1. Weathering and Organic Processes from soil
What are some reasons that you use soil in your everyday life?

2. Weathering and Organic Processes from soil
Soil is a mixture of four materials: weathered rock particles, organic matter, water, and air.
Each soil is different depending on where the rock particles cam from.

3. Weathering and Organic Processes from soil
Water and air make up about 20-30% of a soils volume.
5% comes from organic matter which is remains and wastes of plants, animals, and other living organisms.

4. Weathering and Organic Processes from soil
What type of soil that forms in an area depends upon the following factors:
The type of rock in the area
The area’s climate
Landforms in the area
Plant cover
Time
Animals and other organisms

5. Weathering and Organic Processes from soil
What are the differences between the two soils, think about how soil is made.

6. Weathering and Organic Processes from soil
Why do you think soil is made up of different materials as you dig deeper?
As you dig you will find less organic and weathered material in the soil

7. Weathering and Organic Processes from soil
Climate will control what types of soil you find in that area.
The shape of the land also affects soil. Mountainous regions can be very different from soils found in valleys. Why?

8. Weathering and Organic Processes from soil
There are four world soil types
1. Tropical Soils
2. Desert Soils
3. Temperate Soils
4. Arctic Soils

9. Weathering and Organic Processes from soil
Tropical soils from in warm, rainy regions. Heavy rains wash away minerals, leaving only a thin surface layer of Humus. Tropical soils are not suitable for growing most crops.

10. Weathering and Organic Processes from soil
Desert Soils form in dry regions. These soils are shallow and contain little organic matter. With the low rainfall, chemical weathering and soil formation occur very slowly.

11. Weathering and Organic Processes from soil
Temperate soils from in regions with moderate rainfall and temperatures. Some temperate soils are dark colored, rich in organic matter and minerals and good for growing crops.

12. Weathering and Organic Processes from soil
Arctic soils form in cold, dry regions where chemical weathering is slow. They usually don’t have well developed horizons.

13. Weathering and Organic Processes from soil
Living Organisms affect the characteristics soil
Plants break down to form Humus and trees add to organic matter as they are broken down
Microorganisms include decomposers such as bacteria and fungi
These microorganisms decompose plants and animals that give nutrients to the soil

14. Weathering and Organic Processes from soil
Animals loosen and mix the soil they also add to the soil when their bodies decompose.

15. Weathering and Organic Processes from soil
Properties of soil can be measured.
Texture of soil is determined by the size of weathered rock and the particles around it.
The color of soil comes from iron and humus content.
Pore space refers to how much space is between the soil particles.

16. Weathering and Organic Processes from soil
Chemistry is another property of soil.
Plants absorb the nutrients they need from water in the soil