35 / 104
35
LOSS OF CROPLAND AREA
There has been a growing trend all over the world in converting
cropland to other uses due to increasing urbanization, indus-
trialization, energy demand and population growth. China, for
example, lost more than 14.5 million ha of arable land between
1979 and 1995 (ICIMOD, 2008).
Current projections suggest that an additional 120 million ha
– an area twice the size of France or one-third that of India – will
be needed to support the traditional growth in food production
by 2030, mainly in developing countries (FAO, 2003), without
considering the compensation required for certain losses. The
demand for irrigated land is projected to increase by 56% in Sub-
Saharan Africa (from4.5 to 7 million ha), and rainfed land by 40%
(from 150 to 210million ha) in order to meet the demand, without
considering ecosystem services losses and setbacks in yields and
available cropland (FAO, 2003; 2006). Increases in available crop-
land may be possible in Latin America through the conversion of
rainforests (Figure 13), which in turnwill accelerate climate change
and biodiversity losses, causing feedback loops that may hinder
the projected increases in crop yields. The potential for increases
is more questionable in large parts of sub-Saharan Africa due to
political, socio-economic and environmental constraints. In Asia,
nearly 95% of the potential cropland has already been utilized
(FAO, 2003; 2006). Even if such increases are not restricted by
other land use and the protection of tropical rainforests, changes
in the proportion of non-food crops to food crops may have even
greater impacts on the available cropland for food production.
Area (million ha)
0
200
400
600
800
1000
Industrial
countries
Transition
countries
East Asia
Sub-Saharan
Africa
South Asia
Latin America
and Caribbean
Near East
and
North Africa
Land suitable for
rainfed crops
Arable land
1997-1999
Figure 13: Theoretical potential for cropland expansion, irre-
spective of conservation, water and other environmental issues.
(Source: FAO, 2003).
The interaction among these variables is very complex, and pro-
viding quantitative estimates of their significance is nearly impos-
sible. The key variables are not currently accounted for in most
models and scenarios of food production (FAO, 2003; 2006).
In this chapter we attempt to provide estimates of possible rang-
es of future impacts of environmental degradation on yield and
available cropland, based on the best knowledge available, peer-
reviewed studies and expert judgment. We will not, however, at-
tempt to quantify the full value of ecosystem services from the
environment, which entail complex interactions and processes.
The estimates given here are of possible ranges based on some
current projections of the degree of environmental degradation.
The FAO has provided estimates of cropland and yield increas-
es necessary to meet future demand for food, without fully con-
sidering the role of environmental degradation and losses of
ecosystem services. Hence, the following material provides an
insight into the possible losses (and the compensation needed)
in food production as a result of environmental degradation, to
support other UN agencies in further improving estimates of
demand and production in a changing world.