Soil Forming Factors

Question 1

What are soil forming factors?

Answer 1

The things that affect the way soil is being made or formed all the time☺️

Question 2

How many years does it take to form 10mm of soil?

Answer 2

200 years

Question 3

Name the five main soil forming factors.

Answer 3

• topographical/ Geographical factors ( R)
• Climatic factors ( CL)
• Biological factors ( O)
  -Parent material ( P)
• Time( T)

Question 4

What are geographical factors? Why are they important?

Answer 4

They are the shape of land and affect where the soil is formed

Question 5

Name features of geographical factors?

Answer 5

Aspect or direction
Altitude or height
Angle of slope

Question 6

What is altitude? How does it contribute to soil formation?

Answer 6

It is the height of land above sea level.

Temperatures on the upper surface are very extreme and fluctuate continuously. They are cold at night and very hot in the day. The continuous contraction and expansion of rocks on mountains causes the rocks to weaken and over time weather

Question 7

What is the angle of slope? How does it affect soil formation?

Answer 7

It is how steep or gradual/ gentle the slope is. The is more soil formation on gentle slope that steep slopes because gentle slopes hold on to water and when mixed with water they cause hydrolysis

Question 8

What is aspect or direction? How does it affect soil formation?

Answer 8

It is the direction that the slope faces.

Slopes facing the north are warmer and evaporation rate is higher rather than South facing slopes that are wetter and cooler. The is more weathering on South facing slopes because of hydrolysis and carbonation. The amount of rain also affects the decomposition process

Question 9

Which slopes weather more? Facing towards the sea or away from the sea.
Why?

Answer 9

Towards the sea.

Because the amount of rainfall they receive is higher than those facing away from the sea resulting in hydrolysis and carbonation

Question 10

What are climatic factors?

Answer 10

Factors that affect the long term weather patterns of an area.

Question 11

Name the climatic factors.

Answer 11

Temperature
Rainfall
Wind
Sunlight
Humidity

Question 12

How does temperature and rainfall affect soil formation?

Answer 12

Fluctuating temperatures causes rocks to expand and contract continuously weakening them and then they eventually crack and begin to weather

Rainfall affects soil formation by hydrolysis and carbonation which weakens the rocks and make them weather leading to soil formation

Question 13

How does wind and sunlight contribute to soil formation?

Answer 13

Wind speeds up soil formation and weathering by blowing particles from one place to another.

Sunlight affects soil formation by hotter temperatures and moisture leading to faster decomposition and weathering

Question 14

How does humidity contribute to soil formation?

Answer 14

It increases the rate of decomposition of organic matter

Question 15

What are biological or organisms factor?

Answer 15

They are factors caused by living organisms that contribute to soil formation.

Question 16

List the biological factors that contribute to soil formation.

Answer 16

Vegetation
Animals
Mesofuana
Human activities

Question 17

How does vegetation contribute to soil formation?

Answer 17

Plant roots penetrate through rocks causing them to widen and eventually crack.they result in weathering and soil formation.

When plants die they add organic matter and minerals to the soil, (humus) which is the first layer Of horizon in the soil

Question 18

What is the function of plant roots?

Answer 18

They hold the soil together. Reducing erosion and making the soil stable

Question 19

What is mesofuana?

Answer 19

Medium sized organisms that live in the soil.

Question 20

Give examples of mesofuana

Answer 20

Nematodes and mites and beetleworms

Question 21

How do micro organisms contribute to soil erosion?

Answer 21

They break down organic matter and nutrients leading to decomposition.

Question 22

Give examples of micro organisms that live in the soil

Answer 22

Fungi
Bacteria
Termites

Question 23

How do mesofuana contribute to soil formation

Answer 23

The beetleworms and earthworms mix organic matter and rock particles leading to soil formation.

They bring air to the soil when they burrow and move around

Question 24

What agricultural activities contribute to soil formation

Answer 24

Planting vegetation
Leaving bare soil covered with mulch

Question 25

What is parent material

Answer 25

The underlying geological or bedrock that from which soil horizons form

Question 26

Give examples of how parent material can be formed

Answer 26

When particles are blown from one place to another

When rocks weather or humus is formed

Question 27

What determines the properties of the soil during early stages of parent material.

Answer 27

Character and chemical composition

Question 28

What are the soluble-ions in parent material?

Answer 28

Magnesium, Potassium, sodium and calcium

Question 29

What are the properties of the soluble ions in parent material

Answer 29

Available to plants
Easily dissolved in water

Question 30

What has a direct impact on soil chemistry and fertility

Answer 30

Parent material composition

Question 31

In what weather/ climate conditions does soil formation occur the most?

Answer 31

Warm and wet conditions

Question 32

How many years does it take to form 2cm of soil

Answer 32

1000 years

Question 33

Does time affect how quickly soil forms?

Answer 33

No, it is the type of soil and environment that determines it. Soil in another area can form faster than soil in another area in the same span of time

Question 34

How long does it take to form 1m of soil in tropical African countries

Answer 34

75000 years

Question 35

How many years does it take to form 10mm of soil in South Africa

Answer 35

300 years

Question 36

What is the difference between soil formation in other countries and south Africa which 10mm

Answer 36

100 years
300-200=100 years

Question 37

Why does it take longer for soil to form in South Africa

Answer 37

Because it’s exposed to humid and hot climate so it takes a lot of time for lichens to hold on to the soil and begin weathering process

Question 38

Why is time important in Soil formation

Answer 38

It determines the seasons and how long each period has

Question 39

Which horizon takes less time to develop

Answer 39

Surface horizon

Question 40

What is steady soil state?

Answer 40

When the horizon and properties do not change for long periods of time

Question 41

Name 3 things that occur in the soil over time

Answer 41

Thicker horizons sink deep into parent material

The is an increased iron accumulation in the soil which makes the soil redder

The is increased acidity