Chap 12: Freshwater Distribution, Use, and Sources. Flashcards
Exam 2 Prep
How much of the planet’s water is saltwater? (Hint: it is the majority).
97.5%
How much of the planet’s water is fresh? (Hint: it is the minority).
2.5%
Where is most of the freshwater stored?
80% is in glaciers and polar regions.
20% of fresh water is stored in a _ _ _ _ _ _ s
Aquifers.
Where is the minority of freshwater?
On the surface in rivers and ponds.
Is freshwater evenly distributed across the planet?
No.
True or false: many areas with high populations have significant stores of freshwater.
False.
What is freshwater mostly used for?
Agriculture at 70%.
What is the second highest use for freshwater?
Industrial at 20%.
What is the third type of use for freshwater?
Domestic at 10%.
True or false: developing nations hardly use water for agriculture.
False, agriculture is their highest use for freshwater.
True or false: industrialized nations can afford to conserve freshwater use, particularly in agriculture.
True.
What are consumptive uses of water?
They do not return water to its original source after use. Examples include agricultural irrigation and residential use.
What are non-consumptive uses of water?
Water is immediately returned to the original source after use. Examples include hydroelectric dams and industrial cooling towers.
What is groundwater?
Water that is stored underground in aquifers.
How does water end up in aquifers?
Water enters the soil from a recharge area and ends up in an aquifer.
What ecosystem service does the soil provide when it allows water into an aquifer?
Filtration.
What is overdraft?
When water is taken from aquifers faster than rainfall can recharge the supply. This causes water levels to drop.
How does overdraft lead to sinkholes?
If too much water is removed, then the ground becomes unstable and sinks in.
Surface water is easily accessible to humans. Why can this be bad?
It is also easier to contaminate.
