CONCLUSIONS
The processes of carbon and nitrogen
mineralization leading to N2O and CO2
emissions
from soils are affected by the variations of moisture,
temperature, fertilizer application and organic carbon
availability. Moreover, for CO2
and N2O production,
it can conclude that the variation between soils at
different periods of emission was accounted for by
differencesin organic carbon availability. Gravimetric
water content (5%) appeared to be effective in
reducing CO2
and N2O emissions in both soils.
However, NO3
-
content was significantly higher in
arable soils than in grass soils. Thus, it is concluded
that long drying and rewetting can increase NH4
+ but
not NO3
-
. High doses of nitrogen fertilizer result in
low nitrogen utilization by denitrifies and a high risk
of water contamination by nitrates leading to further
research on the judicious use of nitrogen on wheat
crops. Grassland soils can be nitrogen retaining if not
frequently moistened. As far as control treatment is
concerned, it can be argued that the soils under
continuous moist conditions, or frequently rewetted,
can experience increased nitrification thereb