Strategies for the improved management of coastal zone of Sri Lanka

Abstract

Sri Lanka has a fully operative Coastal lone Management Plan (ClMP), which is periodically updated. The 2003 Coastal lone Management Plan has followed and built upon the 1997 Coastal lone Management Plan with additional components introduced to address the current requirements. However, some areas have not been addressed in great detail even in ClMP 2003. The Costal Erosion Management Plan does not include green engineering measures and the Conservation Plan does not include the Estuary and Lagoon management in depth .It has been emphasized that a national recommendation regarding policy design is inappropriate and site specific policy design is required. Fisheries concerns, which were not addressed earlier, are included in ClMP 2003. Extending the SAM process. to all areas requiring site specific and integrated sustainable resource management are key objectives in the ClMP 2003. Sea level rise is one of the more certain responses to global warming and presents a major challenge to human kind. The average global sea level rise estimated by IPCC is at 31 em to II0cm by the year 2100 with a best estimate of 66cm. The land loss estimated using the simple drowning concept on the southwest coast is 6.0 to 11.5 km2 when the low and high scenarios of sea level rise are concerned respectively. In assessing the vulnerability to sea level rise the new techniques such as GIS, Remote Sensing and Aerial Video Tape assisted analysis should be used. Brunn Rule is another very widely used technique to assess the land loss. It has been estimated that the Coastline of Sri Lanka will recede by as much as 50 to 500mwithin the next century purely due to rise in sea level. Therefore, it is extremely important to pay attention to sea level rise in the future in the design, planning and implementation stages of coastal development, coastal protection and coastal management activities. The estuary management plans should be consistent with the tenets of total catchment management and ecologically sustainable development. It is important to realize that basic methods to understand the distribution of pollutants in estuaries can be a management tool and an aid in decision-making but nothing more. The recommended ratios of nutrients in estuaries are given by Redfield Ratios, however, a review of the literature indicates that optimum N: P ratio can vary between seven and eighty-seven. The greatest uncertainty with estuary nitrogen budgets concerns the contribution of atmospheric deposition. The principal management objective identified for Sri Lanka is conserving lagoons and estuaries to sustain and enhance environmental functions of and promote socio-economic activities connected with them. Three budgets were created for Negombo estuarine system using CABARET. The one layer I box budget indicates that the system is net heterotrophic and denitrification is dominant. The 2 box I layer budget indicates that the estuary is net heterotrophic in the wet season. In the dry season the system box I is net autotrophic while system box 2 is net heterotrophic. In 2 box I layer system too denitrification is dominant in the estuary both in wet and dry seasons. In the 3 box 1 layer model there are some regions in the estuary, which are autotrophic while rest of the regions, are heterotrophic. And in some region nitrogen fixation is the dominant process. Therefore, it is more suitable to use a multiple box model to understand the nutrient pollution problems and biogeochemical processes in the estuary. From the types of management programmes, which have been adopted globally, the use of an effective Integrated Coastal Zone Management Framework is most relevant to the management of Coastal zone of Sri Lanka. When compared to applications of management frameworks from different countries, legal, institutional and organizational requirements are not a serious problem in Sri Lanka. Community based approach which is already in use should be extended and management tools such as GIS and Vulnerability Assessments should be incorporated into the ICMF.