1. Soils Chapter

2. Today’s key terms
Soil
Mineral matter
Air
Water
Living organisms
Humus

3. What is soil
Soil is the thin layer of loose material on the earth’s surface.
Plants grow in it.
It is a natural resource.

4. What is soil made up of Mineral matter Air Water Living organisms
Humus

5. Mineral matter This is the largest ingredient in the make up of soil.
Mineral matter is the remains of rocks.
It looks like gravel and silt

6. Air Air is in the space between the soil particles.
Air is important for the growth of roots
It is also important in the formation of humus.

7. Water Water is important as it contains dissolved minerals.
These minerals provide plants with important nutrients that are required to grow.

8. Living organisms These included
Earthworms
Slugs
Woodlice
Insects
Bacteria
Fungi
The bacteria and fungi in the soil helps to break down dead plants to form Humus
This Humus increases the fertility of the soil

9. Humus Humus is the decayed creatures, plants and litter.
Humus provides the soil with nutrients.
Humus increases the fertility of the soil

10. Soil formation
Soil formation can be influenced different factors and they included
Climate
Parent Rock
Vegetation
Micro-organisms
Time
People

11. Soil formation Climate Vegetation Parent Rock Micro-organisms
All Mix to form
Soil
Time
People

12. Climate Climate affects the following
amount of rainfall
The temperature
All of this affects the amount of vegetation
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13. Parent Rock
Climate influences the amount of erosion/weathering that occurs to rock in a region
This influences the amount of mineral matter that is present in the soil.
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14. Vegetation Influenced by the climate The type of Vegetation
The amount of Vegetation
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15. Micro-organisms These Micro-organisms break down the vegetation
The amount of vegetation dictates the amount of humus in the soil
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16. Time
The amount of time soils is allowed form dictates the type of soil that forms.
It takes approx 400 years for 1cm of soil to form.
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17. People People can alter the formation of soil
Irrigation, drainage or fertilizing all make the soil more fertile OR
Overuse make the soil les fertile.
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18. Homework
Update all your notes
and
Question 1 on page 183

19. Today’s key terms revised
Soil
Mineral matter
Air
Water
Living organisms
Humus

20. Today’s Key Terms Soil profile Leaching Brown Soils Podzol Soils
Horizon
Leaching
Hardpan
Brown Soils
Podzol Soils
Peaty soils
Gley soils

21. Last classes terms revised
Soil
Mineral matter
Air
Water
Living organisms
Humus

22. Soil profile Soil is made up of different layers
Each layer is called a horizon
Each layer is labelled with a letter

23. Soil profile of a litter plant
Horizon A
This is the upper layer
It is made of topsoil
It has a high Humus content
It is dark in colour

24. Soil profile of a litter plant
Horizon B
Found underneath horizon A
It is called a subsoil
Less Humus more stones
Lighter colour

25. Soil profile of a litter plant
Horizon C
Is the layer of parent rock

26. Leaching
This is the washing of nutrients from one horizon to the other.
This can cause the loss of fertility in horizon A
If leaching is severe it can result in hardpan
This is grey in colour and is impermeable.
This can result in a field been very wet as water cannot soak into the ground.

27. Irish Soil There are four main types of Irish soils they include
Brown Soils
Podzol Soils
Peaty soils
Gley soils

28. Brown Soils Found in area where deciduous trees used to be.
Horizon A is rich in humus
Horizon B has a blend of horizon A due to worm action
Horizon C is made of bedrock
This is a very fertile soil

29. Podzol Soils Found in area where coniferous trees are found.
These are mainly found in cold climates
Horizon A has low levels of humus
Cold weather has limited worm activity
Between horizon A and horizon B a hardpan may develop.
Horizon C is made of bedrock
This is a very infertile soil

30. Gley Soils Develop in areas where the bedrock is impermeable.
Or there is a band of hardpan above the parent rock bed

31. Peaty soils Develop in high upland areas. Areas with high rainfall
Results in water logged land

32. Today’s Key terms Tropical red soil dd Climate Chemical weathering
Iron oxide Leaching
Infertile dd

33. Last classes Key Terms Soil profile Leaching Brown Soils Podzol Soils
Horizon
Leaching
Hardpan
Brown Soils
Podzol Soils
Peaty soils
Gley soils

34. Tropical red soils
Found in areas that have tropical or equatorial climates.
Formation influenced by hot, wet climatic conditions.

35. Tropical red soils Formation
The formation/make up of this soil is different to Irish soils.
Continuous leaf fall
Therefore thick layer of litter
This is broken down due to
Mirco-organisms
Hot, wet climatic conditions.

36. Tropical red soils Formation
The acid from the humus assists the weathering to the parent rock
The erosion is also aoded by the high temperatures
The weathering of the rocks breaks down the iron oxide in the soil.
This gives it a reddish colour.

37. Is the soil FERTILE OR INFERTILE
Tropical red soils
Is the soil FERTILE OR INFERTILE
Normal conditions very fertile due to continuous leaf fall.
HOWEVER
When the forest are cut away the soil suffers from leaching due to heavy rainfall.
This leads to the soil becoming infertile.

38. Natural vegetation and soil
Soil influences vegetation
The soils fertility dictates how much the vegetation grows
Vegetation influences soil
The vegetation dictates the amount of humus in the soil.

39. Soils influences on vegetation
Fertile soil
The more fertile the soil the more it can support strong growth.
Infertile soil
Lack of nutrients can limit the amount of growth that soil can support. Typical vegetation would include coniferous trees.
Soil depth
Trees such as oak and beech need a large depth of soil because of there deep roots and there need for nutrients.

40. Vegetations influence on soil
Humus role
Binds soil
Nourish soil
Influences the colour of horizon A
Vegetation reduces the effect of leaching
Roots absorb the leached nutrients
Vegetation reduces soil erosion
Roots bind the soil
Roots absorbs some of the water content in the soil.