Final progress report
AR-WSL, EPFL ECOS
Andy Siegenthaler
Emanuela Samaritani,
Edward Mitchell,
Alexandre Buttler
RECIPE meeting Aberdeen 29-31 May 2006
Growing keystone species experiment
June 2004-July 2005
WP II
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
D20, D21, D23
Basal respiration WPII
Effects of different keystone species on CO2 and CH4
production and emissions at various water levels.
Gas
CO2
CO2
Water table E. angustifolium E. vaginatum
Low
0
0
Intermediate
+
++
CO2
CH4
CH4
CH4
High
Low
Intermediate
High
Gas
CO2
CO2
Water table E. angustifolium E. vaginatum
Low
0
0
Intermediate
0
0
CO2
CH4
CH4
CH4
High
Low
Intermediate
High
Gas
CO2
CO2
Water table E. angustifolium E. vaginatum
Low
0
0
Intermediate
0
0
CO2
CH4
CH4
CH4
High
Low
Intermediate
High
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
+°
0
0
0
S. fallax
0
0
0
0
0
0
S. fallax
0
0
0
0
0
0
S. fallax
0
0
0
0
0
0
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
H3
H5
H7
D20, D21, D23
Resumed basal respiration WPII
Design plot for the CO2 production
CO2 production (µmol.d-1.dm-3)
260
H3
240
220
200
Low
180
EA
Intermed.
160
EV
S
High
CT
140
H5
120
H7
WT
Species
Depth
Factors
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
D20, D21, D23
Resumed basal respiration WPII
High
CT
Intermed.
EA
0.1
0.2
0.3
H7
S
EV
Low
H5
0.0
CH4 production (umol.d-1.dm-3)
0.4
Design plot for the CH4 production
H3
WT
Species
Depth
Factors
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
WPII: Active type II methanotrophs (FISH) in
growing Sphagnum (H3)
5e+7
8e+6
FISH
Type II Methanotrophs (ind./g f.wt)
DAPI (ind./g f.wt)
6e+6
4e+6
2e+6
0e+0
Low
Interm.
4e+7
DAPI
3e+7
2e+7
1e+7
0e+0
High
Low
Interm.
Water level
Water level
D11, D14, D20
Methanotrophs / DAPI counts
0.20
FISH/DAPI
0.15
0.10
0.05
0.00
Low
Interm.
Water level
High
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
High
Litter decomposition experiment
August 2004 - November 2005
WP III
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
D16, D20
Litter mass-loss (% d.wt/d.wt)
90
80
Mean mass loss* (%)
70
60
50
40
30
20
10
0
Low
Interm.
Water level
High
EA
EV
Litter species
S
EA EV S
EA EV S
EA EV S
Low
Interm.
High
Litter species X water level
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
D20, D21, D23
In-situ surface fluxes (WPIII)
40
9
CO2
7
35
6
CH4
30
CH4 flux (µmol.d-1.m-2)
CO2 flux (mmol.d-1.m-2)
8
25
5
20
4
15
3
10
2
1
0
5
0
Low
Interm.
High
Low
Interm.
High
Water level
Water level
50
15
Low
Interm.
Litter species X Water level
High
20
0
Low
CT
EA
EV
S
10
CT
EA
EV
S
CT
EA
EV
S
-5
CT
EA
EV
S
0
30
CT
EA
EV
S
CH4 flux (µmol.d-1.m-2)
5
CT
EA
EV
S
CO2 flux (mmol.d-1.m-2)
40
10
Interm.
Litter species X Water level
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
High
D20, D21, D23
Litter type effect on CO2 and CH4 production
A. Effects of different litter types on CO2 and CH4 emissions and production at various
depths. In all cases C02 production is decreasing with depth
Gas
CO2
CO2
CO2
CO2
CO2
CH4
CH4
CH4
CH4
CH4
Depth
Surface emission
Litter respiration
Peat respiration at 7.5 cm
Peat respiration at 15 cm
Peat respiration at 35 cm
Surface emission
Litter respiration
Peat respiration at 7.5 cm
Peat respiration at 15 cm
Peat respiration at 35 cm
E. angustifolium
0
+
0
0
0
BDL
0
0
E. vaginatum
0
+
+
0
0
0
BDL
0
0
all together -
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
S. fallax
-°
++
0
0
0
0
BDL
+°
0
D20, D21, D23
Litter effect on basal respiration (WPIII)
B. Effects of different litter types on on CO2 and CH4 production and emissions at
various water levels. In all cases C02 production is decreasing and CH4
production to increase with decreasing water level.
Gas
CO2
Water table
Low
E. angustifolium E. vaginatum
0
0
CO2
Intermediate
0
0
0
CO2
High
+
+
0
CH4
Low
0
0
++
CH4
Intermediate
0
0
0
CH4
High
0
0
0
Gas
Water table
CO2
Low
0
0
0
CO2
Intermediate
0
+°
0
CO2
High
-
0
0
CH4
Low
0
0
0
CH4
Intermediate
0
0
0
CH4
High
0
0
0
Gas
Water table
CO2
Low
--
--
-°
CO2
Intermediate
0
0
0
CO2
High
0
0
0
CH4
CH4
CH4
Low
Intermediate
High
0
0
-0
0
0
0
E. angustifolium E. vaginatum
E. angustifolium E. vaginatum
S. fallax
0
H4
S. fallax
H5
S. fallax
H7
D20, D21, D23
Resumed basal respiration (WP III)
Design plot for CO2 production
600
Low
500
EV
Interm.
High
CT
S
EA
H5
400
CO2 production (umol.d-1.dm-3)
700
H3
H7
WT
Species
Depth
Factors
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
D20, D21, D23
Resumed basal respiration (WP III)
8
10
H7
High
2
4
6
CT
Interm.
EA EV
S
Low
0
CH4 production (umol.d-1.dm-3)
12
Design plot for CH4 production
H5
WT
Species
Factors
H3
Depth
D20, D21, D23
Resumed surface respiration WPIII
5
Low
CT
3
4
S
Interm.
EA
EV
2
CO2 production (mmol.d-1.m2)
6
Design plot for CO2 production
High
Water_level
Litter_species
Factors
D20, D21, D23
Resumed surface respiration WPII
30
32
High
26
28
S
EA
EV
CT
24
CH4 production (µmol.d-1.m2)
34
Design plot for CH4 production
Low
Intermed.
Water_level
Litter_species
Factors
WPIII: Active type II methanotrophs in
Sphagnum litter
2e+7
2e+6
2e+7
DAPI (ind./g f.wt)
Type II Methanotrophs (ind./g f.wt)
3e+6
2e+6
2e+6
1e+6
1e+7
5e+6
5e+5
0e+0
2e+7
Low
Interm.
0e+0
High
Water level
Low
Interm.
Water level
D11, D14, D20
Methanotrophs / DAPI counts
0.25
0.20
0.15
0.10
0.05
0.00
Low
Interm.
Water level
High
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
High
D11, D14, D16,
D20, D21, D23
Conclusions
•In a situation with low water level, the presence of any kind of litter
decreases the CO2 production at -35 cm.
•In a situation with low water level, the presence of any kind of litter
decreases the methane production at -35 cm.
•Under intermediate water level conditions Sphagnum litter
drastically decreased the in-situ methane flux.
•The Sphagnum litter turnover time is higher under intermediate
water level conditions.
•There are more methanotrophs where more methane is produced! ;-)
•The surface CO2 fluxes in WPIII are strongly positively correlated to
the basal respiration at -15 cm depth and negatively correlated to the
methanogenesis at -15 cm depth. And inversely!
•The surface CH4 fluxes are negatively correlated to the CO2
production at -7.5 cm depth.
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006
Achievements during 2005/06
Andy (A), Emanuela (Em)
•
•
•
•
•
•
•
•
•
•
•
Em: terminated the surface gas flux measurements (NEE, Rtot, PG) at la
Chuax-d’Abel.
A&Em: surface methane fluxes Chaux-d’Abel during 2005.
FISH hybridisation for WPI - methodological improvement and counting of
methanogens and eubacteria.
Em: finished her master’s research and graduated in May 2006.
A+all: WPII sampling and dispatching in July 2005.
A&Em: WPIII surface fluxes, harvesting, sampling, dispatching, incubations
in autumn 2005.
A: WPII basal respiration for Baupt samples (monovette).
A: re-analysed delta 13C-CO2 and delta 13C-CH4 of the surface samples
using a supplementary cryogenic step to improve accuracy for methane.
A:WPIII surface samples basal respiration for the short term decomposition
experiment.
A: recounting whole community in WPI with inverted microscopic (total 18
from the 27 samples.
A&Em: WPII (FR): basal respiration (monovette) and FISH hybridisations for
methanotrophs.
A.Siegenthaler, RECIPE meeting Aberdeen 29-31 May 2006