Description
The Green Revolution, based principally on a package of improved seeds, chemical inputs and
irrigation, and supported by measures to strengthen agricultural policies and institutions, resulted in
major increases in productivity and production of staple crops in a number of countries, especially in
Asia. Arguably, the intensification of food production under the Green Revolution also did much to
preserve fragile, marginal, and forest lands that would otherwise have been cultivated for food crops
more extensively (Stevenson et al, 2011). Real per capita incomes almost doubled in Asia between
1970 and 1995, and poverty declined from nearly three out of every five Asians in 1975 to less than
one in three by 1995. Much of this decline is attributable to agricultural growth – particularly in
smallholder farming systems, with accompanying declines in food prices and rising rural incomes. At
the same time, it has been associated with high levels of energy use; and in many areas over‐use of
agro‐chemicals and reliance on intensive mono‐cropping has resulted in environmental degradation,
including unsustainable use of water and high levels of fertilizer run‐off, pesticide impacts, loss of
agro‐biodiversity, soil contamination and land degradation. Thus agricultural intensification has been
at the same time both a saviour and a threat, illustrating the importance of mainstreaming
sustainability into a new intensification agenda.
Overall, over the past half‐century, intensive agriculture has increased global food production and
enabled higher average per capita food consumption in many parts of the world – even if in recent
years rates of productivity growth have declined. At the same time, in other parts of the world
agriculture has continued to perform below its potential due to low levels of use of external inputs.
This is true in many parts of Africa in particular where, with some important exceptions, agricultural
productivity has shown only little or no growth. Low rates of agricultural growth combined with high
rates of population growth mean that many African countries have gone from being net food
exporters to become net food importers.
Agriculture is, by its very nature, a major user of natural resources, although in different ways and to
different extents depending on farming system. Thus livestock is the world’s largest user of land
resources, using almost 80 per cent of all agricultural land; while globally, some 70 per cent of the
water used is consumed by the agriculture sector (Kabat, 2013). Of greater concern is the fact that
some agricultural systems are drivers of environmental degradation and loss of biodiversity (FAO,
2009; IAASTD, 2009, UNEP, 2010). Over 60 per cent of the world’s major ecosystem goods and
services are being degraded or used unsustainably (MEA, 2005), while the genetic diversity of crops,
breeds, trees and aquatic resources on which agriculture depends is at severe risk: this owing to
global environmental change as well as the loss of knowledge associated with agricultural practices
based on local varieties. Today, three crops only – wheat, maize and rice – supply more than half of
humanity’s calories. In addition, agriculture and land‐use change (mostly bringing forest land under
cultivation) is a major source of greenhouse gases, producing between a quarter and a third of all
emissions; and more than any other sector, agriculture is already adversely affected by
unpredictable and extreme effects of climate change. In the future, higher average temperatures are
expected to reduce yield levels, particularly in the developing world; while increasingly unreliable
weather conditions will likely undermine productivity growth everywhere.
At the same time, roughly one‐third of food produced – 1.3 billion tonnes per year – is lost or wasted
globally (FAO, 2011b). Food is lost or wasted throughout the supply chain, from initial agricultural
production down to final consumption. In medium‐ and high‐income countries there are high levels
of food waste at the consumption stage. In low‐income countries, by contrast, food is lost mostly on‐
farm – due to pests or lack of effective storage – or in transportation and processing. While
increasing food production is vital to meet the future increase in final demand, food availability can
also be increased and the environmental costs of agriculture production reduced by reducing the
amounts of food lost and wasted.
The challenges facing agriculture – crop, livestock, fisheries and forestry – over the coming decades
are complex. To meet the growing demand for food, feed, fuel and fibre, agricultural systems need
to become more productive and less wasteful. They need to provide decent incomes for farmers,
including the landless and waged agricultural workers, and create employment in the rural areas
that respects labour standards. They must be more efficient and more sustainable, in terms of their
use of, and effects on, the natural resource base. They need to be more resilient to shocks and
changes, better able to withstand increased climatic shocks and rising temperatures. They have to
reduce their levels of GHG emissions. They also have to provide other important ecosystem services,
such as water provision, pollination, flood and disease control and maintenance of soil fertility. They
need to reduce their dependence on fossil fuels: sustainable agriculture necessarily relies on clean,
green, renewable energy and increased energy efficiency. And finally, less produce must be wasted
or lost post‐harvest. All of these challenges require that food and agricultural systems are made
more sustainable, not only from an economic perspective but also from environmental, social and
institutional perspectives and at various scales, from the local to the global level.
This requires a consistent focus on production systems that draw more effectively on production
ecology principles to improve their productivity and efficiency while reducing their negative
environmental and social impacts. Sustainable agricultural systems are likely to be associated with a
more targeted use of external inputs, a more integrated approach to managing natural resources,
and more analysis at the landscape/eco‐system level together with better management of
ecosystem services. They are based on ecosystem approaches that conserve, manage and enhance
natural resources and take advantage of the natural biological inputs and processes such as soil
organic matter, natural predators of pests and pollination.



