Population Distribution, Density, and Growth

Population Distribution and Density

• 2.1 Environmental and Human Factors: Climate, landforms, bodies of water, culture, economics, history, and politics influence population distribution.
• 2.2 Population Density: Methods to calculate population density include arithmetic, physiological, and agricultural density.
  • These methods reveal different information about the pressure a population exerts on the land.

Population Distribution

• Population distribution is the pattern in which humans are spread out on Earth's surface.
• The world population is 7.96 billion people.
  • The majority live in metro areas, which are relatively small areas.
  • Much of Earth's surface is sparsely populated, resulting in uneven distribution.
• Where Humans Live:
  • 6.8 billion in the Northern Hemisphere.
  • Most live in mid-latitudes (between 30 and 60 degrees north and south).
    • This accounts for approximately ⅔ of the population.
  • Areas with easy access to water (oceans and rivers).
  • Eurasia: Europe (just under 10% of the human population) and Asia (almost 60% of humanity) account for 70% of the world's population.
• Ecumene: the portion of Earth with permanent human settlement, which has expanded during history.

Population Clusters

• Population clusters are heavily populated areas illustrating unevenness in global population distribution.
  • 2/3rds of the total population live on less than 20% of the land.
• Four Major Clusters:
  • South Asia
  • East Asia
  • Europe
  • Southeast Asia

South Asia

• Largest of the four clusters.
• Densely populated near the Indus, Ganges, and Brahmaputra rivers.
• Metacities: Cities with more than 20 million inhabitants.
  • Delhi, India; Karachi, Pakistan
• Megacities: Cities with more than 10 million inhabitants.
  • Mumbai, India; Dhaka, Bangladesh

East Asia

• China: Was the world’s most populous country (1.44 billion).
  • The government struggles to meet education, jobs, and housing needs, leading to the One Child Policy in the 1970s.
  • Farmable land is very populated.
• Moist and mild climate with fertile soil and coastal areas result in high population density.
• Korea and Japan are densely populated.
• Declining population due to a high elderly population, leading to labor shortages and a social burden in the future.

Europe

• (No specific information provided in the transcript excerpt.)

Southeast Asia

• Indonesia and the Philippines.
  • Indonesia is the 4th most populated country in the world.
• Primarily rural populations with low development.

Population in Countries (2018 Data)

• Table 7.1: The World's 10 Most Populous Countries, 2018 and 2050 (Estimated)
  2018:
  * China: 1,394 million
  * India: 1,371 million
  * United States: 328 million
  * Indonesia: 265 million
  * Brazil: 209 million
  * Pakistan: 201 million
  * Nigeria: 196 million
  * Bangladesh: 166 million
  * Russia: 147 million
  * Mexico: 131 million
  2050 (Estimated):
  * India: 1,680 million
  * China: 1,344 million
  * Nigeria: 411 million
  * United States: 390 million
  * Indonesia: 320 million
  * Pakistan: 306 million
  * Brazil: 231 million
  * Democratic Republic of Congo: 216 million
  * Bangladesh: 202 million
  * Ethiopia: 191 million

Population Shifts

• Uneven distribution leading to population shifts.
• Snow Belt: Northern and Midwestern parts of the country.
• Sun Belt: Coastal areas and the South and Southwest (California to Florida).
  • The Snow Belt is decreasing in population as people move to Sun Belt areas.
• Mean Center of Population: The balancing point given the distribution of population.
  • Gradually moving west from Maryland since 1790 and then southwest by 1920.

Sparsely Populated Areas

• More spaces are unpopulated than densely populated.
• Due to the "5 TOO’s": too hot, too cold, too dry, too wet, too hilly/mountainous.
• Examples:
  • Most of the Russian population live in the west because the tundra climate of interior/eastern Russia is too cold to support a large population.
  • North Africa/Arabian Peninsula = too dry.
  • North America/North Eurasia…?
  • Amazon Basin…?
  • Australia = too dry.

Physical Factors Affecting Population Distribution

• Elevation:
  • People prefer lower elevations to escape colder weather.
  • In South America (tropics), people live in mountain valleys and basins (e.g., temperate Andes Mountains) to escape heat.
• Bodies of Water:
  • People in Australia, Eurasia, and South America live on the periphery = advantages of trade (near ports), fishing opportunities, moderate climate change, and access to transportation.
  • Inland bodies of water = advantages of transportation, irrigation for agriculture, fertile soil.
• Climate:
  • Difficult climates (5 TOO’s) = sparsely populated.
  • People prefer humid tropics, subtropics, midlatitudes (30-60).
• Disease:
  • Push factor, causing people to leave.
  • Disease affects livestock, which then affects the production of clothes and food supply, so people move elsewhere.

Human Factors Affecting Population Distribution

• Culture:
  • Cultural groups' perception of the environment.
    • Germans prefer the shady high side for cows, while Italians prefer the sunny lower side for crops.
  • Big families keep or draw people places.
• Economic Development:
  • Before the Industrial Age, coalfields were sparsely populated; then steam-powered engines created demand for coal, attracting people for jobs.
• Political:
  • Military base at the northern edge of Canada during the Cold War.

How to Count Population Density

• Population Density: The average number of people per unit of land area.
  • Tells how crowded a place is and the relationship between the population and the environment.
• Three Ways to Calculate Population Density:
  • Arithmetic/Crude Density
  • Physiological Density
  • Agricultural Density

Arithmetic/Crude Density

• The average number of people per unit of land area.
  • Arithmetic Density = (Total Population) / (Total Land Area)
• Can be misleading because it doesn’t show uneven population distribution within a country.
• Example: Country A has a densely populated coastal area, and Country B has flat land with an evenly distributed population, but both have the same arithmetic density.

Physiological Density

• The average number of people per unit area of arable land.
  • Large countries with little arable land = higher physiological density than arithmetic density.
  • Physiological Density = (Total Population) / (Total Arable Land Area)
  • Can exceed carrying capacity.
• Carrying Capacity: The maximum population that can be supported by resources without harm to future generations or unsustainable use.
• Example: Egypt

Agricultural Density

• The number of farmers per unit of arable land.
  • Agricultural Density = (Total Number of Farmers) / (Total Arable Land Area)
• Measures how labor-intensive agriculture a country is and tells the level of economic development.
  • High (LDCs):
    • Low level of technology.
    • Farming by hand = more farmers (primary sector).
    • Low output.
  • Low (MDCs):
    • High levels of mechanization.
    • Less farmers but more output.

Population Density Affecting Society and Environment

• Population distribution and density affect political, economic, and social processes, including providing services such as medical care.
• Affects the environment and natural resources, known as carrying capacity.

ESPN Framework

• Economic: Jobs/labor/workforce, economic policies, types of economies, agriculture, industry, urbanization, markets, distribution, banking currency.
• Political: Government policies/laws, wars, conflicts, government leaders, alliances/strategies, organizations, regional/trans-regional/global structures.
• Social: Family, children, women/gender roles, ethnic groups, religion/beliefs, healthcare, science/technology, migration, social classes, freedoms/rights, demography, education.
• Environmental: Weather/climate, location, adaptation/modification, urban/suburban/rural, population distribution/density, natural resources/hazards, surroundings, attitude toward surroundings, barriers, diseases.

Consequences of Population Distribution - ESPN

• Social/Economic/Political Development:
  • Government decisions regarding public services (schools, hospitals, roads, firehouses, transportation) and infrastructure in more populated areas.
  • Rural areas = less access/quality due to lower property values, leading to less property taxes and lower-quality infrastructure.
• Economic Development:
  • High-density areas attract businesses opening stores and closing in less populated areas, driven by profit.
  • Increased job competition and opportunities.
  • Greater access to goods/services.
• Political Impact:
  • Population shift from North to South.
  • Snowbelt states lose seats in the government.
    • Texas gains seats in the House of Representatives, resulting in more say in presidential elections.
  • Changes voting patterns.
• Environmental Impact:
  • Big cities = more pollution and depletion of resources (e.g., Los Angeles, Mexico City, Delhi, Beijing).
  • Need for urban space = less wildlife habitats, farmland for food, and green spaces.
  • Carrying Capacity reached/surpassed, leading to desertification and starvation.
• Disease and Natural Disasters:
  • Higher population spreads diseases faster.
  • More deaths when natural disasters hit.
• Social Impact:
  • As population density increases, human well-being also increases due to more human interaction and innovation.
  • High density and increased cost of living lead to smaller family sizes.

Population Impact on Social Services and Infrastructure

• High population density impacts access to housing, jobs, water, and services such as sanitation, medical care, fire, police, public transportation, and waste collection.
• Easier and cheaper to provide support to clustered populations due to less distance and travel.
• Rural areas have a dispersed population but fewer facilities.
• Still extensive to provide services for large amounts of people.

Topic 3 - Population Composition

• Patterns of age structure and sex ratio vary across different regions and may be mapped/analyzed at different scales.
• Population pyramids are used to assess population growth and decline and to predict markets for goods and services.

Population Composition

• Population Composition: Makeup of population by age, sex, ethnic, racial, income, and education background.
• Age Structure: Breakdown of a population into different age groups or cohorts.
  • LDCs = younger population.
  • MDCs = older population.
  • Importance of Age Structure:
    • Helps predict future population growth and necessary next steps (building more schools or hospitals).
• Dependency Ratio: Number of dependents that each 100 working-age people (15-64) must support.
  • Youth dependency ratio and elderly dependency ratio because they have different needs.

World Dependency Categories

• High Child Dependency: High youth (
• Moderate Child Dependency: Moderate youth and low elderly; Latin America and South/Southeast/Southwest Asia; Semi-periphery/periphery.
• Double Dependency: Moderate youth and high elderly; US, France, Australia, Argentina, NZ (usually CORE).
• High Elderly Dependency: Aging population, so youth >29% & elderly <15%. Most European countries, Canada, China, Japan, SK.
  • Providing medical care/retirement homes critical (mostly Core).
• Low Overall Dependency: Influx of working-age migrants, so both youth and elderly are low; Kuwait, Qatar, UAE, Oman.
  • Social burden slightly overestimated because many work past 65.
• Higher dependency = more people working age has to support; burden.

Population Pyramids

• Population pyramid: Useful for comparing age and sex structure.
  • Speaks of a country’s past-effects of past on the pop.; war, medical advancements, BUT also its future → what tax payer $ go towards.
• Four typical shapes:
  • Rapid growth
  • Slow growth
  • Stability
  • Decline
• Can be used at various scales -Ex: Country or City level.

Types of Population Pyramids

• Rapid Growth:
  * Characteristics:
  * Wide base-rapid pop. growth
  * Narrow top-low life expectancy
  * LDC’s/Periphery
  * Challenges:
  * Struggle w/ edu. and creating jobs
  * Example:
  * Tanzania
  * Nigeria
  * Sub-Saharan Africa
  * Periphery
• Slow Growth:
  * Characteristics:
  * Birth rates slow down (just over death rate)
  * Somewhat narrow base; more cylindrical or slightly pyramid
  * Pop. slowed by:
  * Neg.: economic crisis, epidemic, or policies OR
  * Pos.: incr eco adv., access to edu., & contraceptives
  * Example:
  * China-1 child policy
  * India
  * Semi-Periph.
• Stability:
  * Characteristics:
  * Birth rate and death rate are similar → pop growth is essentially 0 (ZPG)
  * Even cohorts-cylindrical (around replacement level: 2.1)
  * Challenges:
  * Pop. will decline unless policies are put into place to ↑ CBR or continue to have enough immigrants
  * Example:
  * US
  * Canada
  * Mainly Core
• Decline:
  * Characteristics:
  * Narrow base, top heavy for older pop.
  * Low birth rate and negative pop. growth
  * Challenges:
  * Labor shortage & lower demand for consumer goods bc fixed income
  * Example:
  * Japan
  * Germany
  * Eastern Europe
  * Spain
  * Italy
  * CORE

Factors shaping Population Pyramids

• Events
• Policies
• Trends
• Drastic Events: the aftermath of WWII on Germany and Russia
• Government Policies: China's one-child policy or the college campus
• Areas having big college age cohorts: Oman, UAE, Qatar, and Saudi Arabia have had mass influx of male immigrants for labor increasing the male side of the pyramid

Topic 4: Population Growth and Decline

• Fertility, mortality, and migration determine populations growth and decline.
• Social, cultural, political, and economic factors influence the above.
• Geographers use the rate of natural increase & population-doubling time to explain population growth & decline.

How Has the Population Grown?

• Demographic equation: Method for calculating total pop. of a country/place based on natural increase and migration over time.
  Population at beginning + Total Births + Total In-migrants - Total Deaths - Total Out-migrants = Population at end
• Starting around 1750-mid 1800’s
  • Agricultural Revolution: 1st cause of pop SPIKE
  • Industrial Revolution
  • Rapid urbanization
  • Advances in healthcare & sanitation
  • Pop. in LDC’s will continue to grow the most because high birth rates (sub-saharan Africa, S/SE Asia)

Factors that determine a population’s growth & decline

1. Fertility
   • Crude Birth Rate (CBR)
   • Total Fertility Rate (TFR)
2. Mortality
   • Life Expectancy
   • Crude Death Rate (CDR)
   • Infant Mortality Rate (IMR)
3. Migration

Crude Birth Rate (CBR)

• Crude birth rate: The avg. # of births per 1000 people
  CBR = (Births per Year / Total Population) * 1000
• Crude bc it does not consider the pop's age or sex
• Can vary a lot by country due to:
  • Age-sex comp. (more young women = higher CBR)
  • Economic dev.
  • Social norms for family size.
  • Low Birth Rate: CBR is bwn 10 & 20 births per 1,000 people (MDC’s-N. America, Europe) CORE
  • Transitional Birth Rate: CBR is btwn 20 & 30 per 1,000 people (LA, Central & SE Asia) SEMI-PERIPH./Periph
  • High Birth Rate: CBR more than 30 per 1,000 people (LDC’s-sub-Saharan Africa)

Total Fertility Rate (TFR)

• Total Fertility Rate: The avg # of children born per woman during her reproductive lifetime (15-49 years of age)
• More accurate than CBR
  • Focuses on female segment of pop.
  • Reveals avg. family size/cultural norms
  • Suggests future changes in the pop. structure
• Better for showing regional/national comparisons.
• High TFR = LDC
• Low TFR = MDC
• Replacement level fertility: Avg. # of children needed to replace both parents & stabilize pop. over time.
  • TFR of 2.1; anything less will lead to pop. decline

Factors Affecting Fertility Rates

• Economic development
  • LDC’s- primary sector (agri.), ↑ child mortality & need more for work/income, also lack contraceptives
  • MDC’s- career focused & cost more to raise kids here
• Religious and Cultural Influences
  • Islam & Catholicism ban birth control but NOT ALWAYS the case (Italy and Spain TFR 1.3- Catholic)
• Education
  • Women w/ ↑ edu. = ↓ TFR; working in formal sector
• Gender Roles
  • Culturally specific notions of what it means to be a man or woman →
  • more babies = more feminine Traditional role for women → less edu./ less present in the formal sector → ↑ TFR
• Population Policies
  • China’s gov. led birth control policies (TFR 1.8); others offer incentives to boost fertility rates

Crude Death Rate/Mortality Rate (CDR)

• Crude death rate: The # of deaths per year per 1000 people; (total # of deaths / total mid year population) x 1000
  • “Crude” because doesn’t distinguish btwn old & young
  • Can vary based on age-sex structure AND economic dev. level
  • Sub-saharan Africa = high CDR because of economic difficulties, disease, war, lack sanitation, & lack of healthcare
  • Or-Indig. in Americas wiped out from diseases brought by Euro.
  • MDC’s = high CDR sometimes bc higher elderly pop. - higher living standards & access to healthcare → people live longer, but a high elderly rate creates a high CDR over time

Infant Mortality Rate (IMR)

• Infant mortality rate: measure of how many infants die within the first year of their life per 1000 live births; best indicator of living standards
• Affected by:
  • Health-better access to clean water
  • Nutrition/ better food production
  • Sanitation-sewer system
  • Education
  • Housing
  • Access to medical care (vaccines, antibiotics, prenatal care)
• Used to be 200 per 1000 but improved to average IMR of 31
• MDC’s = Lower Infant Mortality Rate
• LDC’s = Higher Infant Mortality Rate

Rate of Natural Increase (RNI)

• Rate of natural increase (RNI): The diff. btwn the # of births and deaths in a given year, when expressed as a % of total pop. RNI = ((CBR - CDR) / 10)
• CBR changes more than CDR so a different RNI is because of CBR
• RNI is negative when a country has more deaths than births (E. Europe, Japan)
• RNI does NOT take into consideration immigration; a country can have a negative RNI but not be decreased in pop
• LDC’s tend to have high RNI
• MDC’s tend to have low RNI (due to low total fertility rates)

Zero Population Growth (ZPG)

• Zero pop. growth (ZPG): when a country has the same # of births & deaths in a given year, its RNI is zero; if the TFR remains 2.1 consistently
• May try to achieve this to reduce pop but changing age-sex structure/cohorts will still have economic impacts
  • Ex: China- aging pop. & shortage of labor and slowing economy
  • Doubling time: the # of years it takes for a pop to double in size
    • Calculated by:
      • The rule of 70: calculating the doubling time by dividing 70 by the country’s rate of natural increase (RNI)
        Doubling Time = 70 / RNI
      • This does not account for immigration either
    • LDC’s = smaller doubling time because of high CBR
    • MDC’s = LARGE doubling time bc little if any pop incr.

Topic 5 & 6 - Demographic Transition Model

• The Demographic Transition Model (DTM) can be used to explain population change over time.
• The epidemiological transition model explains causes of changing death rates.

Demographic Transition Model (DTM)

• Conceptualizes how crude birth rates & crude death rates as well as the resulting rate of natural incr. change overtime as countries go through industrialization & urbanization
• Shows levels of social & eco. dev.
• 5 stages in the transition process:
  1. High stationary stage
  2. Early expanding stage
  3. Late expanding stage
  4. Low stationary stage
  5. Natural decrease

Stage 1

• High CBR
  • Reasons: Children not likely to survive long-term => High IMR
  • Need for child labor in agricultural societies
• High CDR
  • Short life expectancy due to famine, poor diet, inadequate housing, disease, warfare, poor sanitation
• Natural Increase Rate: 0 to 0.5%
• Economy & Society: Subsistence agri (for survival)/ hunter gathering
• Examples: NO COUNTRIES in this stage BUT some isolated groups
• Population Composition: Youth dependency-few elderly bc poor healthcare/living conditions

Stage 2

• High CBR
  • Reasons: Still need big fam. for agri. labor
• Rapidly Decreasing CDR
• Reasons: Still short life expectancy, BUT Improved nutrition/food surplus, sanitation, and medicines
• Natural Increase Rate: 0.5% to 4% -MOST GROWTH HERE
• Economy & Society: Shifting to commercial agri-for $, rural - urban migr for secondary sector jobs in city, emigration to Core for better job opps
• Examples: PERIPHERY-LDCs: Sub-Saharan Africa, Afghanistan, SE Asia, Pakistan
• Population Composition: Youth dependency

Stage 3

• Declining CBR
• Reasons: Urbanization decr need for child labor - smaller living spaces & kids cost $; Incr. in healthcare & women status→female edu→ contraceptives → formal sector jobs → ↓ TFR
• Slower Declining CDR
  • Life expectancy incr. due to more medical adv → lower IMR → don’t need to have as many babies
• Natural Increase Rate: 4% to 0.8%-Growth SLOWS
• Economy & Society: Rural to urban migr. as Secondary sector grows as well as some Tertiary → less int’l migr.
• Examples: SEMI-PERIPHERY: India, Mexico, Brazil, Turkey, Indonesia
• Population Composition: Moderate Dependency

Stage 4

• LOW CBR
  * (TFR around replacement level-2.1): Same as previous Incr.
  * healthcare & women’s status → less kids → incr. cost of living (daycare & edu) bc in Core
• Low & stable CDR life expectancy continues to ↑
  * from medical adv & higher income for better healthcare & nutritious food
• Natural Increase Rate: .8% to 0%-Falls and then stabilizes to ZPG
• Economy & Society: Urbanized-Large Tertiary sector; ↓ GII, ↑ GEM, ↑ HDI, ↑ GDP
• Examples: Majority of MDCs- China, Australia, Canada, US, France, UK
• Population Composition: Double dependency starting to shift to elderly dependency: Very low Stable or decreasing:

Stage 5

• CBR BELOW CDR: At replacement level: (TFR: 2.1) / ZPG or BELOW: same as previous-↑ woman status → formal sector Jobs → ↑ cost of living → ↓ TFR
• LOW CDR Most medically advanced (sometimes CDR will incr bc SO MANY elderly→ more die at the older ages that incr CDR)
• Negative to Very-Low Natural-Increase Rate: !%
• Economy & Society: Urbanized –large tertiary sector May create pro natalist policies OR welcome immigrants
• Examples: Japan, Germany, S. Korea, Singapore, most of Eastern Europe Population Compositionhigh ELDERLY dependency ratio
• Population Impact: High elderly Dependency Ratio:

Critiques of the Model

• Nonlinear progression
  • Model portrays linear progression but countries can back track: EX: Angola and Afghanistan countries has had the highest world death rates to a conflict!
  • Wealth doesn’t always mean decreased in fertility rates (there are always exceptions to the rule)!EX: Oman country with oil and high birth rates
  • Countries with war and uncontrolled disease don’t necessarily follow the model and it Places restrictions/limitations on migration
  • There isn’t to much opinions of migrating for stage two and three that you did to release pop-pressure
• Accelerated Transition progression can be so rapid it skips a stage