Burial Model
Tocalculatebenthicrespiration&C-burialwesubstract thefluxtothewatercolumn(Ft-s)
fromthefluxtoinfinity(F∞).
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R=25075z-1.204R²=0.96649
050100150200250300350400450500
0 500 1000 1500 2000
mgCda
y-1m
-2
Depth(meters)
BENTHICRESPIRATION(CO2 ProductionRate)NWAfricanUpwelling(Christensen&Packard,1978)