TheImprovement ofTropical and Subtropical Rangelands

THE SOorAL OONTEXT FOR RANGELAND IMPROVEMENT 49
new technologies often requires changes in traditional institutions,
hence an unintended consequence may be a weakening of those institutions
that have in the past protected the environment. In this light,
publicly funded revegetation programs may be seen as attempts to
correct some of the excesses of rapid social change.
AB we can see, then, desertification and the destruction of plant
cover have been caused by a number of factors. It is important
to remember from these examples that environmental deterioration
has been accelerated because the mechanisms that formerly helped
people adapt tosemiarid and marginal environments have been weakened.
Diversification and mobility have been limited, and the feedback
from man's use of the environment has been distorted. Ifrevegetation
efforts are to be successful, they must create a sustainable
human ecology as well as stable, productive environmental systems.
Too often, projects have undermined themselves by ignoring people,
or by inadvertently accelerating the processes of declining diversity
and mobility in production systems.
Successful revegetation requires changes in land use patterns so
that the reestablishment of vegetation is encouraged. In the past,
attempts have been made to control access to revegetated areas
by changing land tenure arrangements. Nomads have been settled,
private and group ranches have been created, and forest reserves have
been legislated, all in attempts to control access to project lands by
reducing animal movement and by restricting people to particular
parcels of land. AB previously mentioned, the reduction of mobility
may threaten the viability of traditional subsistence systems. Iftheir
livelihood is threatened, people may resist overtly or may passively
resist by bribing forest guards or by grazing or cutting revegetated
areas when they are not being properly guarded. Conflict between
traditional users at the very least raises the cost of revegetation
substantially, and may in many instances negate project efforts.
In some cases, the failure to understand the importance of mobility
can mean disaster even when project goals are attained. Boreholes
are examples ofefforts to increase available pastures that, in fact, led
to local desertification and to heavy livestock losses during droughts
(figure 2-4). At other times, the success of programs in one area may
lead to larger levels of environmental deterioration outside a project
area. Herds that are required to leave the area of a range or reforestation
project must go somewhere, hence the revegetation projects
may accelerate the processes that they are intended to reverse. The