Q2_LESSON 2_ SOIL RESOURCES Flashcards
Important in sustaining man’s existence, and provides humans with the following services
1. Arable land for agriculture
2. Regulating water and filtering potential pollutants
3. Nutrient cycling
4. Foundation and support
5. Mineral Deposits
Upper- most (relatively thin) layers of the Earth’s crust.
Soil
- the soil mantle of the Earth
- Foundation of terrestrial life
Pedosphere
Components of soil
(NPK)
Nitrogen
Phosphorous
Potassium
Components of soil
(percentages)
45% Mineral
25% Air
25% Water
5% Organic Matter
- Soil forms when rocks weathers
- May be slow or rapid
Soil formation
Factors of soil formation
- Parent material: Source/ Origin
- Climate: Long term of weather
- Topography: Physical feature of an area
- Biological factor: Animals and microorganisms
- Time: Long and continous process
Relative size of soil particles
Soil texture triangle
Soil triangle
- Big
- 0.05mm - 2.00 mm
Sand
Soil triangle
- Middle
- 0.002 mm - 0.05 mm
Silt
Soil triangle
- Smallest
- Less than 0.002 mm
Clay
Soil profile
- Mostly organic matter and humus
O Horizon (Surface litter)
Soil profile
- Dark
- High concentration of organic matter
A Horizon (Topsoil)
Soil profile
- Lighter
- Suspended materials move downward
E Horizon (Zone of leaching)
Soil profile
- Light- colored (Yellowish)
- Denser and less fertile than Horizon E
B Horizon (Subsoil)
Soil profile
- Below the roots
C Horizon (Weathered parent material)