Development

Direct physical alteration and destruction of native habitats occur in coastal regions through dredging for shipping channels and harbours, the filling of shallow habitats for coastal building, and contamination of water sources. Indirectly, poorly planned urban, industrial and port developments contribute to the destructive effects of land-based sources of pollution to the marine environment through contaminated sediment. Watersheds cleared of their forests and other vegetation covers are vulnerable to erosion and flooding. During high water periods, silt and pollutants within these basins are carried far beyond normal, impacting a greater number and extent of coastal habitats.

Construction of Ports and Backwaters - Coastal engineering studies have revealed that the construction of breakwaters alter the sediment transport mechanism in the coastal areas, thereby causing erosion and accretion. Impacts have been noticed due to construction of port of Chennai, Paradip, etc.  It has been found that due to the establishment of the port of Chennai, an accretion of 75 acres has occurred in the last 60 years south of the port as well as severe erosion in the north resulting in the loss of 83 acres of land. Of the total aggregation, out of 590-km length of coastline, nearly 90% are facing the problem of erosion.

Shipbreaking - A ship's life lasts for an average of 25 to 30 years after which they are no longer considered safe to sail. 95% of these huge ships are made of valuable steel, which makes dismantling them to recover it, a lucrative prospect. But these ships, especially the ones built in and before the 80's, also have tons of extremely toxic substances, hazardous to human and environmental health. During ship-breaking, the major components like engine, etc., are removed and offloaded to the shore. The hull and other steel parts are cut into different sizes and transported as scrap.

At present, the activities related to the breaking of ships have been reported from the coasts of Gujarat (Alang), Maharashtra (Mumbai) and, to a certain extent, off Tamil Nadu (Tuticorin) and Kerala (Azhaikal).  Beaches where ship breaking happens, are now graveyards littered with machinery parts, oil rags and leaking barrels, the air poisoned by open fires, the land and surrounding water contaminated by asbestos, heavy metals, dioxins and other persistent organic pollutants. Increased concentrations of these toxic contaminats in the sea is lethal to the ecosystem causing significant damage to the benthic organisms particularly the filter feeders like clams, mussels, etc.

Tourism - Tourism has contributed to the physical degradation and destruction of coastal habitats across our coast. Aside from the ecological threats that these activities pose to marine habitats, they additionally threaten the socio-economic values associated with the goods and services provided by these habitats. A precautionary approach should be used in any development of tourism and recreation use.

Aquaculture - Aquaculture in the industrial mode poses several threats to our marine and coastal biological diversity and their associated habitats. For example, in many areas in Orissa, Tamlinadu amongst other states conversion of coastal mangrove habitat for production of shrimp is the primary habitat threat. It may pose additional threats through excess nutrients and antibiotics in the  wastes, accidental releases of exotic species or genotypes, transmission of diseases to wild stocks, and displacement of local and indigenous species.