Sustainable Management of Rangelands and Agricultural Systems of the Drylands: The ICARDA Experience in Combating Desertification

摘要

The drylands of West Asia and North Africa (WANA) are under severe risk of desertification. The main drivers of land degradation in WANA are the expansion of cropping systems into more marginal land, reduction of fallow periods, and increased grazing pressure. These forces have resulted in different forms of degradation, of which loss of vegetation cover and diversity, increased wind and water erosion, and salinization in irrigated land are the most important. In collaboration with national agricultural research programs and international partners, ICARDA has addressed desertification in WANA through management strategies that aim to develop location-specific technologies on the basis of principles of holism, integration, and participatory development. These management strategies recognize that water is the most constraining resource in the drylands. Water must be efficiently used in order to meet the productivity and sustainability requirements of the major production systems. Research progress in reversing desertification in the region is outlined for management strategies related to range rehabilitation using direct rainfall, improving rainfall-use efficiency at the low-rainfall cultivation frontier, water harvesting, and irrigated agriculture. It is concluded that desertification is a reversible process but that early action and prevention is far preferable to costly rehabilitation of degraded land. The research challenge of desertification requires an institutional and concerted response in the form of increased collaboration between international, regional, and national centers with a mission in sustainable dryland development.