Human Geography 101: Population Geography - Demographic Transition Model Stage 15 Births Deaths Natural Increase

What This Is

The Demographic Transition Model (DTM) is a five-stage model that explains how population growth is linked to economic development. It matters for understanding why some countries still have high birth rates, while others have low birth rates. For example, in the 1960s, India's population growth rate was high due to a high birth rate, but after implementing family planning policies, the birth rate decreased, and the population growth rate slowed down.

Key Models, Theories & Terms

• Demographic Transition Model (DTM): A five-stage model linking population growth to economic development (Stage 1: high CBR & CDR-… Stage 4: low CBR & CDR) – explains why some countries still have high birth rates.
• Von Thünen’s Model of Agricultural Land Use: Concentric rings around a city (dairy, forest, grains, livestock) determined by transportation costs – explains where different crops are grown.
• Carrying Capacity: The maximum population size that an environment can support – explains why some areas are overpopulated.
• Population Pyramid: A graphical representation of a population's age and sex structure – explains the age structure of a population.
• Total Fertility Rate (TFR): The average number of children a woman would have in her lifetime – explains the fertility rate of a population.
• Crude Birth Rate (CBR): The number of live births per 1,000 people in a population per year – explains the birth rate of a population.
• Crude Death Rate (CDR): The number of deaths per 1,000 people in a population per year – explains the death rate of a population.
• Natural Increase: The difference between the birth rate and death rate – explains the population growth rate of a population.
• Population Momentum: The tendency of a population to continue growing due to the large number of people in the reproductive age group – explains why some populations continue to grow even if the birth rate decreases.

Step-by-Step Application

1. Identify the stage of the Demographic Transition Model (DTM) that a country is in by analyzing its birth and death rates.
2. Use a population pyramid to analyze the age structure of a population and identify the stage of the DTM.
3. Calculate the Total Fertility Rate (TFR) and Crude Birth Rate (CBR) to understand the fertility rate of a population.
4. Analyze the Crude Death Rate (CDR) to understand the death rate of a population.
5. Calculate the Natural Increase to understand the population growth rate of a population.
6. Use the concept of population momentum to explain why some populations continue to grow even if the birth rate decreases.

Common Misconceptions

• Misconception: All migration is permanent.
• Correction: Not all migration is permanent; some people may migrate temporarily for work or education.
• Example: Seasonal migration of farmworkers in the United States.
• Misconception: GDP per capita is the same as standard of living.
• Correction: GDP per capita is an economic indicator, but it does not necessarily reflect the standard of living, which also depends on factors like access to education and healthcare.
• Example: A country with a high GDP per capita may still have a low standard of living due to income inequality.
• Misconception: Rank-size rule applies to every country.
• Correction: Rank-size rule applies to cities with a high degree of central place theory, but it does not apply to all countries or cities.
• Example: The rank-size rule applies to cities in the United States, but not to cities in countries with a more decentralized economy.

AP Exam / Free-Response Tips

• When answering FRQs, make sure to identify the task verb (e.g., identify, describe, explain, compare) and use the correct geographical terminology.
• When integrating models into essays, make sure to explain how the model applies to the specific case study.
• Be aware of tricky distinctions like ethnicity vs nationality, site vs situation, and centripetal vs centrifugal forces.
• Use specific examples from real-world cities, countries, and cultural processes to support your arguments.

Quick Practice Scenario

A megacity in a developing country grows rapidly as rural residents move in for factory jobs. Identify the dominant migration pattern and one likely urban model that describes its structure.

Answer: The dominant migration pattern is urbanization, and one likely urban model that describes its structure is the Burgess concentric zone model.

Explanation: The Burgess concentric zone model describes the growth of a city in a series of concentric zones, with the most affluent residents living in the inner city and the least affluent residents living in the outer suburbs.

Last-Minute Cram Sheet

• The Demographic Transition Model (DTM) has five stages: high birth and death rates, high birth rates and low death rates, low birth rates and low death rates, low birth rates and high death rates, and low birth and death rates.
• Von Thünen's Model of Agricultural Land Use describes the concentric rings around a city determined by transportation costs.
• Carrying capacity is the maximum population size that an environment can support.
• Population momentum is the tendency of a population to continue growing due to the large number of people in the reproductive age group.
• Total Fertility Rate (TFR) is the average number of children a woman would have in her lifetime.
• Crude Birth Rate (CBR) is the number of live births per 1,000 people in a population per year.
• Crude Death Rate (CDR) is the number of deaths per 1,000 people in a population per year.
• Natural Increase is the difference between the birth rate and death rate.
• Population pyramid is a graphical representation of a population's age and sex structure.
• Ethnic religion (Judaism, Hinduism) is not the same as universalizing religion (Christianity, Islam, Buddhism) – ethnic religions do not actively seek converts.
• GDP per capita is not the same as standard of living – GDP per capita is an economic indicator, but it does not necessarily reflect the standard of living.