TheImprovement ofTropical and Subtropical Rangelands

278 IMPROVEMENT OF TROPIOAL AND 8UBTROPIOAL RANGELANDS
(migration route), use is shared with agriculturalists and with other
migratory tribes. What ownership really means in the nomadic context
is the right to exclusive usufruct of the particular section of the
il-raJa that the tribe happens to occupy at any particular time. The
Baseeri claim the right to p.. between summer and winter pastures
in their strip of land, to draw water from natural sources, and to
pasture their flocks on uncultivated land. The territory contained
within the il-f'f&1a and the precise boundaries of the il-f'f&1a are quite
vague. This is not important, however, since tribes move along their
il-raJa in a resuIar schedule and follow a particulat path determined
by the availability of gr.., water, and mountain passes. The number
of tribesmen using or paseing through an area is adjusted to the
carrying capacity of that area.
Within the tribe, the chief uses his authority to assign a particular
sequence and division of land utilization among various sections
of the tribe. He also exerts his authority, backed up by the political
power of his entire tribe, to arrive at adjustments in the migration
pattern v."vis other tribes. Thus, the territory that the Basseri
occupy at one time during the year may be the ·property" of another
tribe later in the year. For example, the Kurdshuli tribe proceeds
northwards ahead of the Basseri, while Arab, Baseeri, and Qashqai
tribes all arrive at the Mary Dasht valley at about the same time. s
Since a particular tribe follows the progressive development of pasture
northwards, it is restrained by the pre88Ure ofmaturing pastures
ahead and withering pastures behind, as well as the pressure of other
tribes preceding, following, or paralleling its line of march. According
to Barth, ~he il-rGIa of a nomad tribe is thus a schedule of
traditional rights to utilise certain places at certain times. These
rights are also traditionally sub-divided and alloted within a tribe
among its various sections, so alternative routes in the il-f'f&1a are held
by different sections.» T The result is a flexible system that can be
adjusted to changes in the relative strength and importance of tribes
and sections v."vis each other.
The Migration Route: UtlllJatlon of Succe..lve PUturll
In their pastoral exploitation of the natural environment, the
Basseri are entirely dependent on the utilization ofsuccessively available
pastures. Different sections of the tribal il-rGIa are grazed at
different times during the year with the particular sequence being
dependent on the availability ofwater and of grass.I The sheep raised