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Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen
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Page 1: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Phytoplankton in polar regions

BIO 4400 2009 Bente Edvardsen

Page 2: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Arctic and Antarctic - similarities

• Cold • Low light during long polar winter, continuous

light during summer• Seasonal dynamics dominated by annual

formation and melting of ice• Cold high-density bottom water formation

during freezing of sea water, brine expultionand reduction of ice salinity.

Page 3: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

differencesArctic• Latitude: 70-80°N• Enclosed by land• Ocean size: 15 mill km2

• Ice cover: 14 mill km2 winter• 7 mill km2 summer• Pack ice last longer and is

thicker (av. 3.5 m)• Influenced by many large river

systems• Av. depth 1800 m and large

part over shallow shelf• Nutrient controlled

phytoplankton productionduring the summer

Southern Ocean• Latitude: 50 - 60 or 70°S• Circumpolar open system• Ocean size: 36 mill km2

• Ice cover: 20 mill km2 winter• 4 mill km2 summer• Most pack ice is one year

and thinner (av. 1.5 m)• Little terrestrial influence• Narrow shelf, pack ice over

deep water (4000-6500 m)• High nutrient, low chlorophyll

areas that may be limited by iron

Page 4: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

ArcticOcean

SouthernOcean

The maximum and minimum extent ofsea ice cover.

Page 5: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Irradiance per 24 h

theoretical values for irradiance at different latitudes

from Sakshaug et al. 1992

latitude

Page 6: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

NorwegianNorwegian, , GreenlandGreenland and and BarentsBarents SeasSeas

Page 7: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Barents Sea

Page 8: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Water circulation in the Barents Sea

Polar front

Page 9: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Barent Sea: Distribution of temperature at 100 m depth during August-September

Page 10: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Variation in ice cover distribution

Barents sea: Median values for end of April in twoperiods

(extreme)

from Blindheim 2004

Page 11: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Pack ice= ice formed at sea

Page 12: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Melosira arctica in the Arcticocean

Ice assemblages

Page 13: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

from Sakshaug et al. 1992 modified from Horner

Ice microalgalassemblages

Page 14: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Microalgal communities in the ice

from Syvertsen 1991

(skrugard-sammfunnet)

Page 15: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Ice algae

fra Syvertsen 1991

the comb effectfor trapping and colonisation of icealgae

Algae in the icewill avoid verticalmixing and somegrazing

Page 16: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Algal communities near and on the ice in the Arctic

from Syvertsen 1991

= Fragilariopsis oceanica =Attheya septentrionalis

Page 17: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Plankton- and icealgae in the Arctic

from Syvertsen 1991

plankton sub-ice Nitzschia frigida

Melosira arctica

Page 18: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Ice algaecommunities in the Barents Sea

from Syvertsen 1991

the ice edge effect –productive zone 20-50 km along the ice edge

Page 19: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Microalgal developmentin the Barents Sea

from Sakshaug et al. 1992

SPRINGsnow

multi year ice one year ice

Page 20: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Microalgal development in the Barents Sea

from Sakshaug et al. 1992

SUMMERsnow

Page 21: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Algal succession in the BarentsSea

from Sakshaug et al. 1992

the ice-edge effect

prebloom

Zooplankton spawning

overwintering zooplankton migrating up

ice edgebloom

nutrientdepleated new generation of

zooplankton developing

Capelin feedingalgae sinking

TIME

Page 22: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

marginal ice zone / ice edgeAntarctic: 100-200 km

Arctic: 20-50 km

Page 23: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Timing of vernal blooming- Arctic

Ice-edge bloom• Stratification depends on salinity (as in

fjords)• may start in April, 6-8 weeks before the

vernal bloom in the Norwegian Sea

Page 24: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Stability and production in theBarents Sea

North of polar front• strong stratification (freshwater stabilization; 20-30 m)

throughout summer• regenerated production after the spring maximumSouth of polar front• weaker stratification (temperature stabilisation)

• wind driven vertical mixing throughout summer keep up nutrient supplies

Page 25: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

South of the polar front; turbulence and ”blooming”(model), Barents Sea

phytoplankton Ncalm

with wind

Page 26: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Algal groups in the Barents Sea

Diatoms -> 100 000 cells L-1

Prymnesiophyceans; • Phaeocystis pouchetii

-> million cells litre-1

other flagellates

Page 27: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

BiogeographySpecies with preference for cold water have

competing advantages in the Arctic, but are also present in temperate waters

1. Nitzschia frigida (also in Oslofjorden)2. Melosira arctica (also in the Baltic Sea)3. Thalassiosira gravida og Thalassiosira

hyalina (also in Skagerrak)

Page 28: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Subsurface algae and bacteria

Page 29: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Summary – Barents Sea

• Hydrography; atlantic water meets polar water (polar front)

• Melting cause a brackish upper water layer that stabilise the water mass

• Spring bloom associated to the ice edge• Ice algae in and under the ice• South of the polar front: recurrent periods

with wind cause vertical mixing also in thesummer and bring up nutrients.

Page 30: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Southern Ocean

Page 31: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Hydrography

Page 32: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Antarctic bottom water

Page 33: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Deep ocean circulation

Page 34: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

F/F G.O. Sars on cruise to the Southern Ocean2008

Page 35: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Leg 2: 25 scientists from 8 countries + 12 crew

18 February- 24 March 2008

Page 36: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Stations for CTD, nutrients, chl a and phytoplankton, leg 2.

Page 37: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Aims - phytoplankton

Phytoplankton in the food web• Abundance and distribution• Species and size composition • Co variation with nutrients temp. salinity stability • Food preferences in krill

Biodiversity• Biodiversity of protists, with emphasis on nano and pico-plankton• Distribution, abundance and ecology of certain taxa

Page 38: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Sampling for phytoplankton

• Nutrients (N, P, Si)• Chlorophyll a• Chlorophyll a size

fractions• Phytoplankton

quantitative sample• Phytoplankton net haul• Pico-nanoplankton• DNA• Cultures

-36 stations, up to 8 depths

Page 39: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Phytoplankton net haul, vertically 0-100m

Page 40: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

algal culturessampling

DNA-isolation

Methods- biodiversity

electron microscopy

PCR

DNA sequencingphylogenetic

analyses

cloning454-sequencing

Page 41: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Fluo

rese

nce

/ µug

/l

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

51

53

55

56

58

59

61

62

63

65

66

68

69

71

72

73

74

Latitude °S

Pre

ssur

e / d

bar

AKES 2008

Contours at [0:0.05:.8] µug/l46 48 50 52 54 56 58 60 62 64 66

300

250

200

150

100

50

0

Fluorescence along 15oE

0

50

100

150

200

250

0 0,1 0,2 0,3 0,4 0,5

Chl a (mg/m3)

Depth

Fluo

resc

ens

Dyp

(m)

0

50

100

150

200

250

0 0,1 0,2 0,3 0,4

Chl a (mg/m3)

Depth

st. 62 st. 73

Results:

Page 42: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Thet

a / °

C, p

ref =

0 d

bar

-2

0

2

4

6

8

10

12

51

53

55

56

58

59

61

62

63

65

66

68

69

71

72

73

74

Latitude °S

Pre

ssur

e / d

bar

AKES 2008

Contours at [-2:0.5:6 7:1:12 ] °C46 48 50 52 54 56 58 60 62 64 66

1500

1000

500

0

Sal

inity

/

33.6

33.8

34

34.2

34.4

34.6

34.8

35

35.2

51

53

55

56

58

59

61

62

63

65

66

68

69

71

72

73

74

Pre

ssur

e / d

bar

AKES 2008

Contours at [33.5:0.1:34.8 35 35.2 ] 46 48 50 52 54 56 58 60 62 64 66

1500

1000

500

0

Dep

th(m

)D

epth

(m)

temperature

salinity

Hydrography

15oEHigh levels of N, P and Si south of51oS (>15,1,30 mg L-1)

Page 43: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Quantitative phytoplankton counts

0

200

400

600

800

1000

1200

1400

67- 30m 69 - 5m 72 - 50m 73 - 30m 78 - 30m 78 - 5m 78 - 75m 83 30m

Station and depth

Cel

ls/m

L

Diatoms

Cryptophytes

Ciliates

Dinoflagellates

nanoflagellates andmonads >3 my

Small pico- and nanoflagellates and monads. and small diatoms dominatedin the open ocean during this summer cruise.

Page 44: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Pico-nanoflagellates(SEM)

haptophytes, cryptophytes, prasinophytes, choanoflagellates

etc.

Page 45: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Rhizosolenia antennata f. antennata Asteromphalus parvulus

Fragilariopsis kerguelensis

Corethron pennatum

Microalgae in net hauldiatoms

Page 46: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Chaetoceros dichaeta

Chaetoceroscriophilus

Chaetocerosflexuosus

Microalgae in net haul - diatoms

Page 47: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Nanoplankton

Phaeocystis antarctica

(haptophyte)

Dactyliosolen cf. tenuijunctus

(diatom)

LM SEM

Page 48: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Pico-nanoplankton (LM og SEM)

Fragilariopsis nana

Fragilariopsis pseudonana

Page 49: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Fragilariopsis spp. (st. 63, TEM)

F. nana

F. kerguelensis

F. separanda

F. rhomboides F. ritscheri

Page 50: Phytoplankton in polar regions - folk.uio.nofolk.uio.no/steinka/roya/Phytoplankton in polar regions 4May.pdf · Phytoplankton in polar regions BIO 4400 2009 Bente Edvardsen. Arctic

Some conclusions on from theG.O. Sars cruise in 2008

• Chlorophyll levels were low (<1 mgL-1) with a maximum at 20-100 m depth

• High levels of N, P, Si in open ocean during summer

• Higher algal abundance in the polar front region and near the continent, despite lower stabilityhere, probably due to higher Fe-levels

• Nano- and picoflagellates and small diatomsdominated in numbers

• Diatoms dominated in the net hauls


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