Life in Soil Flashcards
1
Q
What does loam soil contain?
A
- Mixture of clay and sand
- Large amount of partly decomposed animal and plant waste called humus
2
Q
What experiments can be performed to find out soil composition?
A
- Humus content found by burning humus off with a Bunsen burning and measuring the mass lost
- Air content found by seeing how much water is needed to fill the air spaces
- Water content found by slowly heating the soil to evaporate the water
3
Q
How does particle size affect soil?
A
- Larger particles have more air content and higher permeability
- Large amounts of humus have more air content and higher permeability
4
Q
What do organisms living in soil rely on?
A
- Oxygen for respiration
- Water for chemical reactions
5
Q
Why is humus in soil important for organisms?
A
- Decomposes to release minerals
- Increases the air content in the soil
6
Q
Why are earthworms important for soil structure and fertility?
A
- Bury organic material for decomposition by bacteria and fungi
- Aerate and drain the soil (allows organisms to respire aerobically)
- Mix up soil layers (dead material can be decomposed)
- Neutralise acidic soil (allows plants to grow in optimum pH)
