1. Mangroves also known as Mangal
from mangue (tree) and grove (stand of trees) (Portuguese)
Replace salt marsh as the dominant coastal ecosystem in subtropical and tropical regions
Facultative halophytes

2. Distribution 240,000 km2 worldwide 2,700 km2 in Florida
68 spp worldwide
10 spp in the Americas

3. Distribution Continued
Found on coastlines between 25 N and 25S latitude, dependent on temperature
Rhizophora - survive 2-4 C for 24 hrs
Avicennia – survives 2-4 C for several days

4. Three Main Genera Rhizophora (red mangrove)
R. mangal and R. racemosa most common New World spp
High prop roots and dangling roots are common
More cold tolerant

7. 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

9. Lagunicularia (white mangrove)
L. racemosa most common in New World
Affinity for lower salinity areas

11. Geomorphological settings
need gentle wave/tidal action to bring nutrients
salinity allows them to out compete FW species

13. Hydrodynamic settings
Fringe – protected shorelines, some canals, rivers and lagoons
Grow to 13 m tall
Accumulate organic matter
Found in S. Fla, Puerto Rico, Mexico, Texas
Avicennia found in salinity to 59 ppt, Rhizophora to 39 ppt
Overwash islands – one type of fringe mangrove
Rhizophora dominated
sensitive to ocean pollution

14. b. Riverine – along tidal affected rivers
Grow to 21 m tall
Rhizophora dominated, but with few prop roots
Avicennia and Lagunicularia also present
Salinity ppt

15. c. Basin- inland depressions, behind fringe, in stagnant water
Grow to 9m tall
Soil conditions: highly anoxic, saline
Avicennia and Lagunicularia with many pneumatophores
If salinity >50ppt: Avicennia, if low: Lagunicularia, 30-40ppt mixed forest

16. d. Dwarf – isolated, low productivity, low FW, low nutrients
Grow to 2-5m shrubs
Fringe of everglades, Florida Keys
Hammock – one type
buildup of peat
Rhizophora dominated

17. E. Understory – lacking due to variety of stressors
Mangrove ferns (Acrostichum spp) are common, 3 spp worldwide

18. F. Salinity Not required for mangroves
Much higher in soil than in water

19. G. Zonation

23. H. Adaptations Salinity – exclusion and excretion
Prop roots and drop roots – Rhizophora
Pneumatophores – Avicennia – cm above sediment
Lenticels found on a & b, let oxygen into plant, moves through arenchyma to root rhizosphere
Viviporous seedlings – Rhizophora – seeds germinate on tree
i. Hypocotyls (seedling) drops, floats till touches sediment, roots

24. Crabs – mangrove maintenance
Burrow, oxygenate soil, drag leaves into soil, aid in decomposition
Selectively eat dropped hypocotyls

25. J. Hurricanes

26. Hurricanes Continued
mangrove succession to stable community in average time between major hurricanes
Wipe out larger mangroves, small trees in gaps survive and act as a seed bank

27. K. Mangrove effects on estuaries
Net export of organic matter and nutrients
Provides nursery areas and food sources for fisheries