Ch.13 vocab

Question 1

an extremely thin, less dense solid covering over the mantle

Answer 1

crust

Question 2

a layer that makes up the majority of the earth and surrounds a small core of iron

Answer 2

mantle

Question 3

made up of the crust and outer mantle

Answer 3

lithosphere

Question 4

layer just below the outer mantle that is capable of flow

Answer 4

athenosphere

Question 5

concept that the outer layer of the earth consists of large plates composed of outer portion of the mantle

Answer 5

plate tectonics

Question 6

the breakdown of parent material into smaller particles that will become soil

Answer 6

weathering

Question 7

results from physical forces that reduce the size of rock particles, changes in temperature, wind, rain, snow, and moving water will cause this

Answer 7

mechanical weathering

Question 8

chemical alteration of rocks causing them to oxidize and break down over time

Answer 8

chemical weathering

Question 9

process of loosening and redistributing particles of soil over the landscape

Answer 9

erosion

Question 10

a thin covering over the land consisting of a mixture of minerals, organic material, air, water, and organisms

Answer 10

soil

Question 11

part of the world not covered by ocean

Answer 11

land

Question 12

ancient layers of rock often from mountains and hills

Answer 12

parent material

Question 13

organic material from the decay of dead plant and animal material

Answer 13

humus

Question 14

particles between .05 and 2.0 mm in size

Answer 14

sand

Question 15

particles less than .002 mm in diameter

Answer 15

clay

Question 16

ideal soil for agricultural use, a specific combination, of sand, silt, and clay

Answer 16

loam

Question 17

the various ways that soil particles clump together, how they stick to one another

Answer 17

soil structure

Question 18

soil structure determined by soil structure and moisture content, crumbles easily

Answer 18

friable

Question 19

series of horizontal layers in the soil that differ in chemical composition and physical properties

Answer 19

soil profile

Question 20

each recognizable layer of soil that differs in composition is identified

Answer 20

horizon

Question 21

undecomposed or somewhat decomposed organic matter found on the ground of forests

Answer 21

litter

Question 22

water moving down through the soil and carrying with it organic materials and minerals

Answer 22

leaching

Question 23

tilling the land at right angles to the slope in order to prevent erosion

Answer 23

contour farming

Question 24

the planting of different crops in strips to reduce erosion and produce a variety of crops

Answer 24

strip farming

Question 25

level areas constructed on a hillside to increase land usable for farming

Answer 25

terraces

Question 26

low lying ground that collects water as it flows downhill, streams and rivers

Answer 26

waterways

Question 27

planting of trees that protect bare soil from the full force of the wind

Answer 27

windbreaks

Question 28

a tillage method that usually leaves 15 to 30 percent of the land covered with crop residue

Answer 28

reduced tillage

Question 29

increases the amount of surface covered by crop residue to up to 50 percent

Answer 29

conservation tillage