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Agriculture and food production

Since 1972, the main driving force leading to pressure on land resources has been increasing food production. In 2002, food is needed for some 2 220 million more people than in 1972 (United Nations Population Division 2001). The trend during the decade 1985-95 showed population growth racing ahead of food production in many parts of the world, particularly Africa: in 64 of 105 developing countries studied in this period, food production lagged behind population growth (UNFPA 2001).

Agricultural land (defined as land under arable use plus permanent crops) has increased steadily in developing regions but not in developed ones (see graph). The decrease in developed regions seems to have been driven less by availability of land resources than by economic forces, including overproduction of major commodities and decreasing prices for farm produce.

Area under arable and permanent crops (million ha)
Area under irrigation (million ha)
Fertilizer consumption (kg per capita/year)

Graphs above show 30-year trends in three major agricultural variables: agricultural area, irrigated area and per capita fertilizer consumption. Fertilizer consumption has fallen in Europe and North America but continues to climb - albeit slowly - elsewhere

Source: compiled from FAOSTAT 2001 and United Nations Population Division 2001

Policy failure and poor agricultural practices contribute to increased land pressure. For example, the excessive use of fertilizers and other chemicals contributes to soil degradation and water pollution. Between 1972 and 1988, global fertilizer use grew at an annual average of 3.5 per cent or by more than 4 million tonnes a year (FAO 2001). Up to the 1980s, maintenance and improvement of fertility was thought of chiefly in terms of addition of mineral fertilizers, and agricultural subsidies increased the use of fertilizers further. Government policies supported farmers by subsidizing agricultural inputs such as irrigation, fertilizer and pesticides. A study by FAO of 38 developing countries showed that 26 of them subsidized fertilizer use (FAO/IFA 1999).

Pesticides continue to be used indiscriminately (sometimes illegally) in places, and disposed of casually. A survey published by FAO of countries in Africa and the Near East reported stocks of unwanted or banned pesticides amounting to more than 16 500 tonnes at some 1 000 sites in 49 countries (FAO 1995a).

Irrigation has also made, and continues to make, an important contribution to agricultural production but the potential for future growth has changed. The efficiency of many irrigation schemes is low and land degradation problems are widespread. Poorly designed and implemented irrigation schemes can cause waterlogging, salinization and alkalization of soils. Some 25-30 million ha of the world's 255 million ha of irrigated land were severely degraded due to the accumulation of salts, according to 1995 FAO estimates. An additional 80 million ha were reported to be affected by salinization and waterlogging (FAO 1995b). In the 1980s it was estimated that about 10 million ha of irrigated land were being abandoned annually (WCED 1987) although the total irrigated area has continued to rise (see graph above).