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Enviro. 7
Question | Answer |
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Human Population Growth - driving factors | Changes in population size Fertility Life expectancy Age structure Migration |
Crude birth rate | the number of births per 1000 individuals per year. |
Crude Death Rate | the number of deaths per 1000 individuals per year. |
Global population growth rate | [CBR – CDR] ÷ 10 = percent growth rate [20 – 8 ] ÷ 10 = 1.2% ---> So, what is the population growth rate for a nation? |
Doubling time | the number of years it takes a population to double. The rule of 70 may be used to approximately calculate the doubling time in years. |
Total fertility rate | an estimate of the average number of children that each woman in a population will bear. |
Replacement level fertility | the total fertility rate required to offset the average number of deaths in a population and for the current population size to remain stable. |
Developed countries | countries with relatively high levels of industrialization and income. TFR is typically 2.1. |
Life expectancy | the average number of years that an infant born in a particular year in a particular country can be expected to live, given the current average life span and death rate of that country. |
Net migration rate | the difference between immigration and emigration in a given year per 1000 people in a country. This difference, divided by 10, is the percent net migration rate. It may be positive (net immigration) or negative (net emigration). |
Demographic transition | suggests that as a country moves from a subsistence economy to industrialization and increased affluence, it undergoes a predictable shift in population growth. |
Phase one of demographic transition | Slow population growth because there are high birth rates and high death rates that offset each other. |
Phase two of demographic transition | Rapid population growth because birth rates remain high but death rates decline due to better sanitation, clean drinking water, increased access to food and goods, and access to health care. |
Phase three of demographic transition | Stable population growth as the economy and educational system improve and people have fewer children. |
Phase four of demographic transition | Declining population growth because the relatively high level of affluence and economic development encourage women to delay having children. |
Urban populations | have grown, and while they represent one-half of the world’s population, they consume three-fourths of the resources. |
Gross Domestic Product (GDP) | the value of all products and services produced in a year in that country. GDP is made up of consumer spending, investments, government spending, and exports minus imports. A countries GDP often correlates with its pollution levels. |
IPAT Equation | To estimate the impact of human lifestyles on Earth we can use the IPAT equation: Impact = Population x Affluence x Technology |