Mangrove Ecosystem of Sri

LankaBy Pathum Weerawarna

Mangroves of Sri Lanka

Mangrove habitat is…….. -marshland -found in coastal area -with unique characters -differing from the freshwater swamps

and peat bogs in structure and function.

Introduction

•Dominated by highly adapted woody halophytes.•Inter tidal and supra tidal zone of muddy shores.•Designated as an energy subsidized ecosystem.

Distribution•Restricted to estuaries along the cost of Sri Lanka•Mangrove extent of SL is between 6000-7000 ha

Largest mangrove patch:Puttalam Lagoon- Dutch

Bay- Portugal Bay complex.(3385 ha)2nd Largest patch:

Patch in Batticaloa.(1520 ha)3rd Largest patch:

Patch in Trincomallee.(1020 ha)

Characteristic Features•Consist with lots of unique characters.

Temperature

-Always fluctuated

Humidity-High inside the Island-Low around the island

Soil-Poor in Oxygen-Loose sediment-Generally acidic-Particle size increases from shore-land-Ca2+,Mg2+> K+

Water-Fresh+Marine-High salinity-Flow rate & direction always change

Animals

Arthropoda Mollusca Chordata

Crustasea

Gastropoda

Bivalvia

Scylla serrata

(Kadol kakuluwa)

Thalasssina anomala

(Mud lobster)

Geloina coaxans

(Matti)

Cerithidea cingulata

(Uri)

Actinopterygi

Mud skipper

Aves

Red wttled lap-winged White brested water hen

Adaptations

Adaptations of Animals

Oysters attached to mangrove roots

Burrowing habit eg-Mud skipper

Mud skipper :Fins: to skip on land and water.Eyes: to see on land and water.Skin: additional respiratory surface

Terrestrial crabs:Adapted to live on land for a long time

Plants

Avicennia spp

Bruguiera spp

Rhizophora spp

Acanthus spp

Some Dominant plants

Adaptations of Plants

Adaptations

Physical stability-Prop roots-Stilt roots

Salt tolerance -Salt Glands

Anaerobic SedimentPneumatophores -Pencil like -knee roots -Stumpy

Pencil like

Reproduction-Viviparity

Hypocotyle (Bruguiera)

Ecological Significant

•Protect the shores of estuaries and lagoons against erosion.•Reduce siltation of lagoons.•Protect near by ecosystems such as coral reefs and sea grass beds.•Absorb pollutants.•Serve as the feeding grounds and the habitat for juveniles of marine fish.•Nursery grounds for prawns.

Human Impact on Mangroves

People get lots of benefits from aquatic and terrestrial components of Mangrove ecosystem.

Mangroves

Foods and beverages

Firewood and timber

Mats and Baskets

Tannin

Lime

Agriculture

Aquaculture

Animal feed

Medicine

Although mangroves are very useful to man they are fast disappearing. Major threats:

-Destructive activities of fishermen.

-Some large scale development projects-Aquaculture and building

construction projects

References

http://www.ramsar.org/wn/w.n.srilanka_maduganga.htm(2008.05.22)

http://servesrilanka.blogspot.com/2005/04/mangrove-conservation.html(2008.05.22)

Pinto,Leonard,Mangroves of SriLanka,(1995)

THE END