Population Change

All people together constitute a nation. In simpler terms, population change is the change in the number of people at a specific location in a given period. This time period could either be a year, a decade, or even a century. This research on population change can bring both positive and negative results. This change can be defined in various metrics such as numbers and percentages. It is also an indicator of socio-economic development in an area and the cultural background. Officially, 90 percent of the world population lives on around 10 percent of the total world area.

How is the density of a population calculated?

Every land has a limited capacity of people it can sustain. This capacity is measured as persons per sq km and is known as the density of a population.

Density of population = Population/Area

In some regions such as Canada and Australia, the density is less than one person per sq km, while in the USA and Europe, it ranges from 11-50 people per sq km. In the subcontinent, this goes beyond 200 people per sq km.

How is the population change calculated?

There are two ways to calculate this population change: Natural and Actual.

Natural = Births – Deaths

Actual = Births – Deaths + In Migration – Out Migration

The population growth rate and change can be understood using the above formulas. Various factors affect the population change.

What factors lead to population change?

1. Geographical Factors :
   • Landmass: It has been found that people prefer living in plain landmass because crop production and infrastructure construction is easier and more favourable here than in other locations. This involves roads, industries and houses. Whereas mountainous or hilly areas prove to be difficult for infrastructure. This is why the Ganga plains is one of the most densely populated regions.
   • Climate: Another critical factor is climate. Places that have extreme weather conditions prove to be uncomfortable for inhabitants. In contrast, places with normal weather and comfortable conditions attract many people.
   • Water and Soil: Freshwater availability is still the main concern for a large population. Thus, people opt to move to places where water is easily available, and the soil is fertile enough for crop production.

2. Economic Factors :
   • Industries: Places with mineral deposits or other essential resources attract industries. These industries then generate employment in large numbers, which leads to workers relocating to the industry’s location. Ex – Katanga Zambia CopperBelt in Africa.
   • Urbanisation: City life offers better living standards, better employment opportunities, educational and medical facilities and better civic amenities. All these lifestyle upgrades attract more people to the city. Thus, many people from rural areas migrate to urban areas.
   • Employment: The most common reason for migration is employment. People move from one place to another in search of better opportunities.

3. Social and Cultural Factors: Some places hold powerful social and cultural significance. Similarly, people also move if the region has constant social and political unrest.

What are the impacts of population change?

Many of the varying impacts of population change are :

• A high rate of population growth can cause a negative impact on natural resources.
• The environment gets badly affected by the rise in population.
• Depletion of resources can lead to problems in the coming times.
• Cost of living of the masses increases.
• Positive change is that it affects economically at a more significant level.
• Tax bases get expanded.
• Spending at business (local or higher level) increases.

What are the types of population change?

There are two types of population changes, namely positive and negative.

Positive: When there is an increase in the population at a specific location in a given period, it is termed a positive growth rate. This happens when the number of births is higher than death or when people permanently migrate in that specific region.

Negative: If the population decreases at a given point of time at a specific location, then it is termed a negative growth rate. It happens when the birth rate falls, and the death rate rises or when people shift permanently to a new place.

Demographic Transition Model and Population Change:

This theory tells us how the population of a region, area wise population changes and also predicts the future. There are three stages to this theory :

• First stage: High fertility and high mortality. The population growth rate is very timid, and people are engaged in agricultural activities. Life expectancy is low as well, and most people are illiterate.
• Second stage: Initially, the fertility rate is high but declines as time passes. Similarly, mortality is reduced too. Sanitation and healthcare facilities lead to the net addition of population.
• Third stage: Fertility and mortality rate are at a declining level. Population size could either be growing or become stable. Meanwhile, the population becomes literate and urbanised while the technology level rises.

Presently, various regions in the world are going through different stages of this demographic transition model.

Conclusion

The difference in the number of population is termed as population change. These can be either positive or negative. Many factors contribute to this change, leading to broader impacts on the environment and the world.