Population And Resources Flashcards
Define carrying capacity.
The number of people who can be adequately supported by the productive capacity of the land
Define demographic transition.
Historical shift of birth and death rates from high to low levels in a population
What is the high fluctuating stage (1) of the demographic transition model?
Stable, high birth rate and fluctuating high death rate; slow population growth; pre-industry (Amazonia)
What is the early expanding stage (2) of the demographic transition model?
Improved healthcare; fewer deaths; high birth rate; peak population growth; better life expectancy and lower child mortality (Bangladesh, Bolivia)
What is the late expanding stage (3) of the demographic transition model?
Social norms change and birth rate decreases (Brazil, India)
What is the low fluctuating stage (4) of the demographic transition model?
Low birth and death rates; slow population growth (UK, South Korea)
What is the natural decrease stage (5) of the demographic transition model?
Birth rate falls below death rate; declining population (Germany, Japan)
Define resource.
Any aspect of the environment which can be used to meet human needs
The western states of the USA cover 60% of the country’s land area but only have ……..% of the population and …….% of the mean precipitation.
40, 25
In the past what was the solution to the water issues in western USA?
Aqueducts taking water from areas of water surplus to shortage
In California how much of the state’s runoff originates in the northern third?
70%
How much of the demand for water in California is in the southern two thirds of the state?
80%
What are the main two reasons for water demand in California?
Irrigation and sprawling urban areas
How much of the state’s water is used for agriculture?
Over 80% despite accounting for less than 10% of the economy
Which states does the Colorado River flow through?
Colorado, Utah and Arizona; it then follows the Arizona-Nevada and Arizona-California borders before entering Mexico
What construction marked the beginning of artificial control of the Colorado?
The Hoover Dam
The Colorado River Compact promised …….. of water to be split between the Upper Basin, Lower Basin and Mexico.
20.35 trillion litres
What is the average annual discharge of the Ricer Colorado since 1930?
17.25 trillion litres
How many people does the Colorado sustain?
25 million
Why did Arizona need the Central Arizona Project?
Arizona was taking much less than its legal entitlement of water from the Colorado as it could not afford a water transfer system, however it was overdrawing from aquifer supplies and needed to support the cities of Phoenix and Tucson
What is the impact of CAP?
California now has to learn to live with their original entitlement of water from the Colorado when they have been taking more
How much of the Colorado’s water is lost through leakage and evaporation?
25%
Where could water be recycled to improve efficiency?
In industry and sewage
More efficient forms of irrigation (compared to open-ditch systems) include…
…sprinkler systems which are 10 times more efficient or drip irrigation which is 100 times more efficient