Published June 1995
by Science Publishers .
Written in English
|The Physical Object|
|Number of Pages||462|
performance of agriculture on which their livelihood depends. Opportunities exist to improve the fortunes of farming households in the drylands. Improved farming technologies that can increase and stabilize the production of millet, sorghum, maize, and other leading staples are available. Irrigation is technically and economically feasible in. Future production growth in drylands agriculture is expected to come mainly from raising yields and increasing the number of crop rotations on land that is already being cultivated (intensifi cation), rather than from bringing new land into cultivation (extensifi cation). Agriculture in the drylands of India, which constitute 70% of arable lands, is discussed. They contribute up to 45% of foodgrains and 75% of the legumes and oilseeds produced in the country. These are both ecologically and economically disadvantaged areas but increased production could result from the introduction of high-yielding varieties coupled with the use of external inputs like Author: J. Venkateswarlu. production of crops impossible. The third situation is where water is brought in by wells, canals, or other means so that normal agriculture can exist, in spite of the aridity of the climate. This primer concerns the first two situations, but not the third. There are techniques suitable for all arid regions. PRINCIPAL ARID REGIONS OF THE WORLD.
Trees and shrubs offer enhanced sources of the organic matter needed to improve the structure and raise the fertility of soils used for agriculture. Many parts of trees provide different medicinal products for people. And fruits and vegetable foliage harvested from trees are important seasonal food sources for people living in drylands, and for. performance of agriculture on which their livelihood depends. Opportunities exist to improve the fortunes of farming households in the drylands. Improved farming technologies that can increase and stabilize the production of millet, sorghum, maize, and other leading staples are available. not have potential for agricultural production, except where irrigation water is available. While about 40 percent of the world’s total land area is considered to be drylands (according to the UNCCD classification system), the extent of drylands in various regions ranges from about 20 percent to 90 (Table 1 and Figure 1). Dryland agriculture refers to cultivation of crops entirely under natural rainfall without irrigation. It is a form of subsistence farming in the regions where deficit of the soil moisture retards the growth of water consuming crops like rice (Oryza sativa), sugarcane etc. Dryland areas are characterized by low and erratic rainfall and no assured irrigation facilities.
The key here is to avoid tree-crop competition, and hence trees must acquire resources that the crop would not otherwise get. Research has been active in this area during the last years, especially in African drylands, as a mean to increase crop production but also to combat desertification and increase soil C accumulation (Jama and Zeila, In this book leading scientists in the field describe the basic principles of dryland agriculture, and synthesize recent experiences and innovations in dryland agriculture research and development. It is a ready reference on the subject and reinforces the understanding for its utilization to develop environmentally sustainable and profitable. Furthermore, unlike in other regions, production of low-value cereals under irrigation is generally not economic in Sub-Saharan Africa unless the cereals can be grown in rotation with one or more high-value cash crops. The long-run strategy for drylands agriculture, therefore, must be to promote production of staples in rainfed systems and. Much of Australia’s agricultural income comes from the production of food and fibre on dryland farms (Squires, ). In Australia, dryland-farming systems combine crops, pastures and fallow periods for the purpose of making efficient use of the limited water. Moisture is usually the deciding factor in the success of cereal cropping.