Scientific Papers Series A. Agronomy

Activity data
Activity data comes from the Romanian
Institute for Statistics: annual amount of
synthetic fertiliser nitrogen applied to soils;
number of each livestock category; surfaces
cultivated annualy with different crop
categories; crop productions. The animal
categories and sub-categories were grouped
according to the main production system, and
follow international inventory formats. The
main categories were: cattle, buffaloes, pigs,
sheep, goats, mules and donkeys, horses and
poultry. The classes of crops were defined
based on Romanian crop production within the
main production system, and follow
international inventory formats and comprise:
cereals, legumes, textil plants, oil plants,
industrial plants, medicinal and aromatic plants,
vegetables, forrage plants. Nitrogen excretion
rates were calculated for each sub-category.
Emissions factors were used as IPCC (1996a)
default values as any country-specific
emissions factors were developed since
Romania ratified the Kyoto Protocol in 2001
(EF1 = 0.0125 kg N-N 2 O/kg N; EF4 = 0.01 kg
N 2 O per kg NH 3 and NO x ; EF5 = 0.025 kg N 2 O
per kg N).
For different parameters used for emissions
estimation, default values (IPCC 1996a) or
assumed values by the experts were used
(FracGASF = 0.1 kg NH 3 -N + NO x -N/kg;
FracGASM = 0.2 kg NH 3 -N + NO x -N/kg). For
the parameters FracFUEL-AM, FracFEED-
AM, and FracCNST-AM experts assumed the
value “0” as no available source of national
official data. For ResBF/CropBF, FracDMi
and FracNCRBFi default values (IPCC 1996a)
were used as is presented below:
Parameter Peas Beans Soy bean Other
grain
legumes
Alfalfa for
green grass
Clover for
green grass
Other
perennial
legumes
Res BF /Crop BF 1.5 2.1 2.1 1.8 0 0 0
Frac DMi 0.87 0.82-0.89 0.84-0.89 0.85 0.85 0.85 0.85
average 0.85 average: 0.865
Frac NCRBFi 0.0142 0.03 0.0230 0.03 0.03 0.03 0.03
For ResOi/CropOi the IPCC default values
were used as for FracNCROi and
FracNCRBFj. For FracBURNi/j, Frac FUEL-
Cri/j, FracCNST-Cri/j and FracFODi/j experts
assumed different values in relation with the
different type of crops and with the habits of
the rural population in particular.
The manure quantity is calculated using the
prototype parameters for different types of
animals in the Eastern Europe region, given in
the IPCC Guidelines (2000).
RESULTS AND DISCUSSIONS
The values of the total, direct and indirect
estimated emissions are presented in the Table
1a, Table 1b and Figure 1. The total soil
emissions decreased from 46.29 Gg N-N 2 O in
1989 to 20.18 Gg N-N 2 O in 2000. Between
2001 and 2010, only in 2004 there was an
important growth of N 2 O emissions, but not
more than 24.42 Gg N-N 2 O respectively. This
decrease of total soil emissions of N-N 2 O is
due especialy to the dissolution of state
agricultural entreprises and agricultural
cooperatives but also to the inability of small
farmers to manage their own crops and farms.
In the same time, the decrease of N 2 O soil
emissions it is also a consequence of the some
other reasons such as: the decrease of cultivated
area (Figure 2), the decrease of the quantities of
mineral fertilizers used per hectare (Table 2), as
it was observed by Hera (2009) and, not in the
end, the small quantities of organic fertilizers
that were used.
From the total soil estimated emissions, the
direct one are representatives in relation with
the indirect emissions (Figure 3) during all the
period. So as, the direct emissions represented
more than 60% from the total soil emissions
with a biggest value in 1999 (68.37%) and the
indirect one represented more than 30%, the
biggest have been noted in 2007 (38.44 %).
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