TheImprovement ofTropical and Subtropical Rangelands

THE EOONOMIO OONTEXT 59
Climate and culture play dominant roles in transhumant systems,
comparable to those of the nomadic systems. Because of the
crop activities, some of the land is privately owned (or rented). Some
of the large ruminants are used for draft purposes, but the application
of manure provides a linkage between the livestock and the crop
component of this farming system.
The common feature of both the nomadic and the transhumant
farming systems is the mobility of the households. This strategy to
meet the variability in the physical environment is associated with
unstable control ofresources, notably land and water, and difficulties
of planning herd size and herd movements.
Ownenhtp
The three types of land ownership are communal, modified communal,
and exclusive (Lawry et al., 1984). Exclusive land tenure
(private ownership or lease) has been seen by some as a solution
to overgrazing. Overgrazing in turn is believed to find its economic
rationale in the "tragedy of the commons": the individual herdsman
has no economic incentive to reduce the number of animals as long
as there is free access to communal land and water. Although assignment
of grazing rights is advocated as a solution (Doran et al., 1974;
Jarvis, 1980), experience has not yet shown that tenure reform is an
effective policy instrument (Lawry et al., 1984, p. 247). One of the
problems ia that stock limitations specified in leases are almost never
enforced. There is also growing evidence that pastoralists are very
aware of the need for rangeland conservation and will act accordingly
(National Research Council, 1986).
Narrowly related to the issue of land ownership is that of access
to water. Because moisture is the overriding limiting factor in pastoral
management, access to water is crucial. In many cases, control
of water supply implies de facto control of land use. Water sources
can be clusified according to ownership in a similar way. Other classifications
are made according to the technical operations (including
boreholes, dams, wells) or size.
THE BASIS or RANGE ECONOMICS
Economics may be defined as the science dealing with the allocation
of scarce resources among various competing uses, with the
objective of maximizing utility or maximizing satisfaction of human
wants. For range projects, scarce resources include: