1. Soils

2. Soil
Soil is the lose covering of rock particles and decaying organic matter(humus)
Results from both physical and chemical weathering

3. Parent Material
Parent material is the source of the mineral matter in soils
Parent material is important because:
It affects the rate of weathering
Chemical makeup affects the soils fertility

4. Time Time-The longer a soil has been forming the thicker it is.
As a soil gets older other characteristics affect the soil more than the parent material

5. Climate Climate has the greatest affect on soil formation
Variations in temperature and precipitation affect the rate, depth and type of weathering

6. Organisms Plants are the main source of organic matter
Plants release nutrients when they decay. Adds to the soils fertility

7. Slope Steep slopes have higher erosion. Little water can soak in.
Soils are thin on steep slopes

9. Characteristics of Soil
Soil Texture
Texture refers to the proportions of different particle sizes.
A. Sand (large size)
B. Silt – feels like flour
C. Clay (small size)
D. Loam (a mixture of all three sizes) is best suited for plant life.

10. Soil texture
Soils are composed of particles that can be sand, silt or clay sized.
Based on the soils % composition of each type of particle that determines the soils texture

11. Soil profile A soil profile is the vertical sequence of soil layers
Soil horizons are the distinct layers in a profile
The upper layers contain more organic material, the bottom layers contain more parent material