ENVIRONMENTAL DEGRADATION DUE TO INLAND CORAL MINING IN AKURALA, SOUTHWESTERN COASTAL ZONE

Abstract

The Akurala coastal stretch (approx. 87-S<) krn from Colombo) provides an excellentexample of environmental degradation due to human exploitation of coastal resources.Holocene corals are found 2.5 - 3.0 In below the surface in a stretch extending about I kminland from the coast. The objectives of the present study were to assess the degree ofenvironmental degradation resulting from JI11andcoral mining in this stretch. 1\ was basedOll a field survey, air photo interpretation and GIS application.

Although inland coral mining in Akurala records a history of over two hundred years, thisactivity has intensified over the past fifty years. The remaining pits vary in size (small: 10-465 rrr', medium: 465-1365 m2 and large: 1365-929Gm2). Mangrove plants and mangroveassociates invade these pits. The commonest are Acrosticum aureum, Bruguiera sexangulaand Lumnitzera racemosa. Among the inangrove associates and non-mangrove species are,Cerbera mangas, Hibiscus tiliaceus, Pandanus sp. Premna servattfolia and several sedgespecies (Cyperaceac). There are also such invasive plants as Annona glabra, Salviniamoles/a. and Panicus maximum growing in and around the pits.

The buried coral beds are a valuable resource providing employment in mining andassociated activities to 45% of the area's population. Yet, coral mining has created manyproblems. The threats of deep pits to people, land subsidence and damages to houses arcthe main problems. Proliferation of invasive plants and mosquito breeding destroy theaesthetic value.

Among the recommendations emanating from the study, the closing of abandoned pits ismost relevant. Also aquaculture in large pits can be viable. Planting mangroves in someparts too can help restore Sri Lanka's dwindling mangroves.