Funday Times

COASTAL ECOSYSTEMS - MANGROVES
These ecosystems are confined to salt water areas of tidal regions. Thus, all flora and fauna are tolerant of high salt concentrations.

In addition, mangrove flora display several unique adaptations, which include prop roots to withstand tidal variations, aerial roots or, pneumatophores to overcome oxygen deficiency, and viviparity to increase survival rates.

Mangroves are extremely important ecosystems. They protect and stabilize the shorelines of estuaries and lagoons from erosion. In doing so, they prevent siltation of marine ecosystems such as Coral Reefs and Sea Grass Beds. Due to their unique position -i. e. because they are found between freshwater and salt water ecosystems, the species richness of both flora and fauna is very high. The larval and young stages of many marine species are found in mangroves.

Mangrove ecosystems provide food (many crustaceans and molluscs are found in mangroves) firewood and timber, and medicines, as well as other uses.

Only around 8600 ha of mangroves are left in the coastal areas of Sri Lanka. Rekawa and Kadolkele are two of the popular mangrove sites.

Mangroves are under threat from land reclamation for development, conversion to aquaculture and agriculture and over exploitation of selected species.

KEY for MANGROVES

1. Bruguiera gymnorhiza -a common mangrove tree
2. Rhizophora mucronata -a common mangrove tree
3. Black-crowned Night Heron ( Nycticorax nycticora )
4. Knee roots of Bruguiera gymnorhiza
5. Prop roots of Rhizophora mucronata
6. Telescopium telescopium -a common mollusc in mangrove areas
7. Little Egret
( Egretta garzetta )
8. Oysters ( Saccorstrea spp. )
9. Mud Lobster ( Thalassina anomala)
10. Pied Kingfisher
(Ceryle rudis )
11. Grapsid Crab
( Metapograpsus messar )
12. Whiskered Tern
( Childonius hybridus )
13. Common Sandpiper
( Tringa hypoleucos)
14. Ilaththi ( Scatophagus argus)
15. Pneumatophores
( Aerial Roots)
16. Archer Fish
( Toxotes chatareus )
17. Fingerlings

Information by Forest
Department
Coordinated by Duminda Sanjeewa Balasooriya

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