Lichens: interaction fungialgea

1
Lichens interaction fungi/algea
2
Physiology of lichens

• Symbiotique association between a fungi and a
  algea
• The lichen fungus protect the algea against the
  dryness and provides mineral compounds from the
  substratum.
• Minerals come from rain solutes or surface water
  flow.

3
Physiologie of lichens

• The lichen algea supplies organic compoumd via
  photosynthesis.
• Parasitic symbiosis

4
Ecology of lichens

• 8 of emerged lands
• 20 000 to 30 000 species in the world
• First to settle in places lacking soils

5
Ecology of lichens

• Lichens occur in cold and temperate regions
• Grow on stable surfaces (rock, trees, soils)
• Can survive on tough conditions of deserts and
  frozen soils of the artic region
• Really resistant to dryness

6
Use of lichens

• Medical uses
• Industrial uses
• Bioindicators to
• - pollutant level
• - forest management
• - chemestry of soils