Agriculture Reference
In-Depth Information
people today to over 9.5 billion in 2050. In
addition, economic progress, notably in the
emerging countries, translates into increased
demand for food and other products that the
land must deliver (FAO, 2011). Feeding the
growingworldpopulationmayrequirean
additional 2.7-4.9 Mha, biofuel production
1.5-3.9Mha,urbanization1.6-3.3Mha,in-
dustrialforestry1.9-3.6Mhaandprotected
areas 0.9-2.7 Mha year
-
1
,
whereas land deg-
radation will render ≈
1-
2.9 Mha year
-
1
un-
suitable for cultivation. With an additional
total land demand of 9.5-26.4 Mha year
-
1
,
the current land reserve (i.e. non-forested,
non-protected and populated with <
25
per-
sons km
-2
) could be exhausted as early as in
the late 2020s, and at the latest by 2050
(Lambin and Meyfroidt, 2011). This means
that intensive land uses will continue ex-
panding into areas where SOC stocks are
less resilient, soil conditions are marginal
for agriculture and lands are prone to deg-
radation. Semi-arid savannahs and grass-
lands, tropical rainforests and peatlands
will all experience tremendous pressure to
be further converted to arable land (Victoria
et al
., 2012).
The future of SOC will ultimately de-
pend on
how
conversionandconsequent
land management will take place, whether
soil carbon will continue to be mined for short-
term gains, but with long-term detriment.
The alternative action is to implement
land management that will conserve and
enhance soil carbon. This will be essential
to carry Earth's land-use practice through
what could be some of the deepest resource
crises of the 21st century and to establish a
legacy of land resources that will sustain fu-
ture generations thereafter.
References
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