1. SOIL

2. Definitions Bedrock – Solid, un-weathered base rock
Regolith – Broken up rock particles

3. 4 Components of Soil

4. Rock Material in Soil Sand - Largest component (2mm – 0.06mm)
Composition (parent material) = Quartz
Source = Mechanical weathering

5. Rock Material in Soil Silt (0.06mm-0.002mm)
Composition - feldspar & quartz
Source - mechanical weathering

6. Rock Material in Soil Clay - less than 0.002mm
Composition (parent material)– feldspar
Source – chemical weathering

7. Which soil is best?
Sandy Soil?
Pro vs. Con
Silty Soil?
Clay Soil?

8. Soil Sizes
Sand (largest)
Silt
Clay (smallest)
Loam (mix of all 3)

9. Soil Texture

10. TAKE OUT YOUR OBJ. NOTES Pick up your papers from back

11. Soil Profile
A cross section of soil showing the different layers (horizons)
Horizons
A (O)
B (E) C
DRAW THIS

12. SOIL PROFILE A- HORIZON: Organic material
B-HORIZON: area where nutrients from A are “leaching” down.
C-HORIZON: mostly parent bedrock, unweathered material.

14. SOIL HORIZONS
A- horizon top soil rich in organics humus- decaying leaves
B- horizon plant roots anchor here
C- horizon bedrock

15. Tropical - Rainforest Thin A + B
lots of chemical weathering, but nutrients are used quickly
why?

16. Desert Climate
thin A + B
little nutrients
little weathering
why?

17. Polar soil
thin A + B
few nutrients
little chemical weathering
why???

18. Temperate Climate Thick A + B lots of nutrients good farmland
lots of chem. + phys. weathering
why?

19. Importance of soil Food chain Filters groundwater
1 cm = 1,000 years formation
Providing resources for world to survive.