Chapter 4

Renewable Resources

• a resource that can be renewed as quickly as it is used up and can, in theory, last indefinitely.

Nonrenewable resources

• any natural resource from the Earth that exists in limited supply and cannot be replaced if it is used up; also, any natural resource that cannot be replenished by natural means at the same rates that it is consumed

Fossil fuel

• any combustible organic material, as oil, coal, or natural gas, derived from the remains of former life.

Ore

• a metal-bearing mineral or rock, or a native metal, that can be mined at a profit.

Hydroelectric power

• a form of energy generated by the conversion of free-falling water to electricity; the generation of electricity by using the motive power of water; also called hydroelectricity

Geothermal energy

• a form of energy obtained from within the earth, originating in its core; also, energy produced by extracting the earth's internal heat

Conservation

• the act of conserving; prevention of injury, decay, waste, or loss; preservation:

Compost

• a mixture of various decaying organic substances, as dead leaves or manure, used for fertilizing soil.

Recycling

• to treat or process (used or waste materials) so as to make suitable for reuse: