Overview of Population : Part - 1

Population density is the number of people living in a particular area per square kilometre.

\[\begin{aligned}
 & \text{Density of population}=\frac{\text{Total population}}{\text{Total area (in sq. km.)}}
\end{aligned}\]

• Population Geography studies people, their numbers, and where they live in the world.
• In 2019, the world population was about 7.7 billion, and it is not evenly spread.
• Asia has the largest population (around 60%), though it has about 30% of the land.
• North and South America together have about 28% land but only 18% population.
• Antarctica has land but no permanent population.

• Population distribution means how people are spread over the Earth’s surface.
• Population and population density are unevenly distributed across the world.
• Snow-covered regions near the North and South Poles are sparsely populated.
• Hot deserts, mountains, and hilly areas have low population.
• Coastal areas and plains are densely populated, while thick forests (like the Amazon Valley) have less population.

• Relief (Landforms): Plains and gentle slopes are densely populated because they are suitable for farming, transport, and industries. Mountains and plateaus are less populated.
• Climate: Areas with moderate (equable) climate attract more people. Very hot, cold, or heavy rainfall regions have low population.
• Water Availability: People prefer to live near rivers, lakes, coasts, and oases because water is essential for life. River valleys like the Nile and Ganga are densely populated.
• Soil Fertility: Fertile soils support agriculture, so floodplains and volcanic soil regions have high population density.
• Risk Factors: Though volcanic regions have fertile soil and high population, volcanic eruptions can cause serious damage and loss of life.

• Agriculture: Improved farming methods, irrigation, and fertilisers increase food production and support more population.
• Mining and Industries: Areas rich in minerals attract industries and workers, leading to a dense population.
• Transportation: Good road, rail, and sea transport increases accessibility and population density, especially in port cities.
• Urbanisation: Growth of industries and services leads to the development of cities, offering better jobs, education, and healthcare.
• Government Policies: Government decisions and incentives can encourage or discourage population settlement in certain areas.

• Population Change means an increase or decrease in the number of people in a region over a period of time.
• Population change can be positive (growth) or negative (decline).
• There are three main components of population change: births, deaths, and migration.
• Crude Birth Rate shows the number of live births in a year per thousand people.
• Crude Death Rate shows the number of deaths in a year per thousand people.

\[CBR=\frac{\text{Total number of live births in a year}}{\text{Total population in that year}}\times1000\]

\[CDR=\frac{\text{Total number of deaths in a year}}{\text{Total population in that year}}\times1000\]

Population Growth = Present Population - Earlier Population

\[\text{Population}\text{growth rate}=\frac{\text{Population growth}}{\text{Earlier population}}\times100\]

• Birth rate and death rate together decide whether the population will grow, stay stable, or decline.
• Demographic Transition Theory explains that every country passes through different stages of population change over time.
• Stage 1 (High Stationary): Birth rate and death rate are both high, so population growth is almost stable.
• Stage 2 (Early Expanding / Population Explosion): Death rate falls but birth rate stays high, so population increases very fast.
• Stage 3 to 5 (Growth slows): Birth rate starts decreasing; in Stage 4, growth is very low, and in Stage 5, the population may experience zero growth or decline (more old people, fewer children).