The World Population Distribution Density and Growth
1. Patterns of Population Distribution
- The core principle: The people of a country are its real wealth and actual resources.
- Uneven Distribution: About 90% of the world’s population lives in only about 10% of its land area.
- Top Heavy: The 10 most populous countries account for roughly 60% of the world’s population, and 6 of these countries are in Asia.
- George B. Cressey’s Observation: “Asia has many places where people are few and few place where people are very many,” which also accurately describes global population patterns.
2. Density of Population
- Definition: The ratio between the number of people and the size of the land they occupy, usually measured in persons per square kilometer.
- Formula: Density of Population = Population ÷ Area.
- Example: If Region X has an area of 100 sq km and a population of 150,000, the density is 1,500 persons/sq km.
3. Factors Influencing Population Distribution
I. Geographical Factors
- Availability of water: People settle where fresh water is available for drinking, agriculture, and industry. River valleys are among the most densely populated areas.
- Landforms: Flat plains and gentle slopes are preferred for crops, roads, and industries (e.g., densely populated Ganga plains). Mountainous regions (like the Himalayas) hinder transport and are scarcely populated.
- Climate: Extreme climates (very hot or cold deserts) are avoided. Pleasant climates with moderate seasonal variation, like the Mediterranean regions, attract human habitation.
- Soils: Areas with fertile loamy soils support intensive agriculture and attract more people.
II. Economic Factors
- Minerals: Mining generates employment, attracting skilled and semi-skilled workers. Example: Katanga Zambia copper belt in Africa.
- Urbanisation: Cities offer better employment, education, medical facilities, and transport, leading to rural-urban migration.
- Industrialisation: Industrial belts create jobs for factory workers, shopkeepers, doctors, and transport operators. Example: The thickly populated Kobe-Osaka region in Japan.
III. Social and Cultural Factors
- Places with strong religious or cultural significance attract people.
- Social and political unrest pushes people away.
- Governments sometimes offer incentives to encourage people to settle in sparsely populated regions or leave overcrowded ones.
4. Population Growth and Change
- Growth of Population: The change in the number of inhabitants in a specific area between two points in time. It can be expressed in absolute numbers or as a percentage.
- Natural Growth: Measured by subtracting the number of deaths from the number of births (Births – Deaths).
- Actual Growth: Calculated as: Births – Deaths + In-Migration – Out-Migration.
- Positive Growth: Occurs when the birth rate is higher than the death rate, or when permanent migration into the region happens.
- Negative Growth: Occurs when the population decreases, either because the birth rate falls below the death rate or due to emigration.
Measuring Births and Deaths:
- Crude Birth Rate (CBR): Number of live births in a year per thousand of the population. Calculated as $CBR = (Live_Births ÷ Population) \times 1000$.
- Crude Death Rate (CDR): Number of deaths in a year per thousand of the population. Calculated as $CDR = (Deaths ÷ Population) \times 1000$. Mortality rates are heavily influenced by the region’s demographic structure and economic development.
5. Migration
- Terminology: The Place of Origin (where people leave) shows a decrease in population, while the Place of Destination (where people go) shows an increase.
- Immigrants: Migrants moving into a new place.
- Emigrants: Migrants moving out of a place.
- Push Factors: Reasons that make a place less attractive (e.g., unemployment, poor living conditions, political turmoil, natural disasters, epidemics).
- Pull Factors: Reasons that make a destination attractive (e.g., better job opportunities, good living conditions, peace, stability, pleasant climate).
6. Demographic Transition Theory
This theory describes how a region’s population changes from high births and high deaths to low births and low deaths as society progresses from rural/agrarian to urban/industrial.
- Stage I: Characterized by high fertility and high mortality. People have large families to compensate for high death rates from epidemics and unstable food supplies. The society is mostly illiterate, agricultural, and has low life expectancy.
- Stage II: Fertility initially remains high but eventually declines. Improved sanitation and healthcare lead to a significant drop in mortality. Because birth rates outpace death rates, the net addition to the population is high.
- Stage III: Both fertility and mortality decline considerably. The population grows slowly or stabilizes. Society is urbanized, highly literate, technologically advanced, and deliberately controls family size.
7. Population Control Measures
- Family Planning: Access to contraceptives and spacing births helps limit population growth and improves women’s health. Governments may use propaganda or tax disincentives for large families.
- Thomas Malthus’s Theory (1798): Malthus predicted that human population would increase much faster than the food supply. If left unchecked, this would result in a population crash caused by physical checks like famine, disease, and war. The theory argues that preventive checks are necessary for resource sustainability.