Page 221 - Life & Land Use on the Bahrain Islands (Curtis E Larsen)

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Of the five land areas chosen, four displayed the anticipated exponential growth
relationship. Tie Barbar II data varied beyond three standard deviations from a
least-squares regression line and was deleted from the final calculation as an
anomalous figure. A regression line calculated for the remaining four points in
Figure 38 yielded a close correlation (r = 0.988). The resulting curve is expressed
by the equation log y = 0.0002x + 2.315. This indicates a long term growth in
cultivated land area at a rate of 0.05 percent per annum. Parallel regression lines
were drawn for both maximum and minimum populations. The modern population
curve is also shown for comparison.
Tie range of population sizes for the Barbar n phase were greater than
the range described by the other data. In both cases, the Barbar population
estimate was comparable to the medieval estimate. This anomaly resulted from
use of the same total land-use area for both periods. Tie upper population limit
shown is greater than the estimated population for 1890 and must be considered to
be inapplicable for Bahrain. Similarly, the average population size of 17,207
calculated for the Barbar n phase and based upon the contemporary tombs yielded
2
a population density of ca. 113 persons/km .
Close agreement between estimated and actual data suggests valid
population relationships. It should be emphasized that these data are not critical
population densities, nor do they represent the carrying capacity of the available
land. Tiese are better defined by Allan (1973).

In the context of traditional subsistence agriculture,
the CPD (critical population density) is the maximum
population density an environment can support permanently,
under a given system of land use, without damage to the
land. Tie term "carrying capacity" has a similar
connotation. [Allan 1973:217]

Tie concept of carrying capacity has recently come into question as a measurable
quantity by Street (1969). Alland (1975) claims it to be an interesting theoretical
tool, but practically impossible to quantify. In any event, suggestions of differing
crop preferences through time on Bahrain eliminate assumptions for a constant
capacity. Historical records as early as the third millennium B.C. report that