Marine biogeochemical cycles - PML NOCS MBA by sdsdfqw21

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									          Marine biogeochemical cycles
Theme 2

                  Marine biogeochemical cycles &
           PML    feedbacks in a high CO2 world

          NOCS    The ocean’s biological carbon pump
                  and its sensitivity to climate change

                  Cellular and molecular responses of
           MBA    calcification to rapid global change
          Marine biogeochemical cycles
Theme 2


           PML       Marine biogeochemical cycles and
                     feedbacks in a high CO2 world
                     •   Improved quantification of the carbon
              Main       cycle in the surface ocean and shelf seas
          elements   •   Reducing uncertainties in the microbial
                         cycling of the major elements

                     •   Quantifying the impact of a high CO2 world on
                         marine biogeochemical cycles and feedbacks
                     •   Links between photophysiology, stress
                         responses and biogenic gas production

           Leader    Phil Nightingale pdn@pml.ac.uk
                             Approach
Fieldwork
2007    SOLAS DOGEE                    4 day add on + theme 2 berth
        SOLAS INSPIRE                  theme 2 berths

2008    SOLAS D326 (Dust cruise)       theme 2 berth
        SOLAS ICON:                    4 day add on + theme 2 berths

2009    Time Series at L4              Add on to S10

2010    Enhanced Autumn AMT            Add on to S01

2011    Enhanced Spring AMT            Add on to S01



Labwork
07-12   Lab expts with cultures and/or samples from S10 (& S01)
          Marine biogeochemical cycles
Theme 2


           PML       Marine biogeochemical cycles and
                     feedbacks in a high CO2 world
                     •   Improved quantification of the carbon
              Main       cycle in the surface ocean and shelf seas
          elements   •   Reducing uncertainties in the microbial
                         cycling of the major elements

                     •   Quantifying the impact of a high CO2 world on
                         marine biogeochemical cycles and feedbacks
                     •   Links between photophysiology, stress
                         responses and biogenic gas production

           Leader    Phil Nightingale pdn@pml.ac.uk
        DOGEE SOLAS
                   Air-sea fluxes measured using
                       Deliberate tracers
                       Eddy covariance (DMS, CO2, 02)

                   Measurement of physical variables
                      inc bubbles, waves & turbulence

                   UK: PML, NUT, NOC-S, UEA
                   US: Miami, Hawaii, Montana, LDEO,
                   PML Contribution: SOLAS & OC2025 funded




               OVOCs
Is there biological uptake of CH3OH?
                              Biological removal of methanol in seawater

                                                                                                            3H
                                                                                                             Leucine Uptake
                   14C   Cellular Methanol Uptake                                                       (Bacterial production)


                   0      1     2   3   4                      0   1   2    3      4                        0    5     10        15
                                                           0                                            0
               0

                                                          20                                           20

         250
                                                          40                                           40
D ep th (m )




                                             Depth (m)




                                                                                        D ep th (m )
         500                                              60                                           60


                                                          80                                           80
         750                                                                                                                01-Jul
                                                         100                    1-Jul             100
                                                                                3-Juy
    1000                                                 120                    4-Jul             120


                   Deep Cast                                               Euphotic Zone
                     25
                                                                                                                             Diel Cycling
                     20
                                                                                                                            Unfortunately weather
CH3 OH uptake




                     15                                                                                                     deteriorated & we were
                                                                                                                             unable to manoeuvre
                     10


                      5                                                                                              Total methanol utilisation rates
                                                                                                                                250-750,
                      0

                                                                                                                        ie 120 times higher than
                         0

                                  0

                                         0

                                                0

                                                       0

                                                              0

                                                                     0

                                                                            0

                                                                                   0

                                                                                          0

                                                                                                 0

                                                                                                        0

                                                                                                               0
                      :0

                               :0

                                      :0

                                             :0

                                                    :0

                                                           :0

                                                                  :0

                                                                         :0

                                                                                :0

                                                                                       :0

                                                                                              :0

                                                                                                     :0

                                                                                                            :0
                    07

                              09

                                   11

                                         13

                                                15

                                                       17

                                                              19

                                                                     21

                                                                            23

                                                                                   01

                                                                                          03

                                                                                                 05

                                                                                                        07
                                                                                                                        particulate uptake rates.
                   350000
                                                             SF6 continuous
                   300000

                   250000
SF 6 (Peak Area)




                   200000

                   150000

                   100000

                    50000

                          0                                                                                        Similar diel cycle seen in INSPIRE
                      08 2
                      09 2
                      10 2
                      12 1
                      13 2
                      15 2
                      16 1
                      17 8
                      18 8
                      19 9
                      20 9
                      22 8
                      23 8
                      00 1
                      01 1
                      02 0
                      04 0
                      05 0
                      06 9
                           9
                        :0
                        :1
                        :2
                        :3
                        :4
                        :5
                        :0
                        :1
                        :2
                        :3
                        :4
                        :5
                        :0
                        :2
                        :3
                        :4
                        :5
                        :0
                        :0
                        :1
                     07
          Marine biogeochemical cycles
Theme 2


           PML       Marine biogeochemical cycles and
                     feedbacks in a high CO2 world
                     •   Improved quantification of the carbon
              Main       cycle in the surface ocean and shelf seas
          elements   •   Reducing uncertainties in the microbial
                         cycling of the major elements

                     •   Quantifying the impact of a high CO2 world on
                         marine biogeochemical cycles and feedbacks
                     •   Links between photophysiology, stress
                         responses and biogenic gas production
Volatile Iodine Compounds
                                  INSPIRE
                                 Nov/Dec 07



                              Measurements of
                               CH3I, CH2ClI,
                              CH2BrI, CH2I2 etc


                              Use of isotopes to
                                  determine
                              consumption and
                               conversion rates


                              Collaboration with
                                    UEA

     D326 (Dust Cruise)
                               PML Contribution
        Jan/Feb 08           SOLAS & OC2025 funded
Rate measurements repeated
       OC2025 funded
          Biological oxidation of methyl iodide (CH3I) in the ocean.
                                                                                               APPROACH
                                 Air-sea gas exchange
                                                                                         14CH I   added to seawater
                                                                                             3
                                            Lex
                                  Phv                      LB
                                                                      Biology                       Respired
         Photochemistry                                               bacterial
                                           [CH3Isw]                  metabolism?                    14CO
                                Lhv                        PB                                              2

                                                      LC
                                                                                               ppt with SrCl2
                                           Chemistry                                         Quantified by liquid
                                                                                            scintillation counting
                            near surface
               0.0012
                            7% light                                       First direct measurements of LB:
                            control
               0.0010                                                      Loss rate constant: 0.0005 – 0.0050 d-1
added




               0.0008                                                      Biological turnover: 50 -1400 d
14CO /14CH I
          3




               0.0006

               0.0004
    2




                                                                           Mixed layer loss, using in situ concentrations:
               0.0002
                                                                           Lc (Elliot & Rowland 1993): turnover ~ 30d
               0.0000
                        0         10                  20        30         Lex (Archer et al. 2007): turnover ~ 40d
                                           Time (h)
R egenerated
                Rates of new and regenerated nitrogen production
               Excretion - degradation   NH4
  N itrogen
               (bacteria/zooplankton)    DON (urea &)                                                             Challenge:




                                                        Phyt opla nkto
                                                        Phyt opla nkto n Prod uctio n
                    Nitrification                                                                     To create basin scale estimates of
                                         NO3
                     (bacteria)                                                                                New Production
                  Deep water supply
                                                                                                         accounting for nitrification,
                    (vertical flux)      NO3                                                         nitrogen fixation & DON utilisation
 N itrogen




                  Nitrogen fixation
                                         N2
    N ew




                                                                              uctio n
                   (cyanobacteria)

               Atmospheric deposition    NO3 & NH4                                                 0.9
                                                                                                             y = 0.1032Ln(x) + 0.104
                                                                                                   0.8       r2 = 0.76
                                                                                                   0.7
                                                                                                   0.6




                                                                                        f'-ratio
                                                                                                   0.5
                                                                                                   0.4
                                                                                                                y = 0.1153Ln(x) - 0.021
                                                                                                   0.3          r2 = 0.92

                                                                                                   0.2
                                                                                                   0.1
                                                                                                                                                 a)
                                                                                                   0.0
                                                                                                         0                   200           400   600
                                                                                                                              NO3- (mmol m -2)

                                                                                                   Atlantic (AMT) f-ratio:NO3 relationship
                    INSPIRE 2007
          Marine biogeochemical cycles
Theme 2


           PML       Marine biogeochemical cycles and
                     feedbacks in a high CO2 world
                     •   Improved quantification of the carbon
              Main       cycle in the surface ocean and shelf seas
          elements   •   Reducing uncertainties in the microbial
                         cycling of the major elements

                     •   Quantifying the impact of a high CO2 world on
                         marine biogeochemical cycles and feedbacks
                     •   Links between photophysiology, stress
                         responses and biogenic gas production
Adaptation of phytoplankton cultures
          to elevated CO2


                            Cultures of Thalassiosira
                          pseudonana bubbled with
                          current and doubled pCO2

                            In batch cultures pH
                          increases with increasing cell
                          density

                            In our continuous cultures
                          pH is constantly monitored
                          and maintained through
                          automated influx of fresh
                          media
Adaptation of phytoplankton cultures to elevated CO2
                  pH of continuous cultures of T. pseudonana during initial 3 weeks of
                                              experiment

            8.8

            8.6

            8.4

            8.2
       pH




             8

            7.8

            7.6

            7.4
                  0   48    96      144   192    240     288    336   384   432       480   528   576
                                                       time (hours)

                                 760 ppm CO2 1          760 ppm CO2 2         760 ppm CO2 3
                                 air 1                  air 2                 air 3




  Stable long term cultures                                           Transcriptional regulation of carbon
                                                                      anhydrase and rubisco genes in
  Automated pH regulation is                                          carbon assimilation
performing well for continuous                                        C:N partitioning
cultures                                                              Metabolite profiling

   Samples taken at regular intervals                                 Photosynthetic efficiency
for future analysis including
 Effect of increasing atmospheric CO2 and trace gas production
                                                      Mesocosm experiments in Norway
                                                      tested the effect of pCO2 levels
                                                      projected for the next century.

                                                      High pCO2 led to reductions in DMS &
                                                      iodocarbons

                                                      UEA/PML collaboration



                Present (36 ppm)   Glacial (180ppm)




Future mesocosm experiments planned

Svalbard Arctic 2009

Free-floating N. Atlantic 2010

Co-funding via EU EPOCA
Collaboration with Kiel, Germany
          Marine biogeochemical cycles
Theme 2


           PML       Marine biogeochemical cycles and
                     feedbacks in a high CO2 world
                     •   Improved quantification of the carbon
              Main       cycle in the surface ocean and shelf seas
          elements   •   Reducing uncertainties in the microbial
                         cycling of the major elements

                     •   Quantifying the impact of a high CO2 world on
                         marine biogeochemical cycles and feedbacks
                     •   Links between photophysiology, stress
                         responses and biogenic gas production
  Glycine betaine in terrestrial plants: enhances tolerance to
                                 plants
  photoinhibition and reduces ROS production (Prasad & Saradhi 2004).
  Similar role in algae?
Intens.
    7
  x10                                                                                                                   Total Ion Current
      2.5
                                                                                                                                               • Developed LC-MS method
      2.0                                                                                                                                      which improved sensitivity of
  x107
                                                                                               Extracted Ion Chromatogram m/z 118              detection of GBT over HPLC
                          CH3   O
                                                                                                                                               by three orders of
      0.8
                                    Glycine betaine (GBT)
                      H3C N+
      0.4
                       H3C          O                                                                                                          magnitude.
      0.0
                          1             2                    3                    4            5              6                            7
                                                              Retention Time [min]


                                              Conc (ng/L)
                  0       100           200                 300                400       500
             0

                                                  • Improved sensitivity permitted first depth profiles of glycine
                                                  betaine in open ocean
                                                                                                                                  80
            40
                                                                                                                                                              +UV
                                                                                                                                  60
                                                                                                                                                              - UV

                                                                                                                  GBT (fg/cell)
Depth (m)




                                                                                                                                  40
            80


                                                                                                                                  20


                                                                          GBT 14th Jan
            120                                                           GBT 23rd Jan                                             0
                                                                          GBT 24th Jan                                                 0            60                 120       180
                                                                                                                                                         Time (min)
                                                                          Chl 23rd Jan
                                                                                                                                           Stress                     Recovery

            160                     SOLAS/OC2025                                                   • GBT measurement during photophysiology expts
Chlorophyll catabolism: regulated chlorophyll destruction pathway in higher plants
             catabolism
Chlorophyll catabolism under algal stress: mechanism against ROS production?
                                                                                                                                                 627

                                                                                                                       Full MS                           [M+H]+




                                                                                            Relative abundance
                                                         O
                                                 H
                                                 ON
                                            NH                                                                                            569
                                                                                                                                                   628
                                            N        N
                                                     H
                                                                                                                                                           [M+Na]+   250   Wavelength / nm   700
                                                                                                                                  551              650
                                                                                                                                             591
                                            O            O
                                                 OMe
                                        O   OH                                                                         450 500 550 600 650 700 750
                                                                                                                                             m/z
• Production of chlorophyll catabolites from Chlorella (Engel et al. 1991) permitted development
of HPLC and LC-MS methods for their characterisation


                               25
                                                                                                                                                       • Chlorophyll catabolite
                                                                                                                                                       detected in DOM during
                                                                                                                                                       Isochrysis galbana senescence:
                                                                         12
                               20                                        10
                                                              Response




                                                                         8




                               15
                                                                         6

                                                                         4                                                                             First evidence of chlorophyll
                                                                                                                                                       catabolites in marine algae.
                    Response




                                                                         2

                                                                         0
                                                                          240   290   340   390                  440   490    540   590    640
                                                                                            Wavelength / nm
                               10

                                                                                                                                                       • Next step: Tracking
                               5                                                                                                                       chlorophyll catabolites during
                                                                                                                                                       viral infection of algal host.
                               0
                                    3   8                13                           18                                     23                  28
                                                         Retention time / min

								
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