c-more 2: observing life, measuring the phytoplankton

8/6/2019 C-MORE 2: Observing life, measuring the phytoplankton

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C-MORE 2: Observing life, measuring the phytoplanktonOscar Schofield (RU COOL)

Picture by Chris Gotschalk


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Enough energy make something new( )rearrange a molecule

Enough energy to excite( )vibrate a molecule Enough energy move electrons

Phytoplankton growth and nutrient assimilation is tied to ambient light levels.


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Photosynthesis = PAR * aph *

aph =

a(l )*Eo(l )dl400nm

700nm

Eo(l )dl400nm

700nm

Spectrally averaged absorption

Energy that is into the cell, ,Varies cell pigmentation light history

and size

~ 1%

)()()(

ddd EKdz

dE=

0.00 0.20 0.40 0.60 0.80 1.00

Irradiance

0.00

20.00

40.00

60.00

80.00

100.00

Depth

(m

)

lar visible irradiance

gy in

to the oceanes with depth according to the IOPs

with radiative transfer eqns describe the AOPS

Efficiency of converting energy in( , ,End product electrons oxygen carb

Varies with end product and physiol

..Quantum efficiency of

Hi

gh

Low

Absorption

Fluorescenceor charge

separation

oxygen

carbonfixation

growth


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Every day, the ocean changes colourEvery day, the ocean changes colour

or rather, it passes though a varietyor rather, it passes though a variety

of hues between the morning, noonof hues between the morning, noon

and night of a single day. The subtleand night of a single day. The subtle

shapes of clouds, the glittering lightshapes of clouds, the glittering light

of the sun, and the shifts inof the sun, and the shifts inatmospheric pressure tint the seaatmospheric pressure tint the sea

with deep tones, cheerful tomes,with deep tones, cheerful tomes,

plaintive tones that would cause anyplaintive tones that would cause any

painter to pause in wonder.painter to pause in wonder.

fromfrom The SamuraiThe Samurai by Shusaku Endoby Shusaku Endo

(1980)(1980)


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Eyeball Optics

The Secchi Disk:

First systematic usage reported in 1866, butobserved and remarked upon much earlier.

Early experiments carried out by CommanderCialdi, head of the Papal Navy, and ProfessorSecchi onboard the SS LImmacolataConcezione (Cialdi, 1866).

Used operationally for establishing aids tonavigation over shallow water.

Thanks to Marlon Lewis


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From John T. O. Kirks billabongs

Measuring the light into the system


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Reflectance( ) = G* bb( )/{bb( ) +a( )}

Wh t f th l i l DIMS?


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What are some of the classical DIMS?

Claustre et al.

Diatoms 0.114 + 0.051Cryptophytes 0.053 + 0.011

= P/(Qpar(0+))

Localweather

seasonal

Morel and Platt show * variabilityOf 50% around a value of at specific

chl values


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Penetration of light is determined by the material in the waterwhich is determined by the overall inherent optical properties (IOPs)

( )Absorption a color

.Photos by S Etheridge


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( )Scattering b clarity

+ =a b c=c attenuation

From Collin Roesler


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detector detector

( )Absorption a ( )Attenuation b

WetLabs


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Scattering Case I waterscp(660) bp(660)

Loisel and Morel 1998B

p ChlAc =)660(

Positivelycorrelated Non-linear, B 0.7

High


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Particle backscattering

Cannizzaro et al. 2002

West Florida Shelf

Karenia brevisbloom

POC S i (C I )


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POC Scattering (Case I waters)

Loisel and Morel 1998

Bp POCAc =)660(

B 1

Subtropical Pacific, North Atlantic

Contrast with non-linear

dependence on Chl

POC-Chl variationsare important


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Bottom layer

POC-Scattering

Gardner et al. 2001

New England Continental Shelf

Surface layer

cp(660)

Under specific conditions, the cp POC relationship varies


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E.m. radiation propagating as plane waves;E.m. radiation propagating as plane waves; gg

geometric crossgeometric cross

section (its shadow )section (its shadow )

EFFICIENCY FACTORSEFFICIENCY FACTORS

Energy absorbed withinEnergy absorbed withinEnergy scattered out by..Energy scattered out by..

DividedbyDividedby

Energy impinging onEnergy impinging on ggQaQa andand QbQb , respectively, respectively

From beautiful work of Morel, Bricaud, and Kirk


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Durand et al. 2002


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Positivelycorrelated

Chl: 0.02 25mg m-3

(eutrophic,mesotrophic, and

oligotrophicwaters)

Bricaud et al. 1995Non-linear dependence

Thanks to Heidi Sosik


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Chl-specific phytoplanktonabsorption

Second-order

variability in aph ()

)(* )()( Bph ChlAa =

Chl

aa

ph

ph

)()(*

=

A( ) and B( )

statistically determined

This reflects effects of changing growth conditions andcommunity structure with trophic status

Note: unexplained variability

Negatively correlated


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Low light

High light


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Low light

High light

Photosyntheticpigments

Photo-protectivepigments

chlorophyte alga Haematococcus pluvialis


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2 0 22 0 42 0 62 0 82 1 02 1 22 1 4

0

2

4

6

8

0

2

D

e

p

th

(m

)

2 0 22 0 42 0 62 0 82 1 02 1 22 1 4

0

2

4

6

8

0

2

D

e

p

th

(m

)

0

0.3

0.6

0.9

1.2

400 450 500 550 600 60

500

1000

1500

2000

molph

otons(m

-2

s-1

)

Depth( m

)

Calendar Day

B

mol photons m-2 s-1

C

Calendar Day

D

(m-1)pha

Depth( m

)

0 22 0 42 0 62 0 82 1 02 1 22 1 4

500

1000

1500

2000

0

0

0.3

0.6

0.9

1.2

400 450 500 550 600 650

0

0 . 3

0 . 6

0 . 9

1 . 2

4 0 04 5 05 0 05 5 06 06 57

surface

1m

2m

5m13m

Wavelength (nm)Calendar Day

A

0 6 3 31 2 6 71 9 0 0

0 .0 0 0 .1 6 0 .3 1 0 .4 7

.Oliver et al 2004


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Vertical migration ofKarenia brevis


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0.0

0.02

0.04

0.06

0.08

400 450 500 550 600 650 700

chl achl b

chl c

PSC

PPC

wavelength (nm)

absor

ption

coef

ficient( m

2 m

g-1

)

From Bidigare

Individual pigments can be measured on discrete samples biochemically


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0

5

10

15

20

400 450 500 550 600 650 700

Wavelength (nm)

SpectralIrra

di ance(

W

cm-2

nm

-1)

chl a chl achl b

chl c

chl bcarotenoids

phycobilins

0

0.25

0.50

0.75

1.0

1.25

Relativ

eAbsorption

chl a-chl c-carotenoidschl a-chl b-carotenoids

chl a-phycobilins


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0

20

40

60

80

1000 1 2 3

D

epth

(m)

Relative pigment-specific

spectrally weighted absorption

B)

Decreasing efficiency Increasing efficiency

Chl a

Chl bPSCChl c

Wavelength (nm)

0.00001

0.0001

0.001

0.01

0.1

1

10

400 500 600 700

Spectralirra

diance(

Wcm

-2s-

1)

1

25

90

Sun stimulatedfluorescence

A)


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Absorbed photon Charge stabilization &

photosynthesis

Heat

Fluorescence


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ChlorophyllChlorophyll a -a - Fate of photonsFate of photonsabsorbed by an isolated moleculeabsorbed by an isolated molecule

Diagram of energy states in chlorophyll and possibletransitions


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Alexander Graham Belldeveloped spectrophone,

essentially an ordinaryspectroscope equipped with

a hearing tube instead of aneyepiece listening to lightinduced changes in the

thermal sound.

Light Absorption

Heating

Thermal Expansion

PressureWave

Photoacousticsignal


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Weak light flash

Strong light flash


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Light

Quantu

m

yield

max


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Fluorescence


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Chlorop h

yllfluorescen

ce

Chlorophyll concentration

An

idealw

orld

Stress(light, nutrients)


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8:00 12:00 18:00 22:00

5

10

15

20

Local DaylightTime

0

Depth(m)

CDOM

8:00 12:00 18:00 22:00

5

10

15

20

0

D

epth( m

)

Chl a

mixed

chromop

hyte

community

m

onospe

cific

G.breve

c

ommunity

Local DaylightTime


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Fluorescence: The Basics

F0 = aph PAR

kf

kp +kf+kd

Fm = aph PARkf

kf+kd

Fv = aph PARkf

kp(Q)+kf+kd

Fm - F0

Fm=

kp

kp +kf+kd=fIIe

o

time

Fluores

cencei n

tensity

F0

Fm

Ft

Saturating flash

Fm

Other useful indices


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Time

Fluores

cencer i

se

Integrated area isreflection of the absorption

cross-section

Flash is onRC2

Highlightcells

Lowlightcells

Photo-acclimation

Photons

Other useful indicesFLUORESCENCE INDUCTION


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Fluorescence

deca

yconstan

ts

Localtimeofday

Time

Other useful indicesFLOURESCENCE DECAY CONSTANTS

LightFlash

TurnedOff

Fluores

cenc

e

RC

Pheo

Qa

Qb

PQ

D1

D2


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0

2

4

6

8

10

0.1 1 10 100 1000

0.4

0.5

0.6

0.7

0.8

Irradiance ( mol photons m-2 s-1)Produ

ctivity

(mgCmgC

hl

a-2h

-1)

0

0.02

0.04

0.06

0.08

0.1

CarbonQ

ua n

tumY

ield

(molCmol p

hoton

sabsorb

ed-1

)

Fv/Fm

Pmax

Ik

max

Environmentalstress


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From Jassby and Platt 1976

Is a cell a puddle or lake?


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fluorescence-based predictions of oxygen evolution

m

easur

edoxygenev

olution

0

1

2

3

4

5

6

0 1 2 3 4 5 6

R

2

=0.92, P


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Photosynthesis a chain of cascading reactions:

Each step sets the upper limit efficiency for each following step down the line

mpsii (0.65) > m02 (on the order 0.125)> mco2 (on the order 0.07)

For each use of energy go to one process, it is the expense of

another reaction, this impacts the overall efficiency

Nutrient source mco2Ammonium 0.09Nitrate 0.07

Simplest expression for photosynthesis is

P = * aph * PAR

While chlorophyll specific absorption varies 3-4 fold


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From Babin et al.

p y p pquantum yields vary by an order of magnitude

Even in 1980s was treated as a constant


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From Behrenfeld et al.

The con ersion efficienc can aries bet een end prod cts


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0

2

4

6

8

10

12

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

Absorbed Quanta by phytoplankton

Light-saturated photosynthesis

Light-limitedphotosynthesis

RatioofOxyge

ntoCa

rbonQ

uantum

Y

ields

The conversion efficiency can varies between end products


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These instruments can be carried on remote platforms


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0.00

0.25

0.50

0.75

5:00 9:00 13:00 17:00 21:00

0

400

800

1200

1600

PAR

molm

-2s

-1)

Fv/Fm

EPS

Local Daylight Time

0

0.2

0.4

0.6

6:00 10:00 18:0014:00

Local Daylight Time

Fv/F

m

0

200

400

600

800Visible light downregulation

UVBdamage

PAR(

molm

-2s

-1)

UVB + UVA + PARUVB + UVA + PAR

UVA + PARUVA + PAR

PARPAR

Ik>PAR Ik>PAR

Physiological response Environmental Stress

)Rough seas


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50 100 150 200 250 300 3500.005

0.025

0.045

0.065

0.085

0.105

0.125

1

2

3

45

6

7

8 9

10

11

12

13

14

1516

171819

20

21

22

23

New Jersey Coastal Region22 Southern California Bight21 NW Atlantic Continental Shelf (Spring)

20 Gulf Stream (Spring)19 NW Atlantic Subtropical Gyre (Spring)18 NE Atlantic Subtropical Gyre (Spring)17 Canary Islands (Spring)16 NW Atlantic Continental Shelf (Fall)15 Gulf Stream (Fall)14 NW Atlantic Subtropical Gyre (Fall)13 NE Atlantic Subtropical Gyre (Fall)12 Canary Islands (Fall)11 Antarctic (Palmer Station)10 Antarctic (Transitional Weddell Water)9 Antarctic (Bellingshausen Warm water)8 Antarctic (Bellingshausen Cold water)7

Arabian Sea (NE Monsoon)

6

Arabian Sea (Inter Monsoon)

5

Arabian Sea (SW Monsoon)

4321

Antarctic (Bransfield-Bellingshausen water)Antarctic (Bransfield-Weddell water)Antarctic (Ice-Edge water)Antarctic (Weddell-Scotia Confluence waters)

23

Ek(PAR) (mol photons m-2 s-1)

max

(molC m

olp

hotonsa

bs

orbed

-1)

Oligotrohicseas


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-caroteneglobules

thylakoids

Low lightHigh light

NUTRIENT LIMITATIONS


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NUTRIENT LIMITATIONS

Iron-Ex


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Nutrient concentration (can be nitrogen, phosphorus)

Nutrie nt

Uptake(V

)

Vmax

Ks (usually at Vmax/2)

Austin Powers FatBastard System

Miss Manner System

V=Vmax*S/(Ks+S)V=Vmax*S/(Ks+S)


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Diatoms

High VmHigh Ks

Coccolithophores

Low VmLow Ks

High or fluctuating nutrientsHigh mixing, upwellingLow average irradiance, light

fluctuationsHigh turbulence

Chronically oligotrophicStratified conditionsHigh average irradiance

Low turbulence


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0.8

1Vmax

y

10

12


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depth

light

Chlorophyll

Ek

c-more 2: observing life, measuring the phytoplankton

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