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Congo, Mozambique and Tanzania) will increase the demand
for livestock products, intensifying and expanding agriculture
to still largely unexploited areas, thereby resulting in higher
GHG emissions (Smith et al., 2007a). In East Asia, with a 4 and
12 times increase of milk and meat production, respectively,
from 1961 to 2004 (Anonymous, 2006c) and its projected
continued increase in consumptions, the GHG emissions are
expected to increase 86% and 153%, respectively, from enteric
fermentation and manure management, during 1990 to 2020
(Anonymous, 2006a). In a pursuit to ensure food security for its
teeming population, South Asia will be using more and more
nitrogenous fertiliser and manure, thereby increasing its GHG
emission (Anonymous, 2006a).
Deforestation of cropland and grassland in the Latin America
and Caribbean resulted in increased emissions of GHG, mainly
CO
2
and N
2
O (Anonymous, 2006c). N
2
O emissions have sig-
nificantly reduced in the countries of Central and Eastern
Europe, the Caucasus and Central Asia for their decreased use
of nitrogenous fertilisers since 1990. However, driven by favour-
able economic conditions in these countries, the use of nitrog-
enous fertilisers may shoot up again, which will result in 32%
increase of N
2
O emissions from soils by 2020 (Anonymous,
2006c). Non-CO
2
GHG emissions increased consistently from
the agricultural sector between 1990 and 2020 in OECD North
America and OECD Pacific with an 18% and 21% increase,
respectively. These emissions were from manure manage-
ment and N
2
O from soils. In Oceania, emission increased due
to exponential increases of nitrogenous fertiliser use, while in
North America it increased due to management of manure from
cattle, poultry and swine production along with manure applica-
tion to soils. Fortunately, CO
2
emission from land conversion
has been reduced in both these regions having active vegeta-
tion policies restricting further clearing (Anonymous, 2006a).
The only region in the globe with decreased projection of GHG
emissions from agriculture till 2020 is Western Europe due to its
adoption of climate-specific and environmental policies along
with economic constraints on agriculture (Anonymous, 2006a).
1.3
Global agricultural land use change
and implication
Out of the total agricultural land globally in 2002 (5023 Mha),
pasture has 3488 Mha or 69% dominated, followed by cropland
