Science Ch.2 Sec1-4

Front 1

Weathering

Back 1

is the process that breaks down rock and other substances on at Earth's surface

Front 2

Erosion

Back 2

is the movement of rock particles by wind, water, ice and gravity

Front 3

Mechanical weathering

Back 3

the type of weathering in which rock is physically broken into smaller pieces

Front 4

Ice wedging

Back 4

the process that splits rock when water seeps into cracks, then freezes and expands

Front 5

Chemical weathering

Back 5

is the process that breaks down rocck through chemical changes

Front 6

Permeable

Back 6

a material that is full of tiny, connected air spaces that allow water to seep through

Front 7

Soil

Back 7

is the loose weathered material on Earth's surface in which plants can grow

Front 8

Bedrock

Back 8

is the solid layer of rock beneath the soil

Front 9

loam

Back 9

soil that is made up of about equal parts of clay, sand, and silt

Front 10

soil horizon

Back 10

is a layer of soil that differs in color and texture from the layers above or below

Front 11

topsoil

Back 11

a crumbly dark brown soil that is a mixture of humus, clay and other minerals

Front 12

sub soil

Back 12

the layer of soil beneath the top soil that containjs mostly clay and other minerals

Front 13

litter

Back 13

the loose layer of dead p,ant leaves and stems on the surface of the soil

Front 14

decomposers

Back 14

are the organisms that break the remains of dead organisms into smaller pieces and digest them with chemicals

Front 15

SOD

Back 15

thick mass of tough roots at the surface of the soil-kept the soil inplace and held onto moisture

Front 16

dust bowl

Back 16

the area of the great plains where wind erosion caused soil loss during 1930's

Front 17

soil conservation

Back 17

is the management of soil to prevent it destruction

Front 18

contour plowing

Back 18

is the practice of plowing fields along the curves of a slope

Front 19

conservation plowing

Back 19

soil conservation method in which the dead stalks from the previous year's crop are left in the ground to hold the soil place

Front 20

abrasion

Back 20

the grinding away of rock by rock particles carred by water, ice, wind, or gravity

Front 21

humus

Back 21

dark colored organic material in soil