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Serious problems of land degradation, falling soil fertility, rapidly declining production levels and desertification are occurring in large parts of Latin America, Asia, Eurasia and Africa, a main cause being the plough-based or hoe-based agricultural practices. These inappropriate land management practices cause the soil to become more dense and compacted, the organic matter content to be reduced and water runoff and soil erosion to increase. They also lead to the effects of droughts becoming more severe and the soils becoming less fertile and less responsive to fertiliser.

There is now a wealth of evidence from examples throughout the world of these sustainable production systems and their dramatic effects that can be achieved when the basic principles of good farming practice are applied. The terminology being adopted for such systems by FAO and other organisations is much less thanConservation Agriculturemuch greater than (CA) and this implies conformity with all three of the following general principles:

no mechanical soil disturbance and direct seeding or planting

permanent soil cover, making particular use of crop residues and cover crops

judicious choice of crop rotations

Particularly renowned practices of conservation agriculture have been applied on a large scale on both large and small farms in Brazil and Paraguay. Other examples bear out the contention that minimal disturbance of the root zone, once this has developed, substantially contributes towards raising mean yields.

Globally, CA is now being practised on about 60 million ha, mostly in the Americas. Its use is growing exponentially on small and large farms in South America, encouraged by economic and environmental pressures. Over the last decade, FAO has been implementing field projects that place greater emphasis on helping farmers to improve their care of the land through practices of CA rather than through efforts solely to combat erosion. Its CA work initially concentrated in Latin America but FAO is now also focusing on Africa, Asia and Eurasia.

FAO has now established an interdisciplinary Conservation Agriculture Working Group (CAWG) and has made a wealth of information available through its specialist conservation agriculture web-site. It is actively supporting several CA networks such as RELACO, ACT, SACAN and ECAN.