The world population Distribution, Density and growth
(Complete Notes)
chapter-2
Population denotes number of people living in an area on the earth. It is considered as an important asset of a nation. Population makes use of the country's resources and regulates its government through different policies and schemes for the welfare of the nation. The growth and distribution of the population depends upon various factors such as physical, social, economic and cultural.
Patterns of Population Distribution in the World
The way people are spread across the world is called population distributi The population in the world is unevenly distributed. About 10 per cent a of land is occupied by 90 per cent of the world population. Of this, abou 60 per cent population is residing in only 10 countries of the world and c these 10 countries, 6 countries are located in Asia, namely; China, India, Pakistan, Bangladesh, Russian Faderation and Japan.
Factors Influencing the Distribution of Population
There are three major factors which influence the population size and distribution in the world.
These are discussed below:
(i) Geographical/Physical Factors
Following are the geographical factors:
Availability of Water
Water is considered as life. It has many uses for human beings, such as in activities like drinking, bathing, cooking, for cattle, crops and also for industries and navigation purposes. Thus, river valleys are most densely populated areas of the world because of the availability of fresh water.
Landforms/Relief
Plain areas and gentle slopes always remained favourable for human settlements, because plains provide such relief which is suitable for cultivation of crops, to build roadways, railways and to set-up industries. Thus, plains are densely populated in the world.
Whereas, mountainous region provides obstacles in the path of industrial, agricultural and transport development. Thus, these are less favourable for human settlements. For example, the Ganga plains are one of the most densely populated regions in the world, whereas, the Himalayan region is sparsely (thinly) populated.
Climate
It has a direct impact on human beings. Humans prefer to live in normal climatic regions. Areas having harsh and extreme climates like regions with very heavy rainfall, very hot and very cold deserts are not favourable to live. People live in areas having less seasonal variations like near the coast or sea. For example, due to pleasant climate, Mediterranean regions are among most favourable places for human settlements since early periods of history.
Soils
People prefer to live in those areas which have fertile soils, as these are the base of agricultural development and allied activities.
For example, alluvial soil regions, black soil regions, etc. These soils support intensive agriculture and help in sustaining life.
(ii) Economic Factors
These include the following sub-factors:
Minerals Industries generally are set up in those areas which have abundance of mineral deposits. Industrial set up and mining activities generate employment opportunities
Thus, these areas are populated by semi-skilled and skilled workers. For example, Katanga Zambia copper belt in Africa.
Urbanisation Better employment opportunities, educational and medical facilities, better means of transport and communication, better civic amenities etc attract people to live in the cities. This leads to the process of migration from rural to urban areas. For example, mega cities like Delhi, Mumbai, Kolkata, etc are densely populated areas.
Industrialisation Industrial belts are vast regions which have industries that provide a number of job opportunities like transport operators, factory workers, shopkeepers, bank employees, teachers, doctors and other service providers.
For example, Kobe-Osaka region of Japan.
(iii) Social and Cultural Factors
These include the following sub-factors:
Cultural Significance
Culture and religion play an important role in human life. Places having social as well as cultural and religious significance attract people. People live community wise in these places.
Social and Political Unrest
Wars and conflicts often lead to out migration from place of origin to new place. Thus, it affects the distribution of population.
Government Incentives
Many a times government offer incentives to people to live in sparsely population areas or move away from overcrowded places.
Density of Population
Population density is important as it provides a deep analysis of population over a piece of land. It is important to know this because land has a limited capacity to sustain life.
The density of population is the ratio between the numbers of people living in a square kilometre of area.
It is usually expressed in persons per sq km.
Population Density of Population = population/Area
Population Growth or Change
It defines a change in number of people living in an area during a specific period of time. This change may be positive or negative. This is considered as an important indicator of economic development, social upliftment, historical and cultural background of a region. It can be expressed by two ways i.e. in in absolute numbers and in percentage.
Components of Population Growth
Generally, there are three important components of population change. These are birth, death and migration. The births and deaths in a region are measured by Crude Birth Rate and Crude Death Rate respectively.
(i) Birth Rate
There are various measures to calculate fertility/birth rate. But Crude Birth Rate (CBR) is most widely used as a measure of birth rate.
It is expressed as the number of live births in a year per thousand of population. It is calculated as Bi CBR = ×1000 P
Here, CBR = Crude Birth Rate Bi = Live births during the year P = Mid year population of the area
(ii) Death Rate
Like fertility/birth rate, death rate also plays an important role in population change. When death ra decreases, positive population growth takes place, whereas when death rate increases, negative populatic growth is recorded.
1. The simplest method to measure mortality of an area Crude Death Rate (CDR). It defines the number of Factors Affecting Mortality Rate
2. Mortality rates are affected by the region's demographic structure, social advancement and levels of its economic development.
3. Besides, epidemics, prolonged famines and floods lead to an increase in death rates, chronic diseases, government aided schemes, supply of Widespread immunisation against communicable and safe drinking water, urban sanitation, etc lead to a dramatic decline in death rates.
(iii) Migration
It is the third important component of population change. It is the movement of people from one place to another. Migrants who move into a new place are called immigrants. Migrants who move out of a place are called emigrants.
Components of Migration
Migration has the following two components:
(i) Place of Origin When people leave their home town, the place from where they leave is known as place of origin. This place records a decrease in population.
(ii)Place of Destination When people move to a new place, this place is known as place of destination. This place records increase in population.
Types of Migration
Migration may be permanent, temporary or seasonal. It may also take place in the following ways.
Rural to rural areas
Urban to urban areas
Rural to urban areas
Urban to rural areas
Factors of Migration
People migrate for a better social and economic life.
There are many factors influencing migration from one place to another such as:
Push Factors These factors are related to place of origin, where a number of reasons are responsible to push people to move to another place. For example unemployment, poor living conditions, political turmoil, unpleasant climate, natural disasters, epidemics and socio-economic backwardness.
Pull Factors These factors are related to place of destination which attracts people due to a number of reasons like better job opportunities and living conditions, peace and stability, security of life and property and pleasant climate.
Theory of Malthus
Thomas Malthus in his theory (1798) stated that the number of people would increase faster than the supply of food. If the population increases any further, it would result in a situation of population crash due to the existing famines, diseases and war. He stated that preventive checks are better than physical checks. Preventive checks reduce birth rates and it includes birth control measures, postponement of marriage etc.
For the sustainability of resources, the world will need to control rapid growth of population.
Demographic Transition Theory
The demographic transition theory is used to describe and predict the population and its growth in an area. The theory describes that the population in a region changes from high births and high deaths to low births and low deaths when:
A society which is rural and agrarian changes to an urban and industrial society.
1. A society where illiteracy is prevalent, changes to a literate society.
Rural, Agrarian, Illiterate Society
Demographic Transition
Urban, Industrial, Literate Society
Stages of Demographic Cycle
All these changes occur in different stages which are collectively known as the demographic cycle.
Stage I
🔹This stage occurred about two hundred years ago when all the countries of the world were in this stage.
🔹This stage is characterised by high fertility and high mortality rates. There are increasing deaths due to epidemics and variable food supply and people reproduce more to compensate it. There is slow growth of population.
🔹People mostly live in rural areas and their main occupation is agriculture. The large size of families is considered as an asset.
🔹Life expectancy is low due to epidemics and irregular from high births and high deaths to low births and low deaths when:
🔹Life expectancy is low due to epidemics and irregular food supply.
🔹This period has high prevalence of illiteracy and lack of technological advancement.
Stage II
🔹This is the period of time of population explosion.
🔹The fertility remains constantly high in the beginn but it declines with time.
🔹This period is characterised by reduced mortality This is due to an expansion in medical and health facilities and also improvements in sanitation food supply.
🔹This period has high prevalence of illiteracy and lack of technological advancement.
Stage III
🔹This stage is characterised by a decline in fertility and mortality rates.
🔹Birth rate is nearly equal to death rate and there is little growth in population.
🔹In this stage, population becomes more urbanised, literate and has high technical know how and deliberately controls the family size.
Thus, Demographic Transition Theory shows that human beings are flexible and are able to adjust their fertility. In the present day different countries are at different stage of demographic transition.
The graph above clearly shows high birth rate (CBR) as well as high death rate (CDR) on the Y-axis. Both high birth as well as high death rates leads to a stagnant population.
During stage II, the Birth rate is still high than the death rate and death rate starts declining. This leads to a rapid increase in population, which leads to high net addition in population.
In stage III, both birth as well as death rate is low. So there is very less growth in the population. The population growth becomes stagnant.
Population Control Measures
Family planning schemes can be implemented to control the ever rising population. Family planning is the spacing or preventing the birth of children. It also helps to improve women's health. The government should provide access to such services. Other important measures are propaganda, free availability of contraceptives and tax disincentives for large families which make people aware about population control.
🟢 Self assessment
SHORT ANSWER TYPE QUESTIONS
1 What is the effect of climate on population distribution?
2 Distinguish between immigration and emigration.
3 In spite of having an attractive life, cities are places where newly migrated people face a lot of difficulties. Explain the reasons.
4 Positive population growth leads to a number of problems. Explain.
5 Which situations push a person to leave his/her hometown to move to a new place? Elaborate the reasons.
LONG ANSWER TYPE QUESTIONS
1 Discuss the factors which influence the distribution of population.
2 Explain the economic consequences of migration.
3 How is population of the world distributed?
4 Why do developing nations always face situation of population explosion?