This document discusses mangrove forests and their ecological functions. It notes that mangroves provide habitat for fish, shellfish, and birds. They also protect coastlines and accumulate sediment. The document discusses the distribution of mangroves between 25 degrees north and south latitude. It describes the three main genera of mangroves - red, black, and white - and their characteristics. Mangroves have unique root systems and can tolerate high salinity. They are important ecologically by providing habitat and improving water quality, and economically by providing food, medicine and wood.

1. Mangroves
Marine Biotechnology – U2
Dr.Shaleesha A. Stanley
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2. Dr.Shaleesha A. Stanley
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3. About mangroves
 Mangrove forests perform multiple ecological functions such as
1. production of woody trees;
2. provision of habitat,
3. food, and
4. Spawning grounds for fin-fish and shellfish;
5. provision of habitat for birds and other valuable fauna;
6. protection of coastlines and accretion of sediment to form new land.
Mangrove areas have high biological productivity, associated with heavy leaf
production, leaf fall and rapid decomposition to form detritus
The mangrove ecosystem is dynamic, changing in both location and
composition, and has great resilience with the ability to restore itself after
heavy damage, as long as seed sources and water flow are maintained.
There are also many economic benefits from mangrove resources; like as a
source of firewood, self replenishing areas of fishery resources, for collecting
honey and for tourism.
Dr.Shaleesha A. Stanley
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4. Distribution
Found on coastlines between 25° N and 25°S
latitude, dependent on temperature
i.
ii.
Rhizophora - survive 2-4° C for 24 hrs
Avicennia – survives 2-4° C for several days
Dr.Shaleesha A. Stanley
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5. Dr.Shaleesha A. Stanley
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6. SPECIES OF MANGROVES-60 species
worldwide
Black Mangrove
Red Mangrove
White Mangrove

7. Three Main Genera
a.
Rhizophora (red mangrove)
a.
b.
c.
R. mangal and R. racemosa most common New
World spp
High prop roots and dangling roots are common
More cold tolerant
Dr.Shaleesha A. Stanley
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8. Dr.Shaleesha A. Stanley
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9. Avicennia (black mangrove)
i. A. germanaus most common in New World
 ii. Can tolerate very high salinity (60 ppt) and
very anoxic conditions
 iii. Known for having pneumatophores
Dr.Shaleesha A. Stanley
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10. Dr.Shaleesha A. Stanley
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11. Lagunicularia (white mangrove)
i.
ii.
L. racemosa most common in New World
Affinity for lower salinity areas
Dr.Shaleesha A. Stanley
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12. Dr.Shaleesha A. Stanley
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13. Characteristics of Mangroves
 Evergreen plants with thick leathery
leaves designed to minimize
transpiration.
 Viviparous germination where the
seed germinates on the tree and falls
down in the germinating condition with
a long radicle- characteristic of
Rhizophoraceae .
 Root system has many unique types
of roots.




1. Stilt-roots,
2. Pneumatophores,
3. Root knees.
4. Plank Roots

14. ROOTS
KNEED ROOTS-the
horizontal roots growing
vertically upwards and forming
loops downwards to resemble a
bent knee.
PLANK ROOTS-wavy,
snake-like roots that radiate
outwards from the trunk base.

15. Lenticels
Lenticels—small pores
present on aerial roots.
Lenticels are
susceptible to clogging
by crude oil and other
pollutants, and attacks
by parasites.

16. Do Mangroves need salt?
Facultative halophytes
Grow in fresh water +
salt water.

17. COPING WITH SALT
Exclude Salt (no intake)
Extrude salt (take salt
in and dispense it
through glands in their
leaves).

18. IMPORTANCE--ECOLOGICAL
Habitats, nurseries, and nesting sites.
Root systems –harbor many organisms that trap and
cycle nutrients and other chemicals.
Contribute to higher water quality.
Protect shorelines from erosion.

19. IMPORTANCE --ECONOMIC
Food--- edible fruits and honey from flowers of
some species. River mangrove—source of best
honey.
Medicines- Treatment of skin disorders and sores
including leprosy. Headaches, rheumatism,
snakebites, boils, ulcers, diarrhea, and many more
conditions are traditionally treated with
mangrove plants.
Hard wood -- used for boat building and cabinet
timber.

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