MARINE AND COASTAL ECOSYSTEMS
An ecosystem is an organized group of organisms living at a particular place and time, interacting with one another as well as with their environment. Malaysia's seas and coasts contain a number of distinct and globally significant ecosystems. Of these, the zones of mangroves and coral reefs are the most important.
Mangroves and coral reefs are the signature systems of Malaysia's marine environment. They not only harbour a great range and number of species, but also act as nursery areas for many vital fish and mollusc species. They are economically important as they support, through being nursery and feeding grounds, a large percentage of the commercial fish caught in Malaysia. Both ecosystems have been, and continue to be, under great pressure from modern development and fishing methods. Mangroves, which line estuaries and sheltered stretches of coastline, are a key Malaysian ecosystem, also providing breeding and nursery grounds for fish and prawns. Today, they make up around 2 per cent of the country's land area. Aquaculture and other coastal developments have taken their toll on the country's stretches of mangrove, with half of their extent having been lost in recent decades. Encouragingly, recognition of the importance of mangroves is increasing, and much of what is left stands a better chance of being safeguarded. In areas such as the Matang mangrove in Perak, sound sustainable forest management is being practised to promote the well-being of this ecosystem. Corals grow best in clear waters and thus the country's coral reef communities are mainly found off the east coast of Peninsular Malaysia and Sabah where the waters of the South China Sea are clear. Although there is one oceanic reef system off the coast of Sabah, the majority of the country's reefs are fringing reefs, lying in the shallow waters just off the beach. Fish, crustaceans and nudibranches all live in and off these reefs, contributing to their amazing biodiversity.
Estuaries, with their importance to human and bird communities, among others, are a key feature of Malaysia's coastline, particularly on the west coast of Peninsular Malaysia. Sand and mud flats, a distinct enough ecosystem to be considered separately, are also found in some estuaries. Here huge communities of molluscs and worms congregate, providing, among other uses, great feeding grounds for birds. Associated with the estauries, there are many areas of mud flats along the west coast of the Peninsula.
Sandy beaches and rocky shores are two other ecosystems found in Malaysia, particularly on the east coast of the Peninsula. Here the environment changes daily, from one extreme to the other, submerging and exposing the ecosystems at least once, sometimes twice, a day. Besides supporting a variety of organisms, including an array of crustaceans and molluscs, which have adapted to the harsh environment, sandy beaches and rocky shores act as natural breakwaters, thus playing a vital role in protecting the hinterland.