Density & Population Growth| Class 12 Geography Notes

The greatest source of wealth for a nation is said to be its people. The people of a country have a major role in deciding its socio-economic position in the world. It is the people of a nation who use their country’s resources for its development and decide on policies to help govern a nation better. Therefore a large population is advantageous if used well by a government.

It is important to learn important factors associated with population and this article aims to give simplified notes for students on the topic of Density and Growth of population, as discussed in Chapter 2 of the helpClass 12 Geography NCERT book. Please go through this article for better understanding of this topic and easy-to-read notes.

Population Density

• Patterns of population density help us understand the demographic characteristics of any area. It is important to note that each unit of land can only support a limited number of people efficiently. To learn about the demography of an area better, it is essential to note the population density of that area.
• Population density is the ratio between the number of people to the area of the land. It is measured in persons per square kilometer or km².

Important note: The distribution of population across the globe is not uniform aka the way people are spaced over the surface of the earth is not even. 90% of the world’s population is said to live in approximately 10% of the earth’s land area, indicating uneven usage of resources and uneven socio-economic development across nations.

Density of population = Total Population / Total Area

• The table below gives us a few examples of densely and sparsely populated regions across the globe for a better understanding of population density:

Population Density	Description	Examples across the globe
Densely populated areas	More than 200 persons per sq. km.	North -Eastern part of U.S.A., North-Western part of Europe, South, South-East and East Asia
Medium density areas	Approx. 11 to 50 persons per sq. km.	Western China, Southern India in Asia, Norway, Sweden in Europe etc.
Sparsely populated areas	Less than 01 person per sq. km.	The North and South Poles, the hot and the cold deserts and high rainfall zones near the Equator.

• The population density of India in 2011 was 382 per sq. km.

Factors Affecting Population Density

Various geographical, economic and socio-cultural factors affect the distribution of population, which directly affects the population density of an area; These are as follows:

1. Geographical Factors

S.No.	Geographical Factors	Explanation
1.	Water availability	People prefer to reside in areas that have water in abundance and is available easily, as water is the most essential component for survival for everyone. Water is used for multiple purposes like cooking, drinking, agriculture, etc., therefore we find that river valleys are among the most densely populated areas of the world.
2.	Landforms	People prefer living on flat plains and gentle slopes, which are favorable for agricultural purposes, to build better road connectivity and for industries, as opposed to mountainous and hilly areas, that pose big obstacles for smooth transportation and agriculture. Therefore the Ganga Plains are one of the most densely populated areas of the world while mountainous regions of the Himalayas are thinly populated.
3.	Climate	A place with balanced, pleasant climate i.e. which is neither too hot nor too cold attracts more people. This is why Mediterranean regions were inhabited from early periods in history due to their comfortable climate. Areas with very heavy rainfall or extreme and harsh climate have low population density.
4.	Soil	People prefer to live in areas with fertile, loamy soils as this type of soil supports intensive agriculture. Areas that have infertile soil lands are comparatively less populated.

2. Economic Factors

S.No.	Economic Factors	Explanation
1.	Minerals	Areas with rich mineral deposits attract industries which in turn generate employment opportunities. Skilled and semi-skilled workers flock to such places and make them thickly populated. For example, Katanga Zambia copper belt in Africa.
2.	Urbanization	Urban centers or cities offer better employment opportunities, educational and medical facilities, better means of transport and communication. This leads to rural to urban migration and cities becoming densely populated.
3.	Industrialization	Industrial areas provide better job opportunities and attract huge number of people like factory workers, transport operators, shopkeepers, bank employees, doctors, teachers and other service providers. This is why the Kobe-Osaka region of Japan is densely populated due to the presence of a large number of industries.

3. Social and Cultural Factors

Some places attract more people because they have religious or cultural significance. People tend to move away from places that have social and political unrest. Sometimes the government offers incentives to people to move to thinly populated areas or move away from overcrowded places.

Population Growth

• Population growth means the change in the number of inhabitants of an area over a specific period of time. This change may be positive as well as negative.
• The change can be expressed either in terms of absolute numbers or in terms of percentage.
• Population change is indicative of the economic development, social upliftment and historical and cultural background of an area.

Some Basic Concepts of Population Geography

Growth of population	Refers to the change of population in a particular area between two points of time.
Growth rate of population	Change in population expressed in terms of percentage is the growth rate of population.
Natural growth of population	It is the population increase because of the difference between births and deaths in a particular region between two points of time aka Natural Growth = Births – Deaths.
Actual growth of population	Actual Growth = Births – Deaths + In Migration – Out Migration.
Positive growth of population	This occurs when the birth rate is more than the death rate between two points of time or when people from other countries migrate permanently to a region.
Negative growth of population	This occurs when the population decreases between two points of time, either when the birth rate falls below the death rate or people migrate to other regions.

Components of Population Change

Births, deaths and migration are the are three components of population change.

1. Crude Birth Rate (CBR)

• It is expressed as number of live births in a year per thousand of population. It is calculated as:

CBR=Bi/P×1000

Where, Bi= live Births during the year; P = Mid year population of the area.

2. Crude Death Rate (CDR)

• CDR is a simple method of measuring mortality of any area, as death rate plays a major role in population change.
• It is expressed in terms of the number of deaths in a particular year per thousand of population in a particular region. It is calculated as:

CDR=D/P×1000

Here, D= Number of Deaths; P= Estimated mid-year population of that year.

3. Migration

• Migration aka movement of people across region also changes the population size of an area.
• The movement of people can be permanent or seasonal.
• The area people move from is called place of origin and the area people move to is called place of destination;
• People mostly migrate for better employment opportunities and living conditions.

Factors that Influence Migration

Factors affecting Migration	Explanation
Push factors	Push factors make the place of origin seem less attractive/ less livable due to like unemployment, poor living conditions, political turmoil, unpleasant climate, natural disasters, epidemics and socio-economic backwardness.
Pull factors	Pull factors make the place of destination seem more attractive/ more livable than the place of origin for reasons like better job opportunities and living condition peace and stability, security of life and property and pleasant climate.

Trends in Population Growth

• The population across the globe has grown in size over centuries. During the earlier periods the population growth across the world was very slow. The world population skyrocketed in the 18th century after the Industrial Revolution.
• Research has shown that every 12 years, 1 billion people are added. Increased agriculture and industrial production, improvement in medical facilities and technology have reduced death rates leading to exponential population growth.
• Listed below are some interesting trends in population growth:

Doubling Time of World Population	Research has found that developed countries are taking more time to double their population as compared to developing countries. Oman, Saudi Arabia, Somalia, Liberia, Yemen have high population growth rates. Latvia, Estonia, Russia, Germany, etc have low growth rates.
Spatial Pattern of Population Change	The world population growth rate is 1.4%, it is highest in Africa i.e. 2.6% and lowest in Europe i.e. 0.0% means neither grow nor decline, indicating that there is negative correlation between economic development and population growth. When a small annual rate is applied to very large population, it will lead to a large population change.

Impact of Population Change

• Although a small increase in population is favored in a growing economy, high increase in population leads to problems like depletion of natural resources, unemployment and scarcity.
• Decline in population indicates that resources are insufficient to maintain a population.

People Also View:

• Population Growth
• Population Attributes
• Population Growth and Process of Population Change
• Distribution of Population: Facts & Figures

Conclusion

Population density and growth depend on various factors as we have discussed above. In order to properly understand population as a concept and terms related to it, it is essential that everyone is aware of all the components that make up the population. The biggest wealth of a country is its people, therefore it is crucial that more research needs to be conducted on the topic of population to keep up with modern advancement and its impact on population growth.

Chapter 2 Density & Population Growth- FAQs

Which state has lowest population density in India?

Arunachal Pradesh is the state with lowest population density of just around 13 per square km (2011 census).

What is the unit of population density?

Population density is the average number of people per unit of land area. The most common unit of population density is persons per square mile/km.

Which state in India has the highest population density as per Class 12 geography?

The state with the highest population density in India is Bihar.

Which country has highest population density?

With a population density of 21,054 per square kilometer, Macao in China was the most densely populated country in the world in 2021.

Which factors affect population density?

Topography, Climate, Soil, Water, Minerals, Social factors like Health and education facilities, Industries or Economic activities and cultural activities can affect the population density of a country.