Agricultural Pollution

Sustainable agriculture is one of the greatest challenges. Sustainability implies that agriculture not only secure a sustained food supply, but that its environmental, socio-economic and human health impacts are recognized and accounted for within national development plans. Sustainable development is the management and conservation of the natural resource base and the orientation of technological and institutional change in such a manner as to ensure the attainment and continued satisfaction of human needs for the present and future generations. Such Sustainable development (in the agriculture, forestry and fisheries sectors) conserves land, water, plant and animal genetic resources, is environmentally non-degrading, technically appropriate, economically viable and socially acceptable (FAO).

It is well known that agriculture is the single largest user of freshwater resources, using a global average of 70% of all surface water supplies. Except for water lost through evapo-transpiration, agricultural water is recycled back to surface water and/or groundwater. However, agriculture is both cause and victim of water pollution. It is a cause through its discharge of pollutants and sediment to surface and/or groundwater, through net loss of soil by poor agricultural practices, and through salinization and water logging of irrigated land. It is a victim through use of wastewater and polluted surface and groundwater which contaminate crops and transmit disease to consumers and farm workers. Agriculture exists within a symbiosis of land and water and, as FAO (1990a) makes quite clear, "... appropriate steps must be taken to ensure that agricultural activities do not adversely affect water quality so that subsequent uses of water for different purposes are not impaired."

Sagardoy (FAO, 1993a) summarized the action items for agriculture in the field of water quality as:

Establishment and operation of cost-effective water quality monitoring systems for agricultural water uses.

prevention of adverse effects of agricultural activities on water quality for other social and economic activities and on wetlands, inter alia through optimal use of on-farm inputs and the minimization of the use of external inputs in agricultural activities.

Establishment of biological, physical and chemical water quality criteria for agricultural water users and for marine and riverine ecosystems.

Prevention of soil runoff and sedimentation.

Proper disposal of sewage from human settlements and of manure produced by intensive livestock breeding.

Minimization of adverse effects from agricultural chemicals by use of integrated pest management.

Education of communities about the pollution impacts of the use of fertilizers and chemicals on water quality and food safety.

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