Soil Profile and Soil Formation

Soil Formation ​

Weathering of Rock​

• Weathering (discussed in Lesson 1) ​is the breakdown of rock into smaller pieces. This is how soil is formed.

• Living things help to add nutrients to the soil, and break down materials.

• Soil is different, depending on location, around the world.

The soil that develops from parent material that has been moved far from its original location ​

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Transported Soil ​

The soil where the parent material is the local bedrock ​

Residual Soil​

Soil Layers​

• The vertical sequence of soil layers.

• Think of a chocolate trifle!

• The 4 major layers are O, A, B, and C​.

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​Soil Profiles

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​https://www.youtube.com/watch?v=lgoLzst6jw0

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• Will soil contain enough nutrients to grow plants

• Introduction of fertilizers ​

​Fertility

• Based on size

• Clay, silt, or sand

• Clay is the largest​

​Texture

• Dependent on horizons

• Dark = rich in organic material

• Red/yellow = oxidation of iron materials

• Gray/blue = poorly drained​

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​Soil Color

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