Page 35 - Life & Land Use on the Bahrain Islands (Curtis E Larsen)

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of artesian springs are located. A measured area for this favorable land as derived
from 1956 aerial photography is 85 km^, less than 14% the total available land.
When viewed in terms of population density as calculated from the 1971 census, the
average density is 408 people/km^, but this becomes 2941 people/km when only
the arable land is considered. The Manama-Muharraq urban center alone shows
27,060 people/km^ by comparison. Thus, even though land area is physically

limited, it is used in a still more restricted manner by the present population.
Traditional farming has relied upon the natural availability of artesian
water from the Eocene age aquifers to supply various gravity flow irrigation
systems. However, natural springs occur only in the northern portion of the island.
Modern well-drilling has provided farmers with methods for locating wells near
arable land, and gasoline-powered pumps have aided in the extraction of water, but
the best water is also restricted to the northern quarter of Bahrain.
Usable soils are important factors. For agricultural use in an arid region,
soils should not only provide necessary nutrients, but should also be able to offer
adequate drainage. Inadequate drainage properties can lead to an increase in soil
salinity, a potential check on plant viability. Bahrain’s best potential soils are
found along the coastal plain surrounding the flanks of the geologic dome. These
are derived from coastal deposits left by past incursions of higher sea level during
the Pleistocene, as well as from the weathering products of the local limestones
and dolomites transported by intermittent flow in the various wadis, Unlike
freshwater sources, the soils extend around the periphery of the main island. In the
central depression, physical and chemical weathering of surrounding rocks, as well
as redeposition by wadi flows have combined to provide still other potentially
arable soils. Yet, though this area of arable soils is great, it is unusable without
irrigation. Therefore, even the use of the existing soils is confined to the areas of
the greatest water.

Bahrain, like the Arabian Peninsula, is located within the Saharo-Arabian
arid zone that occupies North Africa, and parts of Iran, Pakistan, and India
(Rumney 1968). Temperatures in Bahrain average 26.4°C during the year with the
highest average monthly temperatures (32.3°, 33.9°, 34.1°C) during June, July, and