TheImprovement ofTropical and Subtropical Rangelands

THE ECONOMIC CONTEXT 57
• The cash income from livestock activities often occurs at irregular
intervals and on special occasions; it is easily ifnot intentionally
overlooked during household surveys (Sabrani and Knipscheer,
1982). Even if scientists have explicitly focused on the livestock
component of the range system, they have encountered a number of
additional problems. Table 3-1 compares livestock-oriented farming
systems research with crop-orientedfarming systems. Factors such as
genetic variability, differences in age and productivity, and problems
with farmer cooperation, measurement ofeffects ofinput and output,
and representativeness of prices have constrained the researcher in
conducting on-farm trials (Amir et al., 1985). Consequently, rangeland
research has proved to be time-consuming, logistically difficult,
and expensive.
Major :reatures of Nomadic Systeml
Nomadic systems are based on livestock, and the main source of
income is derived from meat and animal by-products. Typical for
nomadic systems is the annual migration of livestock and managers,
for example, from highlands in the summer to plains in the winter, as
in the arid and semiarid region of Asia. The inftuence of climate as
well as culture is large, as families or tribes or both travel together,
following the opportunities that the climate offers. In this kind of
culture, crop farming is held in low regard. The crop component
in nomadic production systems is virtually nonexistent. The linkages
between livestock and other household activities are found in
household processing (for example, wool and weaving) and fuel supply.
Land use is characterized by grazing and collection of fuelwood,
while the manure of the animals returns some of the nutrients to
the soil. Although nomads generally are believed to be unconcerned
with improvement of feed resources, it is also known that they are
aware of the importance of future pasture availability and, therefore,
are careful in their grazing practices (Camoens et al., 1985).
Major Peatures ofTrmalmmmt SyRema
The critical difference between nomads and transhumants is the
existence of a substantial crop-producing activity in the household
system. Transhumants migrate seasonally with their flocks but have
a permanent residence area. The crop enterprise is generally for
subsistence, while the livestock component is geared for the market.