Population Density and its Modified Concepts

1. “Population is the point of reference from which all other phenomena are observed and from
which they all, singly and collectively, derive significance and meaning. It is population which
furnishes the focus.”
Concept of population density is first time used in 1837 by Henry Drury Harness in a series of
maps. He describes this concept as!
“Relation between numbers of people to the space occupied by them.”
We can define population density with respect to two approaches.
1. Aggregative approach or ranking method (this approach covers the whole population of
an area for study).
2. Distributive approach or percentage method (atomization or decompose the whole figure
to focus on single thing that is atomize an area into universe and sub-universe).
Density of population can also be defines as number of people per unit area. This can be
expressed with a simple formula given below.
When population (P) increase, density (D) of population tends to be increase providing the area
(A) remains constant. In agricultural countries we take density of population as number of people
per hectare to per acre of land known as agricultural density. Population is constantly changing
in 190 Less Develop Countries (LDCs). Only in 14 Most Developed Countries (MDCs),
population appears to be same but not constant.
Population distribution is a phenomenon. Distribution of population reveals the interplay of a
vast multitude of physical and man-made phenomena. Distribution of population acts as a
master-threat keep-able of weaving into a coherent pattern, the otherwise disparate strand of
phenomena over the surface of the earth.

2. Merits of population density
1 Population density has been developed as a means, partly of accessing over
population and under population of an area, by comparing its existing and potential
densities.
2 Population density is a useful abstraction, assisting in the analysis of the diversity of
man’s distribution in the space.
3 Crude density of population is the man/land ratio, have more significance for the
spatial comparison and differentiation of much smaller units.
4 Population density is useful for obtaining an index for the purposes of areal
comparison.
Modifications in the concept of population density
As people are congregation into more and smaller areas and leaving much of the earth surface
sparsely inhabited, it was inevitable that refinements of density concept should be made, by
modifications to the numerator, the denominator or both.
1 The Dasymetric technique devised by Wright is a modified concept of population
density. It is a method of drawing a map to show density of population, departing from large
administrative units with mean figures, and using reasonable guesses to produce realistic
categories, for which densities can be estimated. In Dasymetric technique, densities are
calculated only for inhabited areas, the remaining areas being left blank on population maps. In
Dasymetric technique, densities are also calculated for cultivable areas, and are known in France
as physiological densities. They are preferable for the crude densities for a country like Egypt,
where 96% of populations inhabit about 4% of the total area.
Objection
Physiological densities must be used judiciously, as land which is not cultivable is not
necessarily unproductive. Moreover, in some countries statistics of cultivable land are not
available; in others cultivable and cultivated land are not distinguished.

3. 2 Agricultural density is a modified concept of population density. In this, densities are
calculated for agricultural population. In Britain, where less than 5% of the active population are
employed in agriculture, the agriculture density may be of greater interests than densities of the
total population per unit of cultivable or cultivated land.
Objection
It is not easy to define agricultural population. Do we include only active males employed in
agriculture, or should we also evaluate the work of women, children and old people, all of whom
may play a very useful part in some countries?
3 Another modified concept of population density, introduced by the French geographer
Vincent suggested in 1946, called comparative density. It is a type of physiological density,
where the total population is related to land area, weighted according to its productivity. This
method has been carried a stage further by employing a standard land use unit, termed, “a hectare
of arable equivalent”. All arable land is assumed to be uniform value; orchards and gardens are
three times as valuable as arable land; meadow land has only two-fifth of the value and pastures
only one-fifth.
Objection
It is doubtful whether calculations of this sort throw more light on the problem of comparison of
population densities, as the value of agricultural land varies enormously.
4 In the perspective of environmental conservation, Allan has proposed a measure of
Critical Density of Population (CDP) which he defines as “the human carrying capacity of an
area in relation to a given land use systems, expressed in terms of population per square mile; it
is the maximum population density which a system is capable of supporting permanently in that
environment without danger to the land”. Three sets of information are used to calculate in CDP:
(A) the percentage of land cultivable by traditional methods, (B) The land use factor or the
relationship between duration of cultivation and fallow, (C) cultivation factor or acreage planted
per capita each year.

4. Objection
CDP is calculated as 100B . Naturally, these variables are not easy to define accurately, but
the CDP is a useful index in the study of subsistence economies.
5 The notion of economic density is another modified concept of population density. It
was proposed in 1934 by the French demographer Simon as a formula. Where is the
index of population size and is the general index of production for the same year. Simon
believed that he had discovered an index capable of determining the optimum density population
in relation to a base period. As other denominators in his formula, Simon also proposed (A) the
general index of consumption, (B) the general index of all economic activities, (C) average
income per person, (D) standard of living and (E) available diets.
Objection
George has insisted that such measures of economic wealth are inadequate unless examined in
the light of the different economic systems and of social evaluation. Furthermore, the calculation
of these denominators is vitiated by changing international conditions.
6 The concept of urban population density may use a variety of denominators including
(A) total urban area, (B) built-up area, (C) net area of occupied dwelling lots and (D) gross area
of occupied dwelling lots.
Objection
These densities throw little light on the congestion within towns, where vertical expansion partly
invalidates man/land ratios and gives no information about concentration of people within
buildings, houses and rooms.
7 Another modified concept of population density is “room densities”. It includes average
number of persons per rooms and it is a useful index of density of occupation as well as housing
conditions.

5. Objection
This concept ignores the size of the room, which is very important factor in accessing room
densities. Persons per room data are normally limited to private households, the size and the
composition of which are not taken into account by room densities. Census reports usually
provide data of the number and the percentage of private households living at different room
densities. In this, only habitable rooms are counted including living rooms, bed room, kitchens
but excluding sculleries, bathrooms, etc.
8 Nutritional density is another modified concept of population density. It is the measure
of how much nutrition can be produced from land. It is a ratio between the total population and
the amount of land under cultivation in a given area. If cropped area is 1 acre then u can get three
times higher yield from the same farmland. The World Health Organization reviews scientific
and operational issues related to human nutrition, specifically when developing world
populations are impacted.
9 Settlement density is a modified concept of population density. It is a measure
represents the amount of area in a country for each city with 100,000 people or more. In
the United Kingdom, there are about 13,000 square miles for each city.
Advantage of modified concept
Thus the concept of population density has been extended beyond the scope of geography. Every
modified concept of population density has its own merits and demerits. We should take as much
benefits as we can from them, and try to avoid their demerits.