The GHG emissions from Agriculture are released as a result of the activities for production and processing of agricultural goods, soil fertilization and manure management.
All the emissions related to combustion of fuels for energy are reported in sub-sector Agriculture and Forestry in the Energy sector, and the emissions from agricultural machines - in group Other Transportation, sub-sector Transport of the Energy sector.
The GHG process emissions in Agriculture are divided into the following sub-sector:
- Enteric Fermentation from domestic livestock;
- Manure Management;
- Rice Cultivation;
- Agricultural Soils;
- Field Burning of Agricultural Residues.
The processes and activities of the sub-sectors (categories) enlisted above, are mainly sources of CH4 and N2O emissions.
In field burning of agricultural residues are emitted certain quantities of GHG precursors, CO and NOx.
The larges N2O emissions source is the Agricultural Soils sub-sector.
In this sub-sector the emissions from the agricultural soils are a result from soil fertilization with synthetic and natural (animal) fertilizers, decomposition of vegetal residues, cultivation of marshy soils (type histosols), and the indirect emissions from ammonia and nitrous oxides decomposed after soil fertilization.
The parameters and emission factors for estimating the GHG emissions from the sector are from the IPCC Guidelines. Expert judgments on local manure management practices, on CH4 emissions from enteric fermentation and manure management were used for some parameters.
In Figure 6.1 the CH4 emission trend in the separate categories is presented.
As seen in Figure 6.1 the emissions from enteric fermentation have the largest portion of the overall CH4 emissions in the sector - over 70 % during the period 1988 - the year 2002. The emissions from manure management are about 23 - 27 %. The emissions from the two remaining sub-sectors are by one magnitude lower than those of the above ones.
The N2O emissions from the sector are also large in volume. The most significant portion is released from agricultural soils. For the year 2002 it constituted 86 %, and for the entire period (1988 - the year 2002) this share remains in the range of 83 - 87 %. The N2O emissions from manure management and field burning of agricultural residues are one magnitude lower and they both total up to 13 - 17 % of the overall N2O emissions from this sector.
As a general the N2O emissions from the sector (expressed in CO2 Eq.) are about 33 % higher than the CH4 emissions (expressed in CO2 Eq.).
