Population: This refers to the total number of people living in a respective region.
Pattern of population distribution: This refers to the way in which people are spread across the surface of the earth.
Migration : This refers to the movement of people from one region to another.
Birth rate: This refers to the number of live births per 1000 people.
Death rate: This refers to the number of deaths per 1000 people.
Natural death rate: This is the difference between the birth rate and death rate.
Life expectancy: This refers to the expected number of years which an average individual can expect to live. It is calculated on the basis of the existing data for a particular region.
Emigration : Movement of people to other countries.
Natural growth rate :The difference between the birth rate and the death rate.
Sex ratio : It is the proportion of males and females in a given population. It is expressed in terms of females per 1000 males.
Life expectancy : It is the number of years that an average person is expected to live.
Distribution of Population
The way in which the people are spread across the world’s surface is called the pattern of population distribution. Population is very unevenly distributed as 90% of the world’s population lives on just 10% of the land surface. Many more people live in the northern hemisphere than in the southern hemisphere, and very few people live in high altitude areas, tropical deserts, high mountains and areas of equatorial forests. The most crowded areas are south and southeast Asia, Europe and north eastern North America. Almost 3/4th of the world’s population lives in the Asian and African continent. Thus, we see that the population distribution is highly uneven.
The geographical factors affecting the distribution of population are:
(i) Topography: People generally prefer living on plains rather than on mountains or plateaus, as these areas are suitable for farming and other similar activities.
(ii) Soil: People prefer to live in areas with fertile soil as it supports agriculture.
(iii) Climate: People avoid extreme climates.
(iv) Water: People prefer living in the areas where fresh water is easily available.
(v) Minerals : People are attracted towards the areas rich in mineral deposits.
Basically, the population can be divided into three age groups :
(i) 0-14 years
(ii) 15-64 years
(iii) 65 years and above
In these age groups, the 15-64 years age group is considered as working age group and the other two age groups, i.e. 0-14 years and 65+ years are known as dependent age groups or non-working age group.
So, about 61% of the Indian population lies among the working class, but about 39% of the population lies in the dependent age groups and this is a very high percentage. If we compare the age composition of Indian population with other countries, then the scenario will become clearer at global level.
At global level, the percentage of working class in India is higher than the low income countries, but it is less than the percentage of working class in the middle and high income countries. Thus, it can be said that India falls between low and middle income country categories at global level. So, government has to make efforts to provide health and education facilities to younger section of the population and also to make arrangements to train people who have reached the working age group.
Population pyramid: The tapering figure of the population based on age and sex is termed as population pyramid. An interesting way of studying the population Composition of a country is by studying the population pyramid.
(i) A country that has high birth rate and high death rate will have a population pyramid that is broad at the base and rapidly narrows towards the top.
(ii) This is because although a large number of children are born, a large percentage of them die in their infancy, few become adult and very few reach the old age.
(iii) For example, Kenya has a high birth rate, as well as a high death rate.
The Density of Population in India
(i) The number of people living in one unit area of the surface area is called population density. The average density of population in the world is 4 persons per sq. km.
(ii) India is one of the most densely populated countries of the world. The average density of population in India is 324 persons per sq. km. according to 2001 census.
(iii) One of the major facts regarding population density in India is that it has been consistently increasing over the years. In 1901, India’s population density was only 77 and it increased to 117 in 1951 and finally it has reached 324 in 2001.
(iv) In terms of density, there is great variation among different states in India. Union Territories of the Delhi and Chandigarh have the density of 9300 and 7900 persons per square kilometer respectively.
(v) Whereas, the density in Arunachal Pradesh and Mizoram is 13 and 43 persons per square kilometer respectively.
The social, cultural and economic impact on population distribution
(1) Social factors: Areas with better housing, education and health facilities are more populated than others.
(2) Cultural factors: Places with cultural and religious importance attract more people than others.
(3) Economic factors: Industrial areas are more populated as they provide employment opportunities.
Migration generally occurs from less developed regions to more developed regions in the search of employment. People also travel from the rural to urban areas due to better infrastructural facilities.