农业技术

抽象的

Perspectives on the Potential of Silvopastoral Systems

C Devendra

The importance of animal agriculture on productivity enhancement, nutritional and food security for economic rural growth in Asia is discussed in the context of the biophysical environment, available natural resources, preponderance of small farm systems, and opportunities for increasing the potential contribution. Arable land is a critical limiting factor, and an alternative to consider are the rainfed areas. The rainfed humid/sub-humid areas found mainly in South East Asia (99 million ha), and arid/semi-arid tropical systems found in South Asia (116 million ha) are priority agro-ecological zones (AEZs). They have been widely referred to as the less favored areas (LFAs), and low or high potential. The LFAs are characterised by very variable biophysical elements, notably poor soil quality, rainfall, length of growing season and dry periods, extreme poverty, and very poor people who continuously face hunger and vulnerability. There also exist large populations of ruminant animals, notably goats and sheep. About 43-88% of the total human population depends on agriculture for their livelihoods, of which 12-93% live in rainfed areas and 26-84% on arable land. In India for example, the ecosystem occupies 68% of the total cultivated area and supports 40% of the human and 65% of the livestock populations. Revitalised development of the LFAs is justified by the demand for agricultural land to meet human needs e.g. housing, recreation and industrialization; use of arable land to expand crop production to ceiling levels; very high animal densities. Animals play a multifunctional role and more importantly they can serve as the entry point for the development of LFAs. Efficient production systems are important and silvopastoral systems are underestimated and also underutilized throughout the developing countries, and especially where tree plantations are abundant such as with oil palm in Indonesia, Malaysia and Colombia. Concreted development attention together with research and development is necessary to promote its many economic advantages e.g. total factor productivity per unit land or labour, and value addition. Additionally, the system also promotes stratification, which provides an important opportunity to intensify NRM The strategies for promoting productivity growth will require concerted R and D on improved use of LFAs, application of systems perspectives for technology delivery, increased investments, a policy framework and improved farmer-researcher-extension linkages. These challenges and their resolution in rainfed areas can forcefully impact on increased productivity, improved livelihoods and human welfare, and environmental sustainability in the future.