1. Lichen
Sarita
Department of Botany
DAVCG, Yamunanagar.

2. ~~Content~~ 1.Introduction 2.methodology 3.type of lichen
4.Accumulation of poison substance along the food chain
5.data analysis
6.factor affect growth of lichen
7.conclusion
8.photo of lichen

3. Lichen Structure of algae and fungus Algae Fungus – blue or green
- appears as clusters or chains
of greenish cells
- middle layer
Fungus
– brown or colourless
- long cellular threads called hyphae
-upper and lower layers

4. Relationship between algae and fungus
- Mutualism - both gain benefits
-Algae produce carbohydrates as food supply
- Fungus with hyphae holes the structure firmly on substrates and absorb mineral salts

5. CRUSTOSE LICHEN (e.g. Buellia 黑瘤衣 )
-Thin crust on the surface of tree, trunks, rock or soil.
-In most cases, crust adheres tightly as hyphae
penetrate the surface of substration.
(function : removal difficult )
(e.g. Buellia
黑瘤衣 )

6. Leafy lichen (e.g.Parmotrema 裸緣梅衣) -more complicated layered structure
-made up of flat lobes of tissue
-anchored by root-like rhizines.
(e.g.Parmotrema 裸緣梅衣)

7. Scaly lichen (e.g.Dirinaria 脊衣) -more complicated layered structure
-made up of flat lobes of tissue
-anchored by root-like rhizines.
-simpler form
-almost crustose form
-lobes of scaly lichen are of the order 1mm across whilst those of leafy lichen
(e.g.Dirinaria 脊衣)

8. Bushy lichen (e.g. Cladia 篩蕊) -highly organized
-stand erect or hang suspended
from the substrates
-thread-like, stalk-like or bushy
in form
-function: provide strengthening
tissue for support
(e.g. Cladia 篩蕊)

9. Indicator of air pollution( presence of sulphur dioxide in air
Reasons that lichen is an indicator of air pollution:
-plants have different of tolerance to sulphur dioxide
-lichen obtain of water mainly from air
-lichen easily dies in a small trace of sulphur dioxide in air
-lichen is sensitive to polluted air with sulphur dioxide

10. Different lichens have different tolerance to polluted air :
1. Lichen with large surface area to the volume ratio are more sensitive to the amount of sulphur dioxide
2.Shapes of lichen that related to tolerance to polluted air
i. Crustose (e.g. Buellia 黑瘤衣 )
ii. Bushy (e.g. Cladia 篩蕊 )
iii.Leafy (e.g.Parmotrema 裸緣梅衣)
iv.Scaly (e.g. Dirinaria 脊衣 )

11. 3. Bushy: Largest surface area to volume ratio, therefore most sensitive to amount of sulphur dioxide in air
Encrusting: Smallest surface area to volume ratio, therefore less Sensitive to amount of sulphur dioxide in air.

12. Accumulation of poison substance along the food chain:
A.Bio accumulation:
lichen absorbs oxygen and water from air sulphur dioxide is also absorbed sulphur dioxide cannot be removed and thus accumulate lichen absorb sulphur dioxide thruoghout their life and accumulate in their bodies.
Accumulation to certain extent will kill lichen

13. B. Bio magnification: Food chain of lichen:
Sunlightlichen (algae)snailshuman beings
Sulphur dioxide is accumulated in lichen
Snails feed on large amount of lichen and thus
the sulphur dioxide obtained during feeding
multiply.

14. Human beings feed on large amount of lichen and thus the effect on Magnification of sulphur dioxide is more obvious.
Ways to reduce the effect of accumulation
of toxic substance:
As the accumulation of toxic substances in lichen will finally harm and endanger human beings, it is necessary to reduce the sulphur dioxide level in air.Reduce the sulphur dioxide content in air by reducing air pollution

15. Thank You….