Agriculture Reference
In-Depth Information
and the nitrogen content of each type of manure. The amount of chemical
nitrogen fertilizer applied was obtained by subtracting the organic nitro-
gen from the total required nitrogen. Crop specifi c nitrogen fertilizer ap-
plication recommendations [27] were integrated over the respective LCC
crop areas to derive the total nitrogen in the LCC. The amount of chemi-
cal nitrogen was adjusted to the amount of fertilizer actually sold in each
region [28]. This adjustment factor was calculated by comparing the total
recommended amount of nitrogen calculated and assumed to be applied
within each province to the total nitrogen fertilizer purchased in the same
province [4,14-16].
Although smaller in magnitude than agricultural methane and nitrous
oxide emissions, farm energy is an essential part of the sector's GHG
emissions budget [29,30]. A combination of farm statistics and agricultur-
al engineering coeffi cients were used to estimate the fossil CO
2
emissions
from the fossil fuel for farm fi eldwork [31,32]. The energy and fossil CO
2
emissions associated with on farm transport, farm use of electricity and
heating fuel and the indirect fossil energy to manufacture and transport
farm machinery and chemical fertilizer to the farm were also included
[30,33,34].
6.2.1.4 THE SOIL CARBON STOCK
In previous commodity specific applications of the LCC methodology,
CO
2
emissions from soil carbon were not considered because each live-
stock system was treated in isolation with little change in overall land
use or management. ULICEES treats soil carbon as an exhaustible storage
term, including changes in soil organic carbon (SOC) between different
land-use management systems in a similar manner as IPCC GHG account-
ing methodology [22], whereby a land-use/management system that is in
equilibrium is converted to a new land-use/management system and is as-
sumed to reach a new equilibrium within a time frame. Some forage fields
that are in rotation with annual crops may not be at equilibrium. For these
cases, additional atmospheric CO
2
which would have been sequestered if
those forage areas in rotation had been given time to come to equilibrium,
along with the sequestered soil carbon. Including that lost sequestration
