Unit 2: Population and Migration Patterns and Processes
Key Concepts:
Basic Population Statistics
- Population growth involves two main concepts: the rate of natural increase (RNI) and the demographic equation.
- The demographic equation uses uses birth rates, death rates, immigration, and emigration statistics to show population growth
- Birth rate, also known as natality, is the crude birth rate (CBR) and an annual statistic
- High birth rates: rural agricultural Third-World countries
- Low birth rates: urbanized industrial and service-based economies
- Ex: total number of infants born living is counted for one calendar year and then calculated
- CBR: Number of Live Births/Total Population x 1,000
- Death rate, also known as the mortality rate, is the crude death rate (CDR) and an annual statistic calculated in the same way as the birth rate.
- High death rates: a country that is experiencing war, disease, or famine, such as poor Third-World countries experiencing poverty, poor nutrition, epidemic disease, and a lack of medical care.
- Green Revolution: (increased food and nutrition) and access to sanitation, education, and health care
- CDR: Number of Deaths/Total Population x 1,000
- The rate of natural increase (RNI), or the natural increase rate (NIR) is the annual percentage of population growth of that country for that one-year period.
- RNI: Birth Rate - Death Rate/10%
- Negative RNI means the population has shrunk
- Happens in in highly urbanized First-World countries and where the traditional roles of women in the country of mother and housewife have deteriorated significantly
- Reduced fecundity: when the majority of women are heavily engaged in business, they are far less likely to have children
- Double-income no-kid (DINK) households and single-parent–single-child homes are far more common; higher rates of divorce
- Natural increase does not account for immigration or emigration
- Ex: a country with a high rate of natural increase can have an unexpectedly low long-term population prediction if there is a large amount of emigration
- Doubling Time: how long it would take for a country to double in size
- Formula: 70Rate of Natural Increase
- To estimate the RNI for each year in the future by examining a country’s position: (Pop. × RNI1) + (Pop. × RNI2) + (Pop. × RNI3) + (Pop. × RNIn) = Future Population
- Net Migration Rate (NMR): the number of immigrants minus the number of emigrants for every thousand members of the population; can be negative
- Formula: Number of Immigrants - Number of Emigrants/Population /1,000
- Population Growth Percentage Rate = (Birth Rate - Death Rate) + Net Migration Rate/10%
- Total fertility rate (TFR) is the estimated average number of children born to each female of birthing age (15 to 45)
- Formula: Number of Children Born/Women Aged 15 to 45
- Replacement rate is a TFR of 2.1
- A large population must have 2.1 children per female of birthing age.
- Dependency ratio provides the number of people too young or too old to work compared to the number of people in the work force
MODELS
- The demographic transition model (DTM) is a theory of how population changes over time and provides insights into issues of migration, fertility, economic development, industrialization, urbanization, labor, politics, and the role of women.
- Newly industrialized countries (NICs) can also be placed on the model, but you have to change the dates as to when they reach the significant turning points in their history
- The epidemiological transition model (ETM) specifically accounts for development due to the increasing population growth rates caused by medical advances
- The phase of development is directly followed by a stabilization of population growth as the procreation rates decline
- Can predict how its population will change over time and speculate as to how much it can grow in size
- Ex: we can estimate a population projection that the planet’s population has reached only about two-thirds of its potential
- The S-Curve of Population
- Ex: an animal population that receives a vast amount of food or removes predators from their habitat will result rapid population growth followed by a plateau or decline due to a population reaching or exceeding the area’s carrying capacity
Stage-By-Stage
- Stage One:
- Historically characterized by pre-agricultural societies engaged in subsistence farming and transhumance
- Birth rates and death rates fluctuate due to climate, warfare, disease, and ecological factors, but overall, both rates are high
- Child mortality and infant mortality were very high
- Result: little population growth until the later part of stage one when death rates begin to decline; RNI is generally low or negative
- Present-day Third-World countries engaged in long periods of warfare have late stage one characteristics
- Stage Two:
- Typically agriculturally based economies
- Birth rates remain high and life expectancy rises while death rates decline over time; RNI increases
- Infant and child mortality is still an issue due to a lack of medical care and
- Poor nutrition for expectant mothers and infants
- The vast majority of populations in stage two countries live in rural regions as a result of agriculture’s economic prominence
- Stage Two 1/2:
- NIC countries are characterized by economies that focus on manufacturing as the primary form of economic production and employment
- Birth and death rates decline
- Rapid population growth; high RNIs; rapidly increasing rate of urbanization
- Migrants responding to the pull factor of employment opportunity rapidly fill the cities
- Stage Three:
- Historically where most “industrialized” or manufacturing-based countries were found in the transition
- Shifted their economies to a more service-based focus
- Birth and death rates decline due to urbanization
- The diffusion of fertility control due to access to health care and the availability of contraceptives as well as reducing the diffusion of disease due to medical advances
- Stage Four and Five
- Birth and death rates converge to result in limited population growth and population decline
- Service industries like finance, insurance, real estate, health care, and communications that drive the economy; manufacturing is dying
- Ex: in the United States, services are 80 percent of the gross domestic product (GDP) and manufacturing is only 20 percent
- Both the final stages of the DTM and ETM occur when birth rates bottom out into the lower teens
- Zero population growth (ZPG) (RNI of 0.0 percent): birth rates reach the same level as death rates
- Elderly population means fewer people investing their money:
- Causing less money to circulate through the society, which results in stagnation
- Lower tax base to support the rest of the nation
- Shortage of labor supply
- Countries that are near or below zero population growth levels offer incentives to citizens to have more children.
- With so few children being born, fewer people enter the workforce over time
- Become dependent upon foreign guest workers
- Many former Communist countries of Eastern Europe have stage four demographic characteristics
- Economic restructuring has brought economic, political, and social hardship to many communities
- Malthusian Theory states that the global population would one day expand to the point where it could not produce enough food to feed everyone.
- Malthus saw was that food production did grow over time but in a slow arithmetic manner, while human population grows exponentially
- As new food products and methods were adopted, another large volume of food would be added to global production and supply
- This meant that food production has continued to stay ahead of population growth.
- The science of genetics did not make any impact on global food production until the 1950s
- Neo-Malthusians warn that a Malthusian catastrophe could still occur.
- Sustainability. If too many of the world’s current growing areas are damaged, can food production keep up with the increased demand?
- Increasing Per Capita Demand. Can the planet provide enough food when all 10 billion of us eat like the First World does today?
- Natural Resource Depletion**.** Can a world with 10 billion people have enough material to house everyone, enough fuel to heat all the houses, and enough food to feed everyone?
Population Pyramids
- Graphical way to visualize the population structure of a country or place as well as the gender and age distribution of the population
General Principles:
- Males are always on the left of the pyramid and females are on the right
- Each bar is an age cohort, generally made up of five-year sets
- The origin (0-value) of each bar graph is the center and increases in value as you move left or right outward from the center
- A gap in data for both males and females is likely a sign of past war inside that country, epidemic disease, or famine.
- The general shape of the pyramid is reveals the character of the country, state, province, or city that is being diagrammed.
- increased mortality from disease and old age causes significant declines in the elder population, causing the top to shrink
- Population density is calculated in two main ways.
- Arithmetic density is the number of people per square unit of land
- Physiologic density is the number of people per square unit of farmland
- Important in understanding the geography of countries where the amount of arable land is limited
- The population center of a country is found by averaging the spatial weight of population across the country.
- Overpopulation is a major concern both in resource-poor regions and across the globe.
- Nonrenewable energy sources will be depleted if conservation efforts and population control methods are not mandated by governments
- Alleviating concerns over decreasing amounts of personal space
Migration
- Migrants are generally those who voluntarily move from location to location.
- Many countries experience internal migrations that significantly change the countries’ population distributions.
- Interregional, or internal, migrants: those who move from one region of the country to another
- Transnational migration: occurs when migrants move from one country to another.
- Forced migration: people may be taken or coerced from their homes for forced labor through human trafficking or enslavement
- Undocumented immigrants: people who come seeking refuge or employment opportunities but do not have government authorization
- Amnesty programs: allow undocumented immigrants the opportunity to apply for official status or citizenship without facing arrest or deportation
- Step migration: occurs when people move up in a hierarchy of locations, with each move to a more advantageous or economically prosperous place
- Chain migration: occurs when a pioneering individual or group settles in a new place, establishing a new migrant foothold.
- Life-course changes: when people move because of major changes in the course of their lives.
Push and Pull Factors
- Push factors are specific things about the rural agricultural landscape and livelihood that force people off the farm
- (ex: armed conflict, environmental pollution, increased land costs)
- Pull factors are specific things about cities that draw people to the urban landscape
- (ex: job opportunities, medical care, education, service access, entertainment)