Soil Profile

Question 1

____________ of different layers of soil observed from the surface down to the underlying rock

Answer 1

vertical arrangement

Question 2

each layer is called ___________ and they have distinct characteristics formed through soil formation processes

Answer 2

horizons

Question 3

the 3 major horizons

Answer 3

A horizon
B horizon
C horizon

Question 4

also known as the A horizon

Answer 4

topsoil

Question 5

a major horizon in which it is a mixture of minerals and organic material

Answer 5

A horizon

Question 6

a major horizon in which it is essential for plant growth and dark due to the organic matter

Answer 6

A horizon

Question 7

a major horizon in which it is the center of biological activity, where plant roots and soil organisms are abundant

Answer 7

A horizon

Question 8

also known as the B horizon

Answer 8

subsoil

Question 9

a major horizon in which it contains minerals

Answer 9

B horizons

Question 10

examples of minerals in B horizon

Answer 10

iron, aluminum, and clay deposited from above

Question 11

a major horizon in which it is denser than A horizon with less organic material

Answer 11

B horizon

Question 12

a major horizon in which it acts as a reservoir of minerals for plants

Answer 12

B horizon

Question 13

also known as the C horizon

Answer 13

parent material

Question 14

a major horizon in which it is partially weathered rock

Answer 14

C horizon

Question 15

the other horizons in soil profile

Answer 15

O, E, R horizon

Question 16

also known as the O horizon

Answer 16

Organic Layer

Question 17

a horizon in which it is decomposing organic material (i.e. leaves, grass, and other plant debris)

Answer 17

O horizon

Question 18

a horizon in which it is the topmost layer

Answer 18

O horizon

Question 19

also known as the E horizon

Answer 19

Eluviation Layer

Question 20

a horizon in which it lacks minerals and organic matter due to leaching

Answer 20

E horizon

Question 21

a horizon in which it is the light-colored or grayish layer

Answer 21

E horizon

Question 22

the process of water carrying materials downward

Answer 22

leaching

Question 23

also known as the R horizon

Answer 23

Bedrock

Question 24

a horizon in which it is a solid rock

Answer 24

R horizon

Question 25

a horizon in which it is unaffected by weathering

Answer 25

R horizon

Question 26

a horizon in which it is the bottommost layer of the soil profile

Answer 26

R horizon

Question 27

5 human activities that degrade soil quality

Answer 27

soil erosion, soil compaction, desertification, intensive agriculture, and urbanization

Question 28

a human activity that degrade soil quality in which it is the process that the soil particles are loosened or washed away in the valleys, oceans, rivers, streams or faraway lands

Answer 28

soil erosion

Question 29

a human activity that degrade soil quality in which it is a non stoppable process that occurs either slowly at a higher rate

Answer 29

soil erosion

Question 30

a human activity that degrade soil quality in which the roots hold the plants

Answer 30

soil erosion

Question 31

a human activity that degrade soil quality in which it is caused by too much rain

Answer 31

soil erosion

Question 32

a human activity that degrade soil quality in which it causes the loss of topsoil and nutrients in the soil.

Answer 32

soil erosion

Question 33

a human activity that degrade soil quality in which it is indeed the most visible effect of soil degradation

Answer 33

soil erosion

Question 34

a human activity that degrade soil quality in which it is a natural process but is often made much worse by poor management practices.

Answer 34

soil erosion

Question 35

a human activity that degrade soil quality in which it reduces the amount of air, water, and space available to roots and soil organisms

Answer 35

soil compaction

Question 36

a human activity that degrade soil quality in which it is caused by repeated traffic or traveling on wet soil.

Answer 36

soil compaction

Question 37

a human activity that degrade soil quality in which it is the irreversible change of the land to such a state where it can no longer be recovered for its original use

Answer 37

desertification

Question 38

a human activity that degrade soil quality in which it is characterized by droughts and arid conditions as a result of human activities and exploitation

Answer 38

desertification

Question 39

a human activity that degrade soil quality in which it is a major threat to world soils and currently affects about one-sixth of the world’s population and a quarter of the world’s land.

Answer 39

desertification

Question 40

a human activity that degrade soil quality in which it has been increasing since the 1960s in an effort to feed the world population more efficiently

Answer 40

intensive agriculture

Question 41

a human activity that degrade soil quality in which it led to the use of more and heavier machinery, deforestation, and clearing of land for cultivation

Answer 41

intensive agriculture

Question 42

a human activity that degrade soil quality in which it led to the loss of organic matter, soil compaction, and damage to soil physical properties.

Answer 42

intensive agriculture

Question 43

a human activity that degrade soil quality in which it led to contaminated soil and water supplies, leading to further loss of soil fauna and flora which are essential parts of a healthy soil.

Answer 43

intensive agriculture

Question 44

a human activity that degrade soil quality in which it is the increasing population has led to the conversion of land to urban centers which are generally characterized by concrete structures, roads, and pavements.

Answer 44

urbanization

Question 45

a human activity that degrade soil quality in which these concrete structures represent a significant loss of soil, which is more or less permanent as soil is sealed with concrete.

Answer 45

urbanization

Question 46

a human activity that degrade soil quality in which such sealing hinders the soil’s interaction with the atmosphere, hydrosphere, and biosphere which affects nutrient cycling and other soil services.

Answer 46

urbanization