TheImprovement ofTropical and Subtropical Rangelands

THE ECONOMIC CONTEXT 55
proved extremely difficult. In resource-poor environments such as
arid rangelands, the assessment ofvalues iI highly time- and locationspecific.
Not only do values vary over time and space, but also among
individuals, households, tribes, and generations. The cost (negative
value) of soil degradation will be felt more by future generations than
by present ones (who might be causing the degradation).
Fourth, and related to the third point, is the difficulty in U8e88ing
the social costs and benefits (as opposed to the private values).
Communal grazing is believed to occur with virtually no cost to the
herders, but with possible social costs (in the case of overgrazing)
to the society as a whole. In the same vein, the long-term costs
are not necessarily the same as the short-term costs. This problem
is aggravated by the fact that the life span of range management
projects is generally limited to 10 years or lel!8, even in projects that
attempt to deal with long-term problems, such as desertification and
erosion. Another example of social costs is the negative effect that
a project might have on resources or persons outside the project
area. For example, the development of a pocket of highly productive
rangeland for crop cultivation might have a negative impact on the
usefulness of the surrounding low-quality rangeland because during
a drought period cattle would not have access to a highly productive
forage source (Sanford, 1983). Other social costs or benefits include
the impact of interventions on employment and equity.
Finally, we cannot overlook the fact that many projects have
failed for reasons other than inadequate economic analysis. For
example, biological scientists and technicians have often provided
projects with short-term, single-commodity technical input-output
relationships that have contributed to illusionary expectations of
possible changes in management behavior.
For some time, pastoralists have therefore been labeled "irrational,"
but this allegation has been refuted by a growing number of
case studies. Cattle portfolio models developed in industrial countries
have found useful applications in pastoral situations (Jarvis,
1980j Ariza-Nino and Shapiro, 1984), and elements of Mrican and
Asian range management systems are finding application in industrialized
countries (National Research Council, 1984).
RANGE SYSTEMS
A range system is the arrangement of soils, water, crops, livestock,
labor, and other resources that the manager works according