TheImprovement ofTropical and Subtropical Rangelands

200 IMPROVJ:AaNT 0' TROPIOAL AND SUBTROPIOAL RANGBLANDS
CcmIenatlcm aDd llehabWtatlcm
Anti-erosion revegetation projecta have been 8ucceafully carried
out in various countries under extremely arid conditions. For
instance, saksaulB (Hdoz,lora perftc.m, H. tlmmodendron, and Cdligon.m
spp.) have been UIed in the Near East.
Sand dunes can be stabilized by planting short shrube, such as
E.pAorbitl spp., perpendicular to the direction of the wind. Commonly
called palisades, this method requires a great deal of labor
since the planta must be closely spaced-from 10 cm intervals at the
base of the dunes to as close as 2 cm intervals near the tops of dunes.
Lateral rows also need to be created 110 that the effects oflateral sand
tran8port will be diminished. This may result in a grid or checkerboard
pattern. However, there must be enough space between shrubs
so that small quantities of sand can pass through. Otherwise, the
formation of dunes superimposed over the old dunes could result.
Local demonstration areas might be required to determine palisade
orientation, spacing, and height.
Whatever the species chosen, a program of protection and managed
use must be established and maintained to ensure the longevity
of the effort. Regardless of the method used, the m~or
obetacle is always the provision of appropriate management strategies
and an alternative livelihood for the populations concerned
until the revegetation projects become self-supporting. Ways and
means to accomplish thi8 should be 8pelled out in the feasibility
studies.
Other UHI
Revegetation projects may consider adjacent plantations that
can sustain multiple uses for one or more of the reasons previously
mentioned, such as using cacti (Opuntitl spp.) for ita fruits, fleshy
pads, and joints in northern Africa; mulberry (Moru dbtl) for fruita
and wine making, feed for livestock and wildlife, and silkworm forage;
cashews (Aratlctlrdium occidenttlle, European filberts (Coryla
tltlelltlntl) and pistachio-nuts (Puttlcitl tlertl) for fruits; E.cdpptu
spp. and Pro,opu spp. for honey. Other uses include chemicals,
gums, and tannins from species such u carob (Certltonitl ,iliqua)
and Actlcitl spp., and fibers from Agtltle spp.