Cacti: efficient tool for rangeland rehabilitation, drought mitigation and to combat desertification

Marginal lands often represent fragile ecosystems. Ploughing and indiscriminate vegetation removal can result in large-scale degradation and destruction of vegetation cover. To reverse the desertification trend and to restore vegetation cover in such areas, appropriate integrated programs are needed for rangeland monitoring, livestock control, and conservation of natural resources. The identification of plant species able to grow and produce in arid areas has been a permanent concern in most WANA countries. The characteristics of cacti fit most of the requirements of a drought-resistant fodder crop. Indeed, they possess a specialized photosynthetic mechanism, which leads to a more efficient production of dry matter per unit water consumed than that of grasses or legumes. Spineless cactus (O. ficus-indica), which is drought and erosion tolerant, is being advantageously and widely established in Tunisia and Algeria to slow and direct sand movement, to enhance the restoration of the vegetation cover, and to avoid the destruction by water of the land terraces built to reduce runoff. Large scale plantation of spineless cactus in Central and Southern Tunisia proved that this plant species play a key role in natural resources conservation and prevent long term degradation of ecologically weak environments. These plantations provide a valuable fodder used extensively to cover feed gaps especially during severe droughts. Cacti cladodes are unbalanced feed nutrientwise but a cost-effective source of energy and water. In arid and semi-arid regions, cereal crop residues and natural pastures generally do not meet the nutrient requirement of livestock. Cladodes can provide cost-effective supplement, such as for raising sheep and goat on rangelands. National strategies in several countries of WANA region started since several decades to overcome feed gaps and to restore degraded rangelands. These strategies focused mainly on large-scale plantations of fast growing species, such acacias and saltbushes. Pertinent experiments showed that sustainable feeding systems based on these feed sources associated with cactus are beneficial to these areas. Supplying livestock with water during the summer and drought periods is crucial in arid zones. Water scarcity depresses feed intake, digestion, and therefore animal performance. Therefore, the high water content of cladodes is beneficial in dry areas.