JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

ESTIMATION OF N2O EMISSIONS FROM

CROP RESIDUES

USING IPCC TIER 1a AND TIER 1b METHODS

Adrian Leip

Joint Research Centre

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

IPCC METHODOLOGY FOR DIRECT EMISSIONS OF N2O FROM AGRICULTURAL SOILS

IPCC APPROACH TIER 1a:

BURNR

NCRBFBFNCR00CR

Frac1Frac1

FracCropFracCrop2F

Product FracR FracN

Non N-Fixing 0.45 0.015

N-Fixing 0.45 0.030

converts CropO and CropBF to total aboveground crop

residueand product.

fraction of crop residue that is removed from the field as crop (kg

N/kg crop-N) (IPCC,1997)

fraction of total aboveground crop biomass that is removed from the

field ascrop.’ (IPCC 2000)

estimates fraction of nitrogen present in the crop

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

crop specificIPCC APPROACH TIER 1b:

jjjj

iiii

jjj

j

j

iii

ii

FODCRCNSTCRFUELBURNj

FODCRCNSTCRFUELBURNi

j jNCRBFDMBF

BFBF

i iNCRODMO

OOCR

FracFracFracFracx

FracFracFracFracx

x1FracFracCropRes

Crop

x1FracFracCropRes

CropF

explicit included

replaces 2*(1-FracR)

other uses expanded

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

Product FracR FracDM FracC FracN

Wheat 1.3 0.82-0.88 0.4853 0.28%  

Barley 1.2 0.82-0.88 0.4567 0.43%  

Maize 1.0 0.70-0.86 0.4709 0.81%  

Oats 1.3 0.92 0.70%  

Rye 1.6 0.90 0.48%  

Rice 1.4 0.82-0.88 0.4144 0.67%  

Millet 1.4 0.85-0.92 0.70%  

Sorghum 1.4 0.91 1.08%  

Peas 1.5 0.87 1.42%  

Beans 2.1 0.82-0.89  

Soybean 2.1 0.84-0.89 2.30%  

Potatoes 0.4 0.4226 1.10%  

Feedbeet 0.3 0.4072 2.28%  

Table 4.16 - IPCC 2001

Tier 1a

Non N-Fixing 1.5%

N-Fixing 3.0%

If a default r

esidue nitr

ogen content is

needed for a

crop ty

pe for

which a value is

not provided in

Table 4.16, the non-cr

op specifi

c

default values f

or N-fixing and Non-N

-fixing crops t

hat are lis

ted in

Table 4-19 of the Reference

Manual o

f the IP

CC Guidelines c

an be

used (0

.03 and 0.015 kg N/kg dry matte

r, resp

ectively). (

IPCC, 2000)

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

?→ Unit of factor 2: kg dry total biomass / kg dry biomass in crop

product

→ Unit of FracR: kg N in crop residue / kg N dry total biomass

The IPCC Guidelines present a default value for FracR of 0.45 that is not consistent with the default value

presented foraboveground crop residue and

product. If FracR = 0.45, then 55% of the residue plus crop product mass

equals residue.However, if residue plus crop product

mass equals 2 times the crop product, then 50% of the residue plus

crop product massequals residue.

(IPCC 2000, p. 4.59)

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

Nitrogen fractions [kg N (kg dry matter)-1]

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

EMISSIONS OF N2O FROM CROP RESIDUES[Gg N2O]

BE DK DE GR ES FR IE IT NL AT PT SE FI UK

1)The German values are calculated with national data expressed in kg N/ha of crop produced, and therefore not directly comparable with the other values2)Spain uses a methodology developed by allocating the total amount of nitrogen extracted by the plants (calculated estimated in particular for the plant fractions burnt or buried into the soil (Ferreiro, 2003)

Tier 1a (default values)

2.8 3.5 23.1 2.9 8.4 29.2 1.1 11.5 4.4 2.3 1.1 2.3 1.5 9.6

Tier 1b (default values)

0.5 1.2 9.6 1.3 3.9 12.2 0.3 3.9 0.6 0.9 0.3 0.8 0.6 3.5

CRF 2002

2.4 1.0 3.91) 0.5 2.12) 9.4 0.4 2.8 NE 0.5 0.3 1.3 0.5 8.7

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

RECOMMENDATIONS (i)

→ The default values presented in Tier 1a and Tier 1b

methods yield large discrepancies in the emission

estimates

Default values for the nitrogen fraction in crop residues

need to be streamlined.

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

RECOMMENDATIONS (ii)

→ The list of default parameter for calculating N2O

emissions from crop residues does not reflect the

complete cropping pattern in many countries.

(a) MS are encouraged to deliver a list of important crops

for which default values should be proposed

(b) The guidelines should expand the list of default

parameter for N2O emissions from crop residues.

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

RECOMMENDATIONS (iii)

→ National parameters are

important for assuring high

quality of the estimate for N2O

emissions from crop residues.

They are usually reported in the

National Inventory Reports.

A link / the use of background Table4.F would ensure a

more transparent reporting of N2O emissions from crop

residues.

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

parenthesis: Countries which have reported burning of crop residues …

Country FracBURN FracLEACH FracNCRBF FracNCRO FracR

Austria 1% 30% 0.5% 1.5% 34.1%

Greece 10% 30% 0.0% 0.0% 0.0%

Italy 10% 30% 3.0% 1.5% 45.0%

Portugal 10% 27% 1.3% 2.3% 79.9%

Norway 15% 18% NE NE NE

Estonia 90% 30% 1.5% 3.0% 55.0%

Hungary 9% 30% 3.0% 1.5% 45.0%

Latvia 10% 30% 1.5% 3.0% 45.0%

Bulgaria 10% 10% 3.0% 1.5% 10.0%

Croatia 10% 30% 1.5% 3.0% 45.0%

Romania 25% 30% 1.5% 3.0% 45.0%

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

RECOMMENDATIONS (iv)

→ Intercrops are common in certain regions of Europe and

affect largely timing and rate of nitrogen input.

The use of intercrops should be reflected in the

guidelines.

JRC-AL – Expert Meeting on Cat.4D reporting – 21/22.10.2004

THANK YOU FOR YOUR ATTENTION !