Weeks 3 & 4 | Forest Soils & Rhizospere
October 3rd, 2009 at 17:18by Alison Cole
What is the rhizospere? It is the area where root hairs of trees and other plants interact with the soil. “This is a special place because hair roots bring food and oxygen, enabling the micro organisms to work faster than anywhere else. A continuous flow of water is caused, as water is absorbed by these roots, drawing with it dissolved substances”, such as nutrients, salts and occasionally toxins (Anthoni, 2000).
Although the rhizoshpere is a much smaller ecosystem than that above ground, its functions are crucial to life under and above the soil. This “micro” habitat is home to a large community of microorganisms, fungi, and bacteria.
The removal of trees has a drastic effect on soil composition. While the tree roots physically hold the soil in place and draw water to the surface, the diagram above shows that these root systems support a diverse, but fragile ecosystem (the rhizospere).
The figure above shows soil and carbon (organic/decayed matter which the main ingedient of soil) degradation in New Zealand after forest clearance for agriculture. In your readings and research, what are some examples of deforestation and soil degredation? How about reforestation, and the renewal of soil?
Here are some quick videos from HippoCampus.org. Check out the syllabus for many new web & multimedia resources, as well!
References
- Soil Ecology (Dr. J Floor Anthoni, 2000)