1. Chapter One
The Importance of Soil
Video

2. The Importance of Soil
Additional acreage is lost due to urbanization or degradation .
Soil is a nonrenewable resource

3. The Importance of Soil Most of the time we take soil for granted.
Soil is a very thin and often fragile layer of life supporting material.

4. The Importance of Soil What does living things need?
Proper temperature
Oxygen
Water
Carbon
Other nutrients
These factors are exchanged in the soil that allow elements to be recycled rather than lost

5. The Importance of Soil Oxygen: Plant roots need oxygen to grow.
Gases will pass in and out of the soil to supply the oxygen for the roots

6. The Importance of Soil Temperature
Plants will grow best in certain soil temperature ranges.
Most plants will root in temperature around degrees F.
Water:
Seldom stays in one place

7. The Importance of Soil Carbon:
Plant leaves collect sunlight to use the energy in the process of photosynthesis.
Which involves converting atmosphere carbon to biological carbon
Atmosphere carbon = carbon dioxide
Biological carbon = simple sugars

8. The Importance of Soil Nutrients :
Plant nutrients are chemicals a plant needs to grow.
There are two types of nutrients cycles
Nitrogen cycle
Mineral cycle

9. The Importance of Soil Nitrogen:
Comes directly from the atmosphere where it occurs as a gas that plants cannot use.

10. 4 Needs of Soil There are four needs of the soil Anchorage Water
Oxygen
Nutrients

11. 4 Needs of Soil Anchorage: Water:
This is where plants grow freely and are firmly supported or anchored so they can grow to reach the sunlight.
Water:
Soil will provide the plants with all the water the plant needs
Roots are the best water absorbing body .

12. 4 Needs of Soil
Oxygen:
All creature even plants need oxygen. Plants release oxygen during photosynthesis but consume it during respiration.

13. 4 Needs of Soil Nutrients:
There are 16 nutrients usually considered to be needed for plants.
Plants obtain 13 of the 16 nutrients from the soil itself.
Other nutrients come from Air and water.
Carbon
Oxygen
hydrogen

14. 3 phase system What is soil Matrix?
It is the arrangement of solid particles and pore spaces which consists of three phases of solid , liquid, and gases.

15. 3 phase system The ideal Soil Type: 50% solid material 25% water
45 % mineral particles
5% organic matter
25% water
25% gases

16. 3 phase system Root Growth: Water reaches the root by two ways
either water flows toward the root
Or the root grows into moist soil

17. Soil Particles
Sand: .05-2mm
Silt: mm
Clay: <.002 mm

18. Sand .05-2mm Sand drains easily = POOR ABILITY TO RETAIN MOISTURE
Little chemical activity = LITTLE NUTRIENT BONDING

19. Silt mm
Able to hold lots of water and gives water to plants easily
Little chemical activity = LITTLE NUTRIENT BONDING
May compact under heavy traffic = poor air and water movement

20. Clay
<.002mm
Water adheres very well to clay = HIGH ABILITY TO RETAIN MOISTURE
But can hold water so tightly plants can’t get it
Very chemically active = GOOD NUTRIENT BONDING

21. Soil Texture Ribbon Test
Used to determine what particles your soil is made up of
Loam- a fertile soil of clay and sand containing humus.
Ribbon test Video

22. Soil Texture Triangle
Video