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“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.

Population Density and its Modified Concepts

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Page 1: Population Density and its Modified Concepts

“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.

Page 2: Population Density and its Modified Concepts

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.

Page 3: Population Density and its Modified Concepts

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.

Page 4: Population Density and its Modified Concepts

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.

Page 5: Population Density and its Modified Concepts

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.