Chapter 10 Water Resources and Water Pollution

Earth's supply of fresh water _______.

• mainly exists in liquid form

• includes surface water and groundwater

• is distributed evenly across Earth's land areas

• is about half its supply of saltwater

Most of earth's fresh water is stored _____.

• in the ocean

• in the ground

• in caves

• in rocks

Two-thirds of annual surface runoff is _____.

• available for human use

• lost in seasonal floods

• identified as reliable surface runoff

• supplied by melting ice and snow

• used for watering crops

Which of the following is NOT a benefit provided by dams and reservoirs?

• transfer of water

• storage of surface runoff

• generation of electricity

• disrupts ecosystems; displace people

Which outcome would you expect when water is removed from an aquifer faster than it is replaced on a regular basis?

• the water cycle stops

• subsidence of land above the aquifer

• pollution of water within the aquifer

• reduced fish populations within the aquifer

Which statement about using freshwater irrigation is correct?

• flood irrigation is very efficient

• Most of the world's irrigation water reaches crops

• Most irrigation systems are very inefficient

• Drip irrigation is the least efficient irrigation system.

Improving irrigation practices would ______.

• increases the amount of water loss

• achieves the largest reduction in water loss

• disrupts ecosystem servies

Which activity represents the single largest home use of water in the United States?

• dishwashers

• lawn sprinkling

• showers and baths

• toilet flushing

One reason why contaminated groundwater is very difficult to clean up is that _____.

• it exits too deep underground

• it has very low levels of dissolved oxygen and it cannot cleanse itself

• populated with too many rocks

Water used from shower, sinkes, dishwashers and clothes washers is defined as:

• groundwater

• surface water

• gray water

• runoff