organic matter metabolism in a coastal ocean ecosystem patricia matrai mike sieracki nicole poulton...
TRANSCRIPT
Organic Matter Metabolism in a Coastal Ocean Ecosystem
Patricia MatraiMike SierackiNicole Poulton
Carlton Rauschenberg
Bigelow Laboratoryfor Ocean Sciences
W. Boothbay HarborMaine
NASA OCRT 4/11-13/06 Newport, RI
In Collaboration with: University of New Hampshire
Center for Coastal Ocean Observation and Analysis
Janet CampbellJoe Salisbury
Talk outline
•Project objectives
•Study site and measurements
•Some first year results
•Respiration models
•Preliminary remote sensing results
•Conclusions
Project Objectives•Primary Objectives:
•Can microbial respiration be modeled by temperature, chlorophyll, primary production, and DOM?
•If so, how well can surface water respiration be estimated by satellite remote sensing?
•Secondary Objectives:•What is the balance of planktonic microbial respiration to primary production in a river plume system?
•How does planktonic food web structure relate to the system metabolic balance?
Gulf of Maine Primary Study Area
(GoMOOS C)
(GoMOOS B)
Study Methods• Monthly cruises from Kennebec River (Bath,
Maine) to Portsmouth, NH• 5 Stations, surface samples• Respiration (24h O2 incubations)• Primary production (12h 14C incubations)• Microplankton and particle analysis
• FlowCAM, flow cytometry, microscopy• Size spectra, 0.2 - >200 µm
• Chlorophyll, T, S, TOC, POC, ∆13C, nutrients
• Bacterial single-cell respiration (CTC)
Temperature and Salinity
0
5
10
15
20
25
Feb-05 Mar-05 May-05 Jun-05 Jul-05 Sep-05 Oct-05 Dec-05
Tem
pera
ture
°C
Stn1
Stn2
Stn3
Stn4
Stn5
Temperature pattern similar at all stations
River and plume stations show spring and fall runoff peaks (low salinity)
0
5
10
15
20
25
30
35
Feb- 05 Mar- 05 May- 05 J un- 05 J ul- 05 Sep- 05 Oct- 05 Dec- 05
Salin
ity p
su
Stn1
Stn2
Stn3
Stn4
Stn5
Bacteria and <20µm Phytoplankton Abundances
0
5000
10000
15000
20000
25000
30000
35000
40000
45000
50000
Feb-05 Mar-05 May-05 J un-05 J ul-05 Sep-05 Oct-05 Dec-05
Tota
l Euks (
mL-1
)
Stn1Stn2Stn3Stn4Stn5
0
50000
100000
150000
200000
250000
Feb-05 Mar-05 May-05 J un-05 J ul-05 Sep-05 Oct-05 Dec-05
Synechococcus (
mL-1
)
Stn1Stn2Stn3Stn4Stn5
0
500000
1000000
1500000
2000000
2500000
3000000
3500000
4000000
Feb-05 Mar-05 May-05 J un-05 J ul-05 Sep-05 Oct-05 Dec-05
Bacte
ria (
mL-1
)
Stn1Stn2Stn3Stn4Stn5
Eukaryotes
Synechococcus
HeterotrophicBacteria
Microphytoplankton Abundance(15 - 200 µm, FlowCAM)
Apr Jun Oct Dec
0
1
2
3
4
5
6
7
Feb-05 Mar-05 May-05 Jun-05 Jul-05 Sep-05 Oct-05 Dec-05
Chl
orop
hyll
ug/L
Stn1Stn2Stn3Stn4Stn5
0
100
200
300
400
500
600
700
800
Feb-05 Mar-05 May-05 Jun-05 Jul-05 Sep-05 Oct-05 Dec-05
Prim
ary
Prod
uctio
n ug
C/L
/d
Stn1Stn2Stn3Stn4Stn5
Chl
1° Prod
0
20
40
60
80
100
120
140
160
Feb-05 Mar-05 May-05 Jun-05 Jul-05 Sep-05 Oct-05 Dec-05
Mic
robi
al R
espi
ratio
n Ra
te m
l O2
/L /
d
Stn1
Stn2
Stn3
Stn4
Stn5
Seasonal Trends in Chlorophyll, Primary Production, and Respiration
Resp
Chl
1° Prod
Resp
Seasonal Trends in POC, Nutrients, and δ 13C/12C
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
Feb-05 Mar-05 May-05 Jun-05 Jul-05 Sep-05 Oct-05 Dec-05
PO
C u
g/
L
Stn1
Stn2
Stn3
Stn4
Stn5
POC
-32.0
-30.0
-28.0
-26.0
-24.0
-22.0
-20.0
Feb-05 Mar-05 May-05 Jun-05 Jul-05 Sep-05 Oct-05 Dec-05
δ1
3/C
12C
Stn1
Stn2
Stn3
Stn4
Stn5
δ 13C/12C
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
Feb-05 Mar-05 May-05 J un-05 J ul-05 Sep-05 Oct-05 Dec-05
PO4u
M
Stn1
Stn2
Stn3
Stn4
Stn5
PO4
0
1
2
3
4
5
6
7
8
9
10
Feb-05 Mar-05 May-05 Jun-05 Jul-05 Sep-05 Oct-05 Dec-05
NO
3 +
NO
2
uM
Stn1
Stn2
Stn3
Stn4
Stn5
NO3 + NO2
Annual Station Means
Downstream:Chlorophyll declines
1° Production declines
Respiration increases
0
1
2
3
1 2 3 4 5
Station
Mean C
hlo
rophyll
(µg/L
)
050
100150200250
1 2 3 4 5
Station
Prim
ary
Pro
duct
ion
(µgC
/L/d
)
0
2
4
6
8
1 2 3 4 5
Station
Mean R
esp
irati
on
rate
(µM
O2/d
)
River Coast
Chl
Resp
PP
Surface respiration vs. primary production (µgC L-1
d-1)Primary production vs. respiration
-20
0
20
40
60
80
100
120
140
160
0 200 400 600 800
Primary production (µgC/L/d)
Resp
irati
on (
µgC
/L/d
)
1:1
Overall system mean:R is 30% of P
Surface respiration vs. primary production (µgC L-1
d-1)Primary production vs. respiration
-20
0
20
40
60
80
100
120
140
160
0 200 400 600 800
Primary production (µgC/L/d)
Resp
irati
on (
µgC
/L/d
)
River + plumeAug, Sept
Spring bloomMay, June
1:1
Ecosystem relationships
Cole et al. 1988, White et al. 1991, del Giorgio et al. 1997
Rivkin & Legendre 2001
Method #1 BA = f(Chl)
BR = f(BA, T)
Method #2 BP = f(BA, T)
BR = f(BP, T)
Method #3 BR = f(NPP)
Example Gulf of Maine Respiration Images13 May 2005
SST CHL
BR1 (BA) BR2 (BP)
Conclusions
• Kennebec River plume/Gulf of Maine system is dynamic, biologically rich, and productive
Primary production exceeds respiration most of the year, R was 30% of P for the whole system over 1 year.
Preliminary estimates of respiration from remote sensing data using ecosystem relationships are within an order of magnitude of in-water measurements, but further analysis and validation are needed.
And Thanks to:
Kay Kilpatrick, RSMAS, U. Miami
Ben Tupper, Bigelow LaboratoryPaul Pelletier, Capt. R/V Gulf ChallengerChris Hunt, Mike Novak, UNH Coastal Transect crew
Carbon Cycle Science