Soil

Question 1

Soil

Answer 1

the natural product formed from weathered rock by the action of climate and living organisms.

Question 2

pedon

Answer 2

a three-dimension soil body large enough to study all physical and chemical properties and all horizons

Question 3

soil profile

Answer 3

any vertical cut through a body of soil or pedon

Question 4

horizons

Answer 4

apparent layers of soil

Question 5

spodosol

Answer 5

is found in cool humid regions; coniferous forests

Question 6

O

Answer 6

the “o” horizon is the surface layer, formed above the mineral layer and composed of fresh or partially decomposed organic material that has not mixed into mineral soil

Question 7

A

Answer 7

the “A” horizon is the upper layer of mineral soil with a high content of organic matter
It is characterized by an accumulation of organic matter and the loss of some clay, inorganic minerals and soluble matter

Question 8

E

Answer 8

the “e” horizon is the zone of maximum leaching
characterized by the development of granular, platelike, or crumblike structures

Question 9

leaching

Answer 9

is the loss of minerals due to water

Question 10

B

Answer 10

the “b” horizon is the zone of illuviation, or collection of leached material
it accumulates silicates, clay, iron, aluminum, and humus

Question 11

C

Answer 11

the “c” horizon contains weathered material, either like or unlike the material from which the soil is presumed to have developed
this layer is little affected by soil formation

Question 12

R

Answer 12

bedrock

Question 13

Soil texture

Answer 13

determined by the proportion of particle size classes
-sand .05 to 2.0mm
-silt .002 to .05
-clay less than .002mm

Question 14

which soil holds the most water

Answer 14

clay

Question 15

loess

Answer 15

soil is transported by wind

Question 16

alluvial

Answer 16

soil transported by streams

Question 17

till

Answer 17

soil transported by ice

Question 18

lacustrine

Answer 18

soil developed in a lake

Question 19

marine

Answer 19

soil developed in an ocean

Question 20

how is soil formed?

Answer 20

formation of soils begins with the weathering of rocks and their minerals
mechanical weathering
under the action of water, wind and temperature change the rock surface flakes and peels away
lichens and plants colonize the weathered material
plant roots penetrate and further break down the parent material
plant debris enables bacteria, fungi, earthworms, and others to colonize the area
animals like earthworms consume fresh material and leave partially decomposed products
compounds break down into inorganic products
humus remains

Question 21

aluminosilicates

Answer 21

calcium, potassium, and sodium

Question 22

humus

Answer 22

is chemically complex organic material. the formation of humus in soil is strongly influenced by the climate

Question 23

Fossorial animals

Answer 23

rodents of the family Bathyergidae which made these mounds are the African mole rates and all are fossorial

Question 24

All soil development processes will occur faster in

Answer 24

warm wet climates than in cool dry climates