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Food loss and waste in agro-ecosystems
Agriculture takes up 37.6 per cent of the world’s land area, producing food, forage, bio-energy and
pharmaceuticals. Against the backdrop of an increasing population, the food production capacity
of agro-ecosystems is under threat from climate change, land degradation and loss of biodiversity.
Soil erosion alone is blamed for losses in potential grain yield of as much as 5 million tonnes per
year, an amount that is enough to meet the annual food calorie needs of 24 million people. A
further 3 million tonnes of grain is lost through salinization of croplands, which could potentially
feed 14.3 million people over a year. The losses in potential food production from agriculture due
to environmental degradation are in addition to the 1.3 billion tonnes of food that are produced
but never consumed every year. About 1.4 billion hectares of land are used to produce food that
is either lost or wasted. At the same time the rates of increase in food production are falling, a
trend that shows the planet is reaching its full potential for food production through conventional
agricultural practices. A shift towards ecosystem approaches that can maintain or enhance
the quality of agro-ecosystems could reverse the trend and significantly increase overall food
production in a sustainable manner.
An estimated 37.6 per cent of the world’s total land area is used
for agriculture (FAO 2013a), and this ratio continues to expand.
Crop and grazing lands, the main agricultural ecosystems, are
a major source of food. In addition, agriculture also provides
forage, bioenergy and pharmaceuticals (Power 2010). As
much as 1.5 billion hectares, constituting 12 per cent of the
world’s land area, is used for arable and permanent crop
production. Considerable amounts of more land are suitable
for crop production, but these are covered in forests, used
for settlements or protected for environmental conservation
(FAO 2013a). According to the FAO (2009), agricultural systems
include agro-forestry, pastoralism, crop monocultures, grazing
systems, mixed cropping, paddy rice farms, perennial orchards,
shifting cultivation, small home gardens and plantations of oil
palm, coffee, cacao and sugarcane.
Food production through agriculture depends on services
provided by natural ecosystems, including biological pest
control, hydrological services, maintenance of soil structure
and fertility, nutrient cycling and pollination (Power 2010).
At the same time, agriculture also produces ecosystem
services and disservices, depending on management
practices. Ecosystem services from agriculture include
carbon sequestration, disease control, regulation of soil and
water quality, cultural services and support for biodiversity,
while disservices include greenhouse gas emissions, loss
of wildlife habitat, nutrient runoff, pesticide poisoning and
sedimentation of waterways (Power 2010). Since the food
provisioning role of agriculture is dependent on and has
impacts on other ecosystems, there is a clear connection
between agricultural ecosystems and other ecosystems such
as mountain, forest and freshwater.
Good management practices can reduce the negative
impacts of agriculture on ecosystems, while at the same time
maintaining or increasing food production (Power 2010). Food
provisioning can therefore be optimized through appropriate
management practices targeted at supporting and regulating
ecosystem services, as well by reducing ecosystem disservices
(Zhang
et al.
2007).
Food production trends
As a result of population growth and changing consumption
patterns, the demand for food and production of food is
increasing. Cereals such as wheat, rice and maize provide
about two-thirds of all energy in human diets (Cassman 1999)
and are grown on about half of the world’s total harvested land
area (FAO 2013a).
The past 50 years have seen global crop production expand
threefold, with cereal production reaching 2.3 billion tonnes in
2012. Of this amount, about 1 billion tonnes was used for food
and 750 million tonnes for animal feed. About two-thirds of the
remaining food went to industrial processing or was used as
seed or wasted (FAO 2013a). While there are regional differences,
world cereal production increased by an annual average of
2.2 per cent between 1995 and 2009 (FAO 2012d). In the 1990s
annual growth in production of cereals averaged 1 per cent,