Development of a coastal vulnerability index: a geomorphological perspective

Sustainable coastal resource management requires the safeguarding and trans mission to future generations of a level and quality of natural resources t hat will provide an ongoing yield of economic and environmental services. A ll maritime nations are approaching this goal with different issues in mind . The UK, which has a long history of development and flood protection in c oastal areas, has chosen to adopt shoreline management, rather than coastal management, so placing coastal defence above all else as its primary and s tatutory objective. This paper aims to provide a geomorphological perspecti ve of long-term coastal evolution and seeks to compare the UK approach with wider interpretations of coastal management. Based on a literature review, it is argued that coastal management (CM) and shoreline management, as a s ubset of CM, should share the same ultimate objectives, which are defined b y many authorities as sustainable use. The objectives, both strategic and p ragmatic, which follow from such an aim may appear to conflict with a readi ng of many of the texts for international and national CM or designated are a management which emphasizes stability rather than sustainability. The res ult is that coastal defence is seen not merely as a means to an end but as an end in itself. It is argued within this paper that sustainable use of th e coast, however, demands both spatial and temporal flexibility of its comp onent systems, and management for change must therefore be the primary obje ctive. Response of the natural system to independent forcing factors must b e encouraged under this objective, whether such forces are natural or anthr opogenic. In achieving such an objective the concept of shoreline vulnerabi lity may prove useful. A simple and preliminary Vulnerability Index is prop osed, relating disturbance event frequency to relaxation time (the time tak en for the coastal feature to recover its form). This index provides a firs t order approximation of the temporal variability that may be expected in l andform components of the shoreline system, so allowing management to provi de more realistic objectives for long-term sustainability in response to bo th natural and artificial forces.