Ch 4 Sec 3

Question 1

humus

Answer 1

Bacteria, insects, and worms break down the plant and animal material

Question 2

leaching

Answer 2

Downward movement of minerals and humus in soils

Question 3

contour plowing

Answer 3

works across a hill, rather than up and down

Question 4

soil exhaustion

Answer 4

Soil becomes nearly useless for farming

Question 5

Crop rotation

Answer 5

Planting different crops in alternating years

Question 6

Irrigation

Answer 6

Water that is artificially supplies to the land

Question 7

Soil salinization

Answer 7

Salt buildup in the soil

Question 8

Deforestation

Answer 8

Destruction or loss of forests

Question 9

Reforestation

Answer 9

Replacing process of forests

Question 10

Acid rain

Answer 10

Polluted rain that can damage trees and kill fish in lakes

Question 11

Aqueducts

Answer 11

Artificial channels for transporting water

Question 12

Aquifers

Answer 12

Wells are drilled to the depth of rock layers where groundwater is plentiful

Question 13

Fossil water

Answer 13

Groundwater that is not replenished by rain

Question 14

ore

Answer 14

The mineral bearing rock to a processing plant where the valued mineral is removed

Question 15

Fossil fuels

Answer 15

Formed from the remains of ancient plants and animals

Question 16

Petrochemicals

Answer 16

Raw materials of many explosives

Question 17

Hydroelectric power

Answer 17

Electricity produced by moving water

Question 18

Geothermal energy

Answer 18

The heat of Earth’s interior