Human Population Flashcards
Define Population distribution
The pattern where people live on Earth
Define Population density
Average number of people living in a square kilometre (used to estimate whether an area is sparsely or densely populated)
Define sparsely/densely populated
An area where many/fewer people live
How does an area become overpopulated
When it’s population density exceeds the carrying capacity of the environment
Define carrying capacity
Maximum population size that can be supported by the resources available in a a particular environment
Define quality of life
The standard of happiness, health and comfort
Physical factors that influence the distribution & density of population
- Climate (temperate areas> extreme weather patterns)
- Relief (flat land> steep: for settling, building, farming)
- Soils (fertile>infertile: farming)
- Natural resources (minerals, forests: to boost economic activity)
- Accessibility (river valleys/coastal locations> remote/inaccessible)
- Vegetation (open grasslands> dense/dangerous swamps/forests)
Human factors that influence the distribution & density of population
- Political (stable/democratic>politically volatile)
- Economic (high income: better living standards&job opportunities)
- Communications (good transport networks & trading links)
- Social (migration policies, industrial expansion)
Why are mountain areas less attractive?
Extreme climates (heavy precipitation)
Steep slopes
Shallow & acidic soils
Dense forests & little flat land
Constructing transport/settlements is expensive
Few job oppportunities
Few industries locate here
Farming is hard
Why are coastal plain areas more attractve?
Flat land
Milder climate
Regular rainfall
Most of the farming industry is located here
Gentler relief (easy to construct roads, railways)
Excellent communications = more industries= more jobs)
High rise buildings to maximise use of the minimal land
Define the growth curve of populations
A theory that attempts to describe and explain how and why the number of living things in a given area or habitat changes over time
Ecological theory based on how organisms such as bacteria behave in the animal kingdom
Explain the growth curve of populations
Based on the assumption that limited resources will always control the growth and continued existence of living things
Sigmoid/ ’S’ shaped graph curve
Phases of the Sigmoid
Lag phase
Log phase
S-phase
Stable phase
Decline phase
What is Lag phase?
Growth is slow since organisms have to adjust to the environment
What is Log phase?
Exponential growth as the number increases because available resources (food/water) are unlimited
What is S-phase ?
Slows down because the resources become restricted/finite
What is Stable phase?
Carrying capacity has been reached- stable population)
What is Decline phase?
Population exceeds carrying capacity leading to overpopulation
May be triggered by a change meaning environemnt can no longer support the population (eg drought)
Why can’t this be applicable to humans ?
Doesn’t take into account human intelligence and ingenuity or human emotion and solidarity (donations during disasters)
Define death rate
The average number of deaths in the world per 1000 population
Define birth rate
The average number of births in the world per 1000 population
How have humans increased the carrying capacity ?
Developing intensive agriculture (domestication of animals and wild grains)
Creating sophisticated irrigation schemes
Combat diseases through medical care, antibodies,surgical procedures, improved sanitation
How do governments manage a high birth rate?
Anti-natalist policies
Improved healthcare and educations
Free family planning services
Sex and reproductive health programmes in school
Promotional literature/ advertising
Raise education levels of girls (increases average age of marriage)
Forced sterilisation/ One Child policy (extreme)
How do governments manage a low birth rate?
Free pre and post natal care
Subsidised day care nurseries to reduce cost of child care
Generous tax allowances until the child is 18
Improved pensions and child benefit allowances
Full pay maternity leave
Prioirity to families for state housing (100% mortgages)
Define migration
Movement of people from one place to another (immigration & emigration)
Effects of overpopulation
Environmental degradation
Depletion of natural resources
Mass poverty
Political instability
Population pyramids of MEDCS
Narrow base (low birthrate)
Low proportion of yound dependants
Straight sides up (death rate is low)
Tall, wide top (high life expectancy)
Population pyramids of LEDCS
Wide base (high birth rate& many children being born)
Large proportion of young dependants (high birth rate)
Even decline in shape up (high death rate)
Narrow, short top (low life expectancy)
Why is a low dependancy ratio good?
Burden of tax and funding public services is spread
High dependancy ratio may lead to higher taxes and a cut on the expenditure on public services in order to meet costs
Define dependency ratio
Ratio between those of the working age(economically active) who are paying taxes and those of the non-working age (the dependants), who rely on the taxes to support them
Define population structure
Composition or make up of the people living in a place likea town or city, or in a larger area such as a country or continent
Population pyramid
Used to show the gender and age structure of a population
0-14 (young dependants- not employed)
15-64 (‘economically active’)
65+ (older dependants- mostly retired)
Population change formula
Birth rate- death rate +- net migration
Define net migration
Difference between immigrants and emigrants
Define natural increase
The rise/fall calculated by subtracting the death rate from the birth rate
Changes in population due to-
Birth rate
Death rate
Migration
Define Age-sex structure
The number or proportion of males and females in each age category
Define sex ratio
Proportion of males to females
Influences on death rate
Availability of clean drinking water
Standard/availability of medical facilities & health care
Diets amongst children/ young women
Quality of sanitation
Presence of infectious diseases
Social/ political issues
Age-sex structure/sex ration (older people)
Living standards
Define Infant mortality
The number of deaths of children aged less than 1 year per 1000 live births
Factors determining the level of birth rate
Infant mortality
Life expectancy
Define Life expectancy
The average number of years that a person is expected to live
Influences on infant morality/ birth rate
Age-sex structure/ sex ratio
Quality of childbirth and post natal health care
Availability of family planning services and contraception
Level of education/ female literacy rates
Average age women marry
Influenceof religions and social customs
Effect of government policies to boost/reduce population growth
Economic influences- rising costs in MEDCS (lowers)/poverty in LEDCS (raises)
