Overview of Population

• India’s Population Share – India has only 2.4% of the world’s land but supports about 17.5% of the world’s population.
• Most Populous Country – India became the most populous country in the world in 2023, surpassing China.
• Population in 2024 – India’s total population was about 143.8 crore in 2024.
• Comparison with Other Countries – The USA, the third most populous, has 4.5% of the world’s population; Canada and Australia have less than 1% each.
• Census in India – Population data are collected every 10 years; the first full census was in 1881; the 2011 census was the 15th overall and 7th after Independence.

• Uneven Distribution – India’s population (1210 million in 2011) is unevenly distributed; Uttar Pradesh has the highest population.
• Large vs Small States – Big area does not mean big population (e.g., Rajasthan large area but less population; UP small area but very high population).
• Population Density (2011) – 382 persons per sq. km.; density has increased continuously since 1921.
• High Density Areas – Bihar (1102), West Bengal, Uttar Pradesh, Kerala and Delhi have very high population density.
• Low Density Areas – Arunachal Pradesh, Sikkim, Jammu & Kashmir and other hilly states have low density due to difficult terrain.
• Causes of Variation – Relief, climate, soil, water supply, urbanisation, industrialisation and migration affect population density.
• Types of Density –
  i. Arithmetical: Total population ÷ total area
  ii. Physiological: Total population ÷ cultivated land
  iii. Agricultural: Agricultural population ÷ cultivable land

• Index of Concentration – It shows the percentage share of a state’s population in India’s total population (e.g., U.P. had about 19.5% in 2011).
• Uneven Distribution – Population is highly concentrated in plains, urban and industrial areas, while mountains, deserts and forests have low population.
• Physical Factors – Terrain, climate (rainfall & temperature), soil and water availability strongly affect population density.
• Economic Factors – Minerals, industries and transport facilities attract people and increase population density.
• Urbanisation – Urban centres have very high population density due to employment and better facilities.
• Types of Growth –
  i. Natural growth = Birth rate – Death rate
  ii. Migratory growth = Change due to migration
  iii. Positive/Negative growth depends on increase or decrease in population.
• Population Trend in India – India has mostly shown positive growth since 1872; 1921 was the only year of negative growth.

• Four Phases of Population Growth –
  1901–1921: Stagnant growth (1921 called demographic divide)
  1921–1951: Steady growth
  1951–1981: Rapid high growth
  1981–2011: High growth but slowing down
• Demographic Divide (1921) – Population declined slightly due to epidemics, famines and World War I deaths.
• Rapid Growth (1951–1981) – Population almost doubled due to fall in death rate and improvement in health and living conditions.
• Slowing Growth After 1981 – Birth rate declined; growth rate reduced to 1.76% in 2011, showing success of family planning.
• Regional Variations – States like Bihar and Meghalaya have high growth; Kerala has very low growth; some small UTs show very high growth.
• Impact on Development – Fast population growth increases poverty, unemployment, housing shortage, illiteracy and pressure on basic facilities.
• Environmental & Ecological Impact – Overuse of land, forests and minerals causes pollution, soil degradation, loss of biodiversity and ecological imbalance.

\[\text{Arithmetical density}=\frac{\text{Total Population}}{\mathrm{Total~Area}}\]

\[\text{Physiological density}=\frac{\text{Total population}}{\text{Net cultivated area}.}\]

\[\text{Agricultural density}=\frac{\text{Total agricultural population}}{\text{Net cultivable area}}\]