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4.E+07

1.5

3.E+07

1

2.E+07

0.5

1.E+07

0

0.E+00

-0.5

27/7 28/7 29/7 30/7 31/7

2/8

3/8

4/8

5/8

6/8

7/8

8/8

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9/8

2

12

1.5

11

1

10

0.5

9

0

8

-0.5

4.E+10

1/8

2/8

3/8

4/8

5/8

6/8

7/8

8/8

9/8

10/8 11/8 12/8 13/8

Growth rate (d-1)

Biovolume (µm3/L)

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2.E+10 0.5

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600 400

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200 0

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32

34

36

38

40

42

800

400

700

350

600

300

500

250

400

200

300

150

200

100

100

50

44

0

& Depth of the cells Z(t)

([SHULPHQWV DUH UHSURGXFLEOH ERWK FXOWXUHV SURYLGH FORVH UHVXOWVIRUFDUERQ DQG FKORURSK\OO DFHOOXODUFRQWHQWV )

450

0 25

30

35

Chemostat 1

40

45

Days

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6

800 700 600

sec )

-1

4

500 3 400 300

2

200 1

-1

5

PAR (µmol quanta m

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Days

7.0E+7

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6.0E+7

5.0E+7

4.0E+7 2.E-6 3.0E+7

2.0E+7 0.E+0

-2.E-6

0.0E+0

25

30

35

40

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45

100 0

0 25

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Chemostat 2

900

f

45

Cell Carbon content

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Continuous cultures and samplings under fluctuating conditions of light intensity

40

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- Attenuation Æ Irradiance at Z(t)

-2

Surface irradiance

10/8 11/8 12/8 13/8

-1

e Lagrangian transposition

900

Cell Chlorophyll a (pg Chla cell )

30

9/8

35

Days

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8/8

Cell carbon (pg C cell

-80

7/8

-1

800

6/8

(YROXWLRQVRIFDUERQDQGFKORURSK\OO D

sec )

1000

5/8

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-40

4/8

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0

1200

3/8

30

1.0E+7

PAR (µmol quanta m

Irraidance (µmol.quanta/m²/s)

1400

26

2/8

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Depth (meters)

Depth

Zm

1/8

25

4.E-6

-0.5

27/7 28/7 29/7 30/7 31/7

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0

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d Taking account light attenuation and photoperiod

40

6.E-6

0

0.E+00

10

0

2

1

1.E+10

60

20

1.5

3.E+10

15

5

13

27/7 28/7 29/7 30/7 31/7

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10/8 11/8 12/8 13/8

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NO3 NO2

80

Division rate (d-1)

Mean diameter (µm)

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0

1/8

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Cell density (n l -1 )

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20

100

NO 3 (µM)

5.E+07

-1 -1 ρ(NO3) [µM cell d ]

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100%

Growth rate (d-1)

Cell number (n/L)

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NO 2 (µM)

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30

35

40

45 Days

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