Agriculture Reference
In-Depth Information
of Bīr ¡ and and in the frontier zone with
modern Af ānistān. South-west of the
central desert is the basin of the Zāyanda
Rūd, which supports Ifahān and to the
south of this, the basin of the Kur. The
discharge of most streams in the central
zone is small. Many of the larger streams,
gathering in high mountains, have steep
and irregular profiles. Leaving the moun-
tains, they dwindle quickly as a result
of evaporation, seepage and diversion
for irrigation, leaving dry channels, the
underflow of which now and then sup-
ports an exotic agricultural efflorescence.
From ancient times, the water of these
rivers and streams has been used for irri-
gation and has formed the basis on which
flourishing civilisations have been estab-
lished in pre-Islamic and Islamic times.
The history of the water use of the Kur in
the Marwda ª t plain illustrates the impor-
tance of the role played by irrigation in
the establishment of the early Persian
empires in that region and the changes in
the prosperity of the region and the den-
sity of settlement which took place over
the centuries as a result of fluctuations in
the upkeep of dams and irrigation chan-
nels. For the most part, the rivers flow-
ing into the southern end of the Caspian
Sea, apart from the Oxus appear to have
been less used for irrigation in early and
mediaeval times than the rivers in central,
southern and eastern Persia. amd Allāh
Mustawfī states that little of the water of
the ur ¡ ān River was used for irriga-
tion and most of it ran to waste. Similarly,
hardly any of the water of the Safīd Rūd
was used for irrigation, except for that lit-
tle which watered the lands lying immedi-
ately along its bed; most of it was wasted;
and the same, he alleges, was true of its
tributary, the · āhrūd, though this was
not so in the case of the rivers of the two
ārums, which also flowed into the Safīd
Rūd: in summer most of their waters were
used for irrigation and little flowed into
the Safīd Rūd.
The smaller basins of the arid centre
of Persia and the south-east, together with
the fringes of the kawīr , receive incoming
water mainly by piedmont seepage of
many small ephemeral streams. The tra-
ditional method of tapping this water is by
anāt , which, with its associated network
of canals, is characteristic of irrigation on
the Persian plateau; hence too the fre-
quent siting of settlements on gentle slopes
some distances from the foot of the hills
that feed the anāt s. From earliest times,
the material basis of the population on
the Persian plateau has been provided by
anāt water. The various systems of irri-
gation—by river, anāt , spring or storage
dam—are not mutually exclusive; many
districts use more than one.
The configuration of settlements has
been decided in many cases by the nature
of the water supply. Where water is scarce,
villages tend to be concentrated; else-
where they may be more scattered. They
frequently flank water-courses and cluster
about the outlet of anāt s or round springs.
The area immediately round a town or
village is usually intensively cultivated
with irrigation—even in the dry farming
regions there is often a small irrigated
area in or near a town or village. Beyond
the cultivated land there is sometimes a
periphery of marginal land which may be
cultivated in years when the water sup-
ply is extraordinarily plentiful. Similarly,
mountain villages in regions where the
rainfall is sufficient for cultivation usually
have an irrigated area, however small.
In mountain valleys, the villages tend to
be situated on rocky slopes rising above
the intensely cultivated valley floors or
to straggle along the mountain streams.
Mountain slopes are often skilfully ter-
raced, and much time and labour is
expended on the construction and repair
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