Transcript GHG Fluxes from Terrestrial Ecosystems

Hydrology, Micrometeorology and Climate Change
GHG fluxes from Terrestrial Ecosystems
- peatlands, grasslands and forestry
Nelius Foley, Matteo Sottocornola, Paul Leahy, Valerie Rondeau,
Ger Kiely
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University College Cork, Ireland
Environmental Research Institute
Ecosystem Fluxes & Climate Change
Environmental
Fluid Mechanics
Hydrology
Water Fluxes
e.g. Streamflow;
Evapouration
Ecosystem
Functioning
Ecology
SPECIES
LOSS
Climate Change
EUTROPHICATION
Water
Chemistry
River Water
Quality- Nutrients
(N & P)
Soil HydrologySoil Carbon stocks
WARMING
Soil Hydrology Soil Physics
Ecosystem
GHG Fluxes
CO2, N2O, CH4
Atmospheric Physics
MULTI-DISCIPLINARY RESEARCH
University College Cork, Ireland
Environmental Research Institute
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Some Past & Current Projects
1. EUTROPHICATION (2002-2005) – Phosphorus loss from soil to water
2. CELTICFLUX (2002-2013)– Measurement/modelling of GHG fluxes
3. Flood Studies Update – Flood Event Analysis
4. Flood Warning Web – River Blackwater Live Flood Warning System
5. CarboEurope & NitroEurope – European Terrestrial Carbon and Nitrogen Balance
6. N2O grass – N2O emissions from Irish grasslands
7. Hydrological Extremes – increasing extremes in precipitation and temperature
8. Soils Projects:
a. SoilC – Measurement and Modelling of Soil Carbon Stocks and Stock Changes in Irish Soils
b. ForestC – Soil carbon stock changes and greenhouse gas fluxes in Irish forests
c. SoilH – Interactions of soil hydrology, land use and climate change and impacts on soil quality
d. GrassC – Investigation of Carbon Sequestration potential in Grassland Soils
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University College Cork, Ireland
Environmental Research Institute
Hydromet
• Field experiments in different ecosystems (soils
+biomass) – throughout Ireland
• Data analysis and modelling – using
empirical and process based models
• Model climate change scenarios –e.g. effect of climate
warming on Ecosystem productivity/respiration
Our laboratories are Irish ecosystems and
catchments – grasslands, peatlands and forests.
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University College Cork, Ireland
Environmental Research Institute
GHG Fluxes
• Grasslands
Terrestrial Ecosystems
• Peatlands
• Forestry
GHG Fluxes: CO2; N2O; CH4
Atmosphere
Sign convention
SINK
-
+
SOURCE
Land surface
Land – Atmosphere interaction
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Sink or Source of Carbon
• CARBON SINK – means the ecosystem (soils + vegetation) removes
carbon (as CO2) from the atmosphere
– computed over a timescale from 10 Hz to years
• CARBON SOURCE – means the ecosystem returns (emits) carbon to
the atmosphere
Annual NEE = Net Ecosystem Exchange
= CO2 Uptake (mostly but not always)
Respiration
night
NEE = PG – Rtot
PG = Gross Photosynthesis
Rtot = Total Respiration (soil + plant)
day
0
6
12
CO2
flux
day
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Net
Photosynthesis
24
30
36
42
48
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Atmosphere
Peatlands
Sink for CO2 (-)
-CO2
+CH4
+CH4
Forestry
-CO2
-CO2
+N2O
Source for N2O(+)
Source for CH4 (+)
Grasslands
+N2O
Animals
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UCC GHG flux sites
Since 2002 with
EPA/EU funding
Chamber CO2
Glencar,
Kerry.
Chamber CH4
Peatland
EC CO2
EC N2O
Modelling CO2
Dripsey, Cork.
Modelling N2O
Grassland and forestry
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Global FLUXNET sites
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Eddy Covariance CO2 Flux measurements
We sample the turbulent motion
between the biosphere and the
atmosphere to determine the net
difference of moving material (CO2,
N2O, CH4).
We sample the 3D wind speed and
GHG concentrations at 10Hz and
then averaged over 30 min
LI-7500 Open
Path
CO2/H2O gas
analyser
3D-Sonic
anemometer
Fc  w' ρc '
w' = fluctuation of the vertical wind
speed @ 10 Hz
ρc' = density fluctuation of CO2 @ 10 Hz
Fc = averaged over 30 minutes
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Field Instrumentation
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University College Cork, Ireland
Environmental Research Institute
Dripsey – Monthly Uptake – (NEE – Net Ecosystem Exchange)
Managed grassland - 3 farms – mix of grazing + silage fields
g CO2 m-2
100
Source- Emissions
200
-2
NEE (g C m )
50
0
-50
-100
200
2003
2004
2005
2006
2008
2009
Sink -Uptake
-150
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
400
Dec
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Dripsey Grassland CO2 fluxes 2002-2006
Growing
Season
Range or
interannual
variability
2 to 3 T C/ha.yr
Silage cutting
and/or grazing
or
7 to 11 T
CO2/ha.yr
1st May
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PEATLAND: monthly CO2 flux
EMISSIONS
UPTAKE
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Sottocornola & Kiely, 2010. Agricultural and Forest Meteotology
PEATLAND: cumulative CO2 flux
Interannual
variability
0.16
TC/ha.yr
To
0.95
TC/ha.yr
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Land Use Change (LUC)
Grassland to Broadleaf Forest – CO2 Exchange
Grassland tower – forest sector, 2003 - 2009
Planting year
-100 g C m-2 y-1
Recovery years
~ -150 to -350
g C m-2 y-1
Grassland
-500 g C m-2 y-1
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Indicative annual biomass growth
>1000 mm
~ 500 mm
~0.25 mm
Peatland
(natural)
Grassland
(managed)
Forestry
(managed)
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GHG Fluxes - Position
• Today, we have the technology to continuously measure and
quantify the GHG fluxes from the different ecosystems
• Globally, there are ~ 300 research EC sites with 3/4 Irish sites
• ICOS – International Carbon Observation System aims to put GHG
fluxes on a similar footing to meteorological synoptic stations with
real time publicly accessible data
We acknowledge the EPA for their continuous support,
without which this work would not be possible.
Thank You
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