Introduction

Coastal zones are the home of natural features such as beaches, estuaries, lagoons and coral reefs, as well as of human populations and their activities such as port development, commercial fisheries, industries, and tourism. The coastal zone, therefore, is ecologically and economically significant. Port development and dredging activity, for example, can significantly degrade coral reef through the occurrence of sedimentation. Reclamation activity can decrease seagrass and coral cover area through changes on current patterns and sediment transport. Industrial development in the coastal zone can generate pollutants including heavy metals and changes in water circulation and temperature patterns can change the productivity of wetlands. Similarly, the removal of mangrove forests for fish and shrimp ponds in tropical countries affects the functions of mangrove ecosystem. Activities in the further upland such as agriculture, industry, and mining for example, are sources of important pollutants that can affect the functioning of coastal ecosystem through the increased flow of sediments and pollutants into river and estuarine systems. These changes in marine and coastal ecosystem as marine life habitat cause depletion of coastal and marine resources. Increasing development activities and coastal resources management in the coastal zone, particularly in developing countries, have put the natural resources and marine ecosystems in these areas under severe pressure (Burbridge et al ., 1988; Cicin-Sain and Knecht, 1991 ).