ucc opportunities for carbon sequestration in irish grasslands vesna jakši ć supervisors: g....

UCCUCC

Opportunities for Carbon Sequestration in Irish

Grasslands

Vesna Jakšić

Supervisors: G. Kiely, University College Cork

O. Carton, D.Fay, Johnstown Castle

Dublin, 20/11/2003

UCCUCC

Why study atmosphere Carbon Dioxide ?

The Kyoto Protocol for Ireland requires that emissions of GHG must be no more than 13% above the 1990 levels

As of 2001, emissions are 31% greater than the 1990 levels (EPA)

By 2008 – 2012 the “business as usual” scenario forecast (produced in 2000 based on 1998 data) is that emissions may be more than 37% greater than the 1990 levels (NCCS)

Agricultural is responsible for about 27% (soils 5.5%) in 2001 of emission (EPA)

Opportunities for Carbon Sequestration in Irish Grasslands

UCCUCC

Question ?


Are agricultural soils sources or sinks for carbon ?

Air

Soil

Source Sink

C sequestrationC sequestration

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Budget of Carbon for a farm

NEE – (A + B + C+…) = Csoil

NEE = Net Ecosystem exchange in T of C/ha

NEE = GPP – Rh – Ra

A, B, C… = carbon leaving the farm

(in milk, in meat, in enteric fermentation etc.)

CCsoil soil = the carbon fixed to the soil = the carbon fixed to the soil

or lost to the atmosphere?or lost to the atmosphere?


UCCUCC

Objectives of project

Measure and model the CO2 flux at grasslands in

Dripsey (Cork) and Johnstown Castle (Wexford)

Investigate seasonal, annual and interannual

fluxes

Estimate the carbon budget at farm scale and so

determine if the soils are sinks or sources of

carbon


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Sites

Wind Rose Downwind direction is SW

Cork grassland – Dripsey

Elevation ~ 190masl

Annual rainfall ~ 1450mm


red dots ↔ site areas

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NEE – Eddy Covariance System


Rain gauge

Temperature and relative humidity probes at 3m

Perimeter for soil moisture, soil temperature and soil heat flux probes

The automatic weather station– tower in full height

Sonic anemometerNetradiometer

LICOR H2O/CO2

sensor

LICOR electronics box

Top of the tower with instruments

UCCUCC

Eddy Covariance


Hz(m/sec)@10

Hz10@(mol/m 2

speed windvertical of nfluctuatio the

CO of nfluctuatiodensity the

time averaging minute 30

offlux the

)3

w'

ρ'

ρ'w'- F

CO F

c

c c

2 c

Sonic anemometer

LI-7500 Open Path CO2/H2O gas analyser

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Footprint area


Estimated footprint

N

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CO2 flux measurements

July 2001 to Jun 2003 (the results for 24 months)

Nitrogen in chemical fertilizer was applied at the

rate of 190kgN/ha and N in slurry approximately

90kgN/ha for the year 2002

The site is intensive cattle grassland (Livestock

density 2.2 LU/ha) with mix of grazing and silage


UCCUCC

-40

-30

-20

-10

0

10

20

Flu

x o

f C

O2

[ m

ol/m

2 .sec

]

Measured

19/08 20/08 21/08

August 2002

Net Photosynthesis

Net Respiration

Raw CO2 flux data @ 30 minute intervals


UCCUCC

CO2 flux and soil moisture


SIN

K

S

OU

RC

E

Soil porosity48%

jul aug sep oct nov dec jan feb mar apr may jun jul aug sep oct nov dec jan feb mar apr may jun-400

-300

-200

-100

0

100

200

[g/m

2 ]

jul aug sep oct nov dec jan feb mar apr may jun jul aug sep oct nov dec jan feb mar apr may jun0.2

0.25

0.3

0.35

0.4

0.45

0.5

[m3 /m

3 ]

CO2 flux per month

soil moisture at root zone

2001 2002 2003

UCCUCC

jul augsepoct novdec jan febmar aprmayjun jul augsepoct novdec jan febmar aprmayjun-6

-5.5

-5

-4.5

-4

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

0.5

[T o

f C

/ha]

-22

-20

-18

-16

-14

-12

-10

-8

-6

-4

-2

0

[T o

f C

O 2 /h

a]

2001 2002 2003

-3.7

1 2

-2.2

(13.6)

(8.1)

Cumulative uptake T Carbon/ha


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Cumulative uptake T Carbon/ha

jan feb mar apr may jun jul aug sep oct nov dec-4

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

0.5

[T o

f C

/ha]

-14

-12

-10

-8

-6

-4

-2

0

[T o

f C

O2/h

a]

9.2

Year 2002


UCCUCC

Some NEE values

location Type of landNEE

[T of C/ha.yr]

1 Duke, US Loblolly pine forest 5.7 to 7.9

2 Mandan, US Native prairie 0.6 to 0.9

3 Woodward, US Plain prairie -0.2 to 1.8

4 Temple, US Mixed-grass prairie 2.2 to 7.7

5 Ottawa, Canada Bog peatland 0.5 to 0.9

6 Cork, Ireland Perennial ryegrass pasture 2.2 to 3.7


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Carbon leaving the farm


A. Carbon in milk [t.C/ha.yr.] average production 7500L/ha. density φ = 1.03kg/L carbon in milk = 4.5%

310100

5.403.17500 C

CA = 0.35 T.C/ha.

B. Carbon in meat [t.C/ha.yr.] ~18% of live weight 1LU = 520kg pasture dry matter per year Stocking Density for Dripsey = 2.2LU/ha Assume that 1/3 of animals leave farm for

the meat factory

CB ≈ 0.1 T.C/ha

31031

10018

5202.2 C

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Carbon leaving the farm


C. Carbon in CH4 respired from animal and CH4 from manure for full year

100kg CH4 from animal 15kg CH4 from manure Stocking Density for Dripsey = 2.2LU/ha CC = 0.20T.C/ha.

D. Carbon as CO2 from respiring animal indoors for 4 months of year

Diet = 10kgDM/day/LU DM = 45%Carbon Assume 40% respire CD = 0.45 T.C/ha

3101612

2.2151 C

31010040

124

2.210045

36510 C

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Carbon BudgetCO2

Net Ecosystem ExchangeNEE

-2.5 T.C/ha/yr

AtmosphereAtmosphere

CanopyCanopy C as DOC/DIC in stream+0.1 T.C/ha/yr

C as CH4 from yard manure / slurry +0.1 T.C/ha/yr

C as CO2 from respiring animal indoors for 4 months of year

+0.45 T.C/ha/yrC in milk export+0.35 T.C/ha/yr

C in meat export+0.1 T.C/ha/yr

C as CH4 from animal +0.2 T.C/ha/yr

SoilSoilSoil Sequestration

-1.2 T.C/ha/yr


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Conclusions


For 8 months (Mar to Oct) the site is a sink of carbon

Interannual variability of NEE is significant

(2.2 to 3.7 T of C/ha.yr) – need long term measurements

Preliminary results – carbon sequestration for 2002

at Cork site is 1.21.2 T of C/ha.yr (forestry 3 to 6 T of C/ha)

Preliminary results suggest that there may be

opportunities for Carbon sequestration in grassland soils

UCCUCC

Acknowledgements

Environmental Protection Agency

Teagasc Walsh Fellowship Programme

O. Carton and D. Fay, Environment and Land

Use Department Teagasc Johnstown Castle

G. Kiely, University College Cork


ucc opportunities for carbon sequestration in irish grasslands vesna jakši ć supervisors: g....

Documents

carbon sequestration

ucc opportunities

ucc budget of carbon

carbon budget

soil moisture opportunities

ucc question

instruments slide

silage opportunities