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PALEO RECORDS OF BIOTIC AND ABIOTIC PARTICLES IN POLAR ICE CORES
John Priscu, Christine Foreman, Joe McConnellMontana State University & DRI, Reno, NV
Where Am I Going?
•Methods
•WAIS particle characteristics (biotic andWAIS particle characteristics (biotic and abiotic)
Dissolved Organic Carbon (food for bugs!)•Dissolved Organic Carbon (food for bugs!)
•Metabolic activity
•Microbial habitats in ice
•Geochemistry (DOC, Sr, Ca)
Flow cytometry uses the principles of light scattering , light excitation, and emission of fluorochrome molecules to generate specific multi-
FLOW CYTOMETRY
parameter data from particles and cells in the size range of ~0.2 µm to 15µm diameter.
(Differentially stained to ( yDetect DNA-SYTO 60)
Comparison of a sample from Lake Vostok ice core 2334, using a coulter counter and the flow cytometer Coulter counter data kindly provided by Ellen Moseley Thompson of Byrd Polarcytometer. Coulter counter data kindly provided by Ellen Moseley‐Thompson of Byrd Polar Research Center, Ohio State University.
Method Vostok core 2334
Coulter Counter(particles ml-1) 24994(particles ml 1) 24994
Flow cytometerFlow cytometer(particles ml-1) 27818
Fl C t t D tWAIS Divide Core WDC05Q Stick D
Flow Cytometer Data
Fig. X. Biotic (bacteria) and abiotic particle distribution from a shallow WAIS Di id ti bt i d ith Mi t fl t tWAIS Divide core section obtained with a Microcyte flow cytometer.
Abiotic V1686
4000
Abiotic V2334 Abiotic V3612
300
Vostoc Ice Core Particle Characterizationue
ncy
2000
3000
4000
uenc
y
400
600
uenc
y 200
300
A C E
Avg size (µm) = 0.60 Avg size (µm) = 1.24Avg size (µm) = 2.63
Freq
0
1000
2000
Freq
0
200 Freq
0
100
Avg size (µm) 0.60
Size (µm)
0 3 6 9 12 15
Biotic V1686
Size (µm)
0 3 6 9 12 15
Biotic 2334
Size (µm)
0 3 6 9 12 15
Biotic V3612
ency
75
100
ency 75
100
ency
20
30B D FAvg size (µm) = 2.45 Avg size (µm) = 1.60Avg size (µm) = 3.74
Freq
ue
0
25
50
Freq
ue
0
25
50
Freq
ue0
10
20
Size (µm)
0 3 6 9 12 150
Size (µm)
0 3 6 9 12 150
Size (µm)
0 3 6 9 12 150
CORE ID: WDC05Q Stick D
Epifluorescence microscope countsDNA stained sample (SYBR GOLD)
WDC 05Q Stick D; 86 96 mWDC 05Q Stick D; 86.96 m
Epifluorescence microscope countsEpifluorescence microscope countsDNA stained sample (SYBR GOLD)
WDC 05Q Stick D; 86.96 m
“ATTACHED BACTERIA”
5 µm
3 µm
BACTERIAL ACTIVITY IN ICY SYSTEMS1000 G k ll A t i
h-1 ) 100
1000 snow, Gossenkollesee, Austrialake ice, Gossenkollensee, Austrialakewater, Piburgersee, Austrialakewater, Tai Hu, Chinacloud droplets Austria (3100 m)
on (n
g C
l-1
1
10
cloud droplets, Austria (3100 m)snow, Austria (3100 m)lakewater Gossenkollesee, Austrialake ice, Lake BonneyBlood Falls, Taylor Glacier
rial P
rodu
ctio
0.1
1 , ysnow, North Polesnow, South PoleColle Gnifetti Gl, SwitzerlandRotmoos Glacier, Austria
WAIS
Bact
er
0.01
Canada GlacierRhone GlacierTaylor Glacierleast squares fit
Bacterial C (ng C l-1)
1 10 100 1000 10000 100000 10000000.001
Data from B. Sattler Average carbon turnover time = 63 days and J. Priscu (melted
Cores; ~1 oC incubation)
1 micron fluorescent beads in an ice vein.
1 micron fluorescent beads in an ice vein subjected to a 0.2 oC temperature gradient (Avg ice temp = ‐15 oC)p g ( g p )
GEOCHEMISTRY
GEOCHEMISTRY
DOC of Seawater Origin?
TAKE HOME LESSON: OLD VIEW
Typical Numbers of Prokaryotic Typical Numbers of Prokaryotic C ll i N t l H bit tC ll i N t l H bit tCells in Natural HabitatsCells in Natural Habitats
Habitat Cells ml -1Colon/Rumen 0.1-1 x 1010
Soil 0.1-100 x 107
Marine (open water) 0.05 - 460 x 106( p )Fresh and saline lakes 1.0 x 106
Rivers 1.0 x 106Rivers 1.0 x 10Ocean sediments 0.34 - 220 x 106
Glacial ice 1 0 2 0 X 103Glacial ice 1.0 - 2.0 X 103
Background data from Whitman et al. 1998, “Prokaryotes: the unseen majority”, PNAS, 95:6578-6583.
Future PlansFuture Plans
•Try to make continuous measurements (or discrete samples using aTry to make continuous measurements (or discrete samples using a fraction collector)?
→Or would it be best to work on annual cycles (i.e., melt a l th f i ti )?length of ice representing one year)?
•Examine diversity using genomic methods (most easily done if we worked on ice cores integrated over a year)
•Directly measure the mass of particulate organic C and NDirectly measure the mass of particulate organic C and N
•Continue our attempts to measure metabolism in situ