Salt water wetlands

Consisting mainly of four groups and fourteen types. Most of these are located along the coastal belt. The only exception is the set of salt water bearing Villus in Wilpattu.

SALT WATER WETLANDS

MARINE	ESTUARINE	LACUSTRINE	PALUSTRINE
Shallow marine waters	Estuaries	Saline / brackish lakes (inland Villius)	Permanent saline / brackish marshes
Marine beds	Tidal mudflats	Seasonal / intermittent saline lakes	Seasonal saline marshes
Coral reefs	Salt marshes	Lagoons
Rocky Shores	Mangroves
Sand / shingle shores

SALT WATER/ BRACKISH WETLANDS
Some of the major types are described below:-

Estuaries and Mangroves:

These are inter-connected coastal wetland types. Estuaries are formed in places where rivers enter the sea. The daily tidal fluctuation and the intermediate salinity between salt and freshwater (commonly termed "brackish water") are main characteristics of this ecosystem. There are about 45 estuaries in Sri Lanka. The mangroves comprise very diverse plant communities that are adapted to grow in unstable conditions of estuarine habitat. The mangroves are a rapidly diminishing wetland type in Sri Lanka, consisting of less than 10,000 ha of discontinuously distributed patches along the coastline. Typical example of estuaries with mangrove wetlands in Sri Lanka includes Maduganga estuary, Bentota estuary and Kalaoya estuary. The latter is the largest mangrove in Sri Lanka.

Lagoons:

These are salt or brackish water coastal wetlands separated from the sea by a low sand bank with one or more relatively narrow permanent or seasonal outlets to the sea. These can also harbour other coastal wetland types such as mangroves, mud flats and sea grass beds. About 42 lagoons are found around the coast in Sri Lanka. Examples include the Bundala Lagoon, Mundel Lake, and Kalametiya Lagoon

Coral reefs and Sea grass beds:

These are two important sub-tidal marine wetlands (below 6 m in depth) in Sri Lanka. Coral reefs consist of calcareous structures secreted by a group of marine invertebrates. Coral reefs are famous for their spectacular beauty. The rich biological diversity of coral reefs could be compared to that of a tropical rainforest. Extensive coral reef habitats can be found in the Gulf of Mannar region, Trincomalee to Kalmunai in the east coast and in several areas of the south and south-western coast, including Rumassala and Hikkaduwa Sea grass beds are composed of rooted, seed bearing marine plants. These are found in shallow, sheltered marine waters, as well as in lagoons and estuaries. Most extensive sea grass beds are present in the northwest coastal waters of Sri Lanka (eg. Kalpitiya to Mannar).

Inland Salt Villus:

Salt water containing Villus within the Wilpattu National Park is a unique ecosystem, which appears as shallow lakes (referred to as 'vila') in sandy soils.