Human Population Flashcards
___ is the most populated country in the world, representing 1/5 of the global population.
China
What were some environmental side effects of China’s growing population and industrialization?
soil erosion, decreased water resources and air pollution
1970 population control program in China
a system that kept most families from having more than one child with a goal of correcting overpopulation; applied more often to urban areas as children were seen as beneficial for help in rural contexts; encouraged later marriages and increased access to contraceptives and abortion; rewarded abiding families with government jobs + better housing + medical care + school access while other families experienced monetary fines, employment discrimination and social scorn
What were the unintended consequences of China’s population control program?
shrank the labor force (increased the proportion of older people compared to younger people) which raised labor prices and led to companies seeking cheaper labor elsewhere; older people were left without support as a large burden was placed onto single children to provide for their aging parents; resulted in too few women as men carried the family name and usually helped on farms + cared for their parents while women usually got married and left their homes (the limit encouraged some to use selective abortion); caused men to leave their towns as migrant workers without an “anchor” + engage in more risky sexual activity
How was the one-child policy in China altered over time?
it was loosened on occasion to allow certain people to apply for an exemption (e.g., if either parent was an only child), although few did apply; 2015 was changed to a 2-child policy
What have been some concerns/criticisms regarding China’s population control program?
alterations to the policy could be ineffective as parents became used to material wealth and an urban lifestyle and may not want the extra cost of another child based on surveys (though birth rates increased); some view it as an intrusion into reproductive choices (though it was effective)
What country is quickly rising in population and may overtake China as the country with the largest population?
India
What happened with India’s population control policies in the 1970s?
included forced sterilization which led to public outcry and was changed; now less coercive, involving family planning and reproductive healthcare (less stringent than China’s)
Nearly all of the world’s population growth has occurred in the last ___ years.
200
Why has so much of the world’s population growth occurred in recent time?
because it is exponential - even with a steady rate, more people in each new generation = greater increments of increase; contributing causes include better technology, sanitation, medical care and agricultural output (make death rates lower)
When did the global population growth rate peak?
1960s (2.1%)
When did the population growth rate peak in the most and least developed places?
1950s; 1990s
Carrying capacity
the maximum population size that the environment can support; very different estimates from many different sources for that which corresponds to humans
Thomas Malthus on carrying capacity
said war, disease, and famine would decrease the population; did not occur + agriculture increased food supply during and after the 19th century
Paul Ehrlich on carrying capacity
said growth would exceed food supply and famine/conflict in the late 20th century would decrease the population; did not occur + Green Revolution increased food supply in developing regions
Cornucopian view (economics)
states there is no problem with continued population growth if new resources are found or created to replace those that are depleted (but not all resources can be replaced)
IPAT model
a variation on Paul Ehrlich and John Holdren’s 1974 formula; provides a way to think of the effect of population growth and other factors on environmental quality; I = P * A * T, where I = total impact from population (P), affluence (A) and technology (T); sometimes extra variable for sensitivity to human pressures (S) is added (or other factors like education, laws, ethical standards, social stability, etc.)
How do the IPAT variables affect environmental quality?
increased population = more space used, more resources used, more waste; increased affluence = more per capita resource use; increased technology = a greater ability to exploit resources but also decreased impact and resource strain (with efficiency, renewable energy and lower emissions); increased sensitivity = more impact from each additional person in certain regions
Demography
the application of principles from population ecology to the study of statistical change in human populations; covers population size, density, distribution, age structure, sex ratio, and rates of birth + death + immigration + emigration (same as population ecology for other organisms); helps predict population dynamics and environmental impact
___ of the total human population lives in one of the top 10 most populated nations.
3/5 (represents clumped distribution)
Where is human population density the highest and lowest on a global scale?
temperate, subtropical, and tropical climates, especially along coasts and rivers; extreme-climate biomes such as deserts, rainforests and tundra
Where is human population density the highest on a local scale?
in towns and cities
Why can areas with low population density still be greatly affected environmentally?
they have higher sensitivity (e.g., deserts or arid grasslands are easily degraded by agriculture and ranching that use a lot of water)
Age structure
the relative numbers of individuals of each age class in a population, used to predict future dynamics; if most are past reproductive age the population is expected to decline while if most are at or younger than reproductive age the population is expected to increase (relatively even = stability)
