Notes Class 12 Chapter 1 Geography महाराष्ट्र Board

Population : Part – 1

Introduction

• Geography studies how humans interact with their environment.
• Population Geography, a branch of Human Geography, focuses on:
• Human population: Numbers, distribution, and patterns across the Earth.
• Qualitative and quantitative aspects: Characteristics like age, sex, education, and occupation.
• Impact on economy and development: How population influences a region’s growth.

In this chapter, humans are studied as a resource that shapes and is shaped by the environment.

1. Distribution of Population

The world’s population in 2019 was approximately 7.7 billion.
Population is unevenly distributed across continents due to various factors.

Continent-wise Population and Landmass (2019 Data)

Population Density

Definition: Number of people living per unit area (usually per square kilometer).
Formula:

• Helps understand how crowded or sparse a region is.
• Example: Asia has high density due to a large population in a relatively smaller land area.

Using the data for the 10 most populated countries in 2018, calculate density:

Observation:

• Bangladesh has the highest density (1073.33 people/sq. km) due to a large population in a small area.
• Russia has the lowest density (8.54 people/sq. km) due to a vast area with a smaller population.

2. Patterns of Population Distribution

Population distribution refers to how people are spread across the Earth’s surface (see Fig 1.2).
Key Observations:

• High-density areas: Coastal plains, river valleys (e.g., Ganges, Nile), and fertile lands.
• Low-density areas: Deserts, snow-covered regions (e.g., Arctic), forests, and mountainous areas.
• Population density varies due to physical and human factors.

Physical Factors Affecting Population Distribution

Human Factors Affecting Population Distribution

Other Factors

• Distance from the sea: Coastal areas are densely populated due to trade and transport (e.g., Mumbai, New York).
• Natural harbors: Attract settlements (e.g., Singapore).
• Energy sources: Areas with coal, oil, or hydropower attract industries (e.g., Manchurian region, China).
• Migration: Movement of people due to jobs or conflicts affects density.
• Technology: Advanced technology supports settlement in harsh areas (e.g., oil fields in Saudi Arabia).

3. Components of Population Change

• Population change: Change in the number of people in an area over time, expressed as:
• Absolute numbers (e.g., population increased by 1 million).
• Percentage (e.g., population grew by 2%).

Population change can be positive (growth) or negative (decline).
Three components:

1. Births: Number of live births.
2. Deaths: Number of deaths.
3. Migration: Movement of people in or out of an area.

Crude Birth Rate (CBR)
Definition: Number of live births per 1,000 people in a year.
Formula

Crude Death Rate (CDR)
Definition: Number of deaths per 1,000 people in a year.
Formula

Population Growth
Formula:

Population Growth = Present Population – Earlier Population
Growth Rate:
Impact of Birth and Death Rates:

• Births > Deaths: Population increases.
• Deaths > Births: Population decreases.
• Births = Deaths: Population remains stable (rare).

Arrange countries by Crude Birth Rate (CBR) and Crude Death Rate (CDR) (2017 data):

Ascending Order:

CBR: Greece (8.2), Sweden (11.5), USA (11.8), China (12.4), India (18.1), Niger (46.5).
CDR: China (7.1), India (7.2), Niger (8.5), USA (8.5), Sweden (9.1), Greece (11.6).

4. Demographic Transition Theory

Explains how population growth changes with economic development.
Countries pass through five stages based on birth rates and death rates (see Fig 1.7).

Stages of Demographic Transition