WWF-UK Research centre: Facts and key issues

Boy with grain, WWF-Canon/John E. NEWBY/S. MBANEFO OBIAGO

UN predictions of the global population increase between now and 2025 will require a 40-45 per cent expansion of food production.

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Agriculture facts and key issues

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The Global Picture
Key Impacts on the Environment
Key Recommendations
Footnotes

Agriculture has widespread and significant impacts on the environment in four principal areas: water, soil and air pollution; water use; land and habitat conversion; and soil degradation. In order to address these impacts, socio-economic interventions are required as follows:

Improving sourcing strategies of major agri-businesses: Major global food and fibre businesses should seriously address, and achieve measurable improvements in, the social and ecological impacts of their sourcing strategies.

Encouraging equitable international trade: Production subsidies and price support should be greatly reduced, with remaining interventions targeted at social and environmental goals. Developed world export subsidies and export credit should be removed and import barriers significantly reduced.

Reducing the over-use of inputs: Better management practices, and systems to enforce them, should be instated across the world. Water resources management at the catchment scale, tradable water rights and equitable decision-making over water allocation, should be established. Governments and the financial sector should not support the over-development of irrigation.

Creating markets for environmental services: Schemes should be established, and existing schemes extended, that provide farmers with financial incentives to produce in environmentally sympathetic ways.

The Global Picture

24 per cent more food was produced per person on the planet in 1997 than in 1961.(1)
30 per cent of world agricultural land is devoted to crops and 70 per cent to pasture.(2)
By 2000, 75 per cent of the world's food came from seven crops - wheat, rice, corn potatoes, barley, cassava and sorghum. Some 60 per cent of the world's food calories came from the first three alone.
By 2030, developing countries will be responsible for 72 per cent of world crop production.(3)
80 per cent of growth in crop production in the next 30 years will be due to increased intensity (increasing multiple cropping and shorter fallow periods) and yields, while only 20 per cent will be due to expansion of arable land.(4)
The human population now uses between 20 and 40 per cent of the total world primary production, with levels in excess of 40 per cent in many industrialised countries and as high as 90 per cent in intensively cropped regions.(5)

Key Impacts on the Environment

Negative environmental impacts from agriculture result from converting natural ecosystems to agricultural production and from intensifying agricultural systems. The impacts of agriculture on the environment fall into four broad areas:

Water, soil and air pollution

Agriculture contributes about 30 per cent of total global anthropogenic emissions of greenhouse gases. Tropical forest clearance and land use changes were major factors in the past, but these are not projected to increase significantly in the next 30 years. The contributions of methane and nitrous oxide from livestock and biomass burning may increase by up to 60 per cent over the next 30 years.(6)
Agriculture is responsible for the pollution of waterways with phosphates, nitrates, suspended solids and pesticides. In the UK, phosphate contamination of rivers from agricultural sources doubled between 1931 and 1991.(7) In some areas of Europe, agriculture is estimated to be responsible for up to 80 per cent of the nitrogen loading and 20 to 40 per cent of the phosphorus loading of surface water.(8)

Water use

Agriculture is responsible for 70 per cent of global water withdrawals.
In 1995, 41 per cent of the world's population - 2.3 billion people - lived in water-stressed river basins. Under current consumption patterns this number will rise to 3.5 billion (48 per cent of the world's population) by 2025. Of these, 2.4 billion will live in highly stressed water basins.(9)
Total world water withdrawals rose more than 50 per cent between 1970 and 2000, from 2,500 km3 pa to over 3,900 km3. Total water withdrawals are projected to grow by more than 10 per cent every 10 years, and by 2025 will reach approximately 5,100 km3 pa. (10)
To provide 2,700 calories a day requires 4300 litres (equivalent to more than seven bathtubs) of agricultural water use. The variation is considerable, however: to provide 500 calories in the form of maize requires 130 litres of water, while the same number of calories produced as beef requires 4,900 litres.(11) Between 1997/99 and 2030, annual meat consumption in developing countries is projected to increase from 25.5 to 37 kg per person, compared with an increase from 88 to 100 kg in industrial countries.(12)
Compared with conventional or furrow irrigation, drip methods often reduce the volume of water applied to fields by 30-70 per cent and increase crop yields by 20-90 per cent. In combination this can mean a doubling or tripling of water productivity. Use of drip and micro-irrigation ranges from 90 per cent share of total irrigated area in Cyprus, through 17 per cent in Spain and South Africa to 4 per cent in the US and <1 per cent in China and India.(13)

Land and habitat conversion

Agricultural land use rose from 34.9 per cent to 37.7 per cent of the total world land area in the 30 years before 1997.(14) This is equivalent to the conversion of an area the size of Greece or Nicaragua each year.
Thanks to research, yield gains from agriculture over the last 30 years have resulted in increased production equivalent to the conversion of 230-340 million hectares of forest and grassland to cropland.(15)
While total land conversion rates are likely to decrease over the next 30 years, increased frequency of conversion of wetlands and high gradient land will have a disproportionately large environmental impact.(16)
The impact of land conversion has been more significant in some areas: while 40 million hectares of land have been withdrawn from agricultural use in the US, western Europe and Oceania over the last 40 years, 300 million hectares (17) of the remaining 1,700 million hectares (18) of tropical forest were lost in the final two decades of the 20th century, primarily to agricultural conversion.
Agricultural land conversion has not only taken place through expansion into new areas, but also through the conversion to more intensive use of existing farmland. Changed farm practices in the UK are believed to be responsible for a decline in more than 40 per cent of farmland bird populations since 1970.

Soil Degradation

1,964 million hectares of land have been affected by land degradation, with 46 per cent of agricultural land moderately degraded and 16 per cent strongly degraded. Regionally, strong degradation varies from 41 per cent of agricultural land in Central America to only 1 per cent in the US.(19)
In south Asia, 25 per cent land is suffering from water erosion, 20 per cent wind erosion, 13 per cent soil fertility decline, 9 per cent salinisation, and 2 per cent water-logging. (20) Water-logging and salinisation are localised acute phenomena - for example, in the Western Punjab and Indus valleys.

Key Recommendations

The negative environmental impacts of agriculture need to be addressed through social and economic interventions in how food and fibre is produced and sold.

Improving sourcing strategies of major agri-businesses
Agricultural markets are undergoing rapid vertical and horizontal integration, resulting in a concentration of power: a few hundred large companies are increasingly responsible for purchasing global agricultural commodities.

What should happen: Major global food and fibre businesses should seriously address, and achieve measurable improvements in, the social and ecological impacts of their sourcing strategies.

Encouraging equitable international trade
The international trade in agricultural products is inequitable and environmentally destructive. Production subsidies in developed countries, estimated at 40 per cent of farm income in the US and 23 per cent in the EU in 1998-2000(21), result in environmentally destructive over-production. Export subsidies and credit result in these products being sold in the developing world at artificially low prices. Combined with barriers to imports in key agricultural sectors, this undermines developing world agriculture and poverty alleviation.

What should happen: Production subsidies and price support should be greatly reduced, with remaining interventions targeted at social and environmental goals. Developed world export subsidies and export credit should be removed and import barriers significantly reduced.

Reducing the over-use of inputs
Many negative environmental impacts of agriculture result from the over-use of inputs such as pesticides and fertilisers. Over-use occurs for a range of reasons: farm management is easier than with more targeted inputs; risks of under-use can be avoided; inputs are often subsidised; and strong markets exist for the sale of inputs such as pesticides, while there are few markets for the knowledge that lies behind improved management. Particularly acute is the misuse of water: if the massive expansion of irrigated agriculture in the next 50 years is poorly managed, it will result in inequitable and inefficient allocation of water leading to environmental destruction and significant adverse social consequences.

What should happen: Better management practices, and systems to enforce them, should be instated across the world. In the water sector, water resources management at the catchment scale, tradable water rights and equitable decision-making over water allocation should be established. Governments and the finanical sector should not support the over-development of irrigation.

Creating markets for environmental services
Because there are no markets for the environmental benefits produced by agricultural systems - for example, biodiversity support or catchment management - farmers have no incentives to operate in ways that support environmental systems.

What should happen: Schemes should be established, and existing schemes extended, that provide farmers with financial incentives to produce in environmentally sympathetic ways.

Footnotes