Coastal Zone

The coastal zone constitutes 8 percent of the global ocean surface. Most scientific definitions of coastal zones are based on coastal processes or landform. The International Geosphere–Biosphere Program defines a coastal zone as “extending from the coastal plains to the outer edge of the continental shelves, approximately matching the region that has been alternately flooded and exposed during the sea level fluctuations of the late Quaternary period.” This space includes the foreshore, the beach area and natural coastal protection systems such as sand dunes and mangroves.

While the coastal zone can be divided into many types, Inman and Nordstrom devised a classification system for coasts based on plate tectonics, dividing the coastal zone into collision coasts, trailing edge coasts and marginal sea coasts. Other coastal zone types include hard rock-cliffed coasts, hard rock coastal plains, soft rock coasts, tide-dominated sediments, plains, and wave-dominated sediment.

Many natural processes influence the integrity and environment of the coastal zone. For example, the lithosphere—which incorporates plate tectonic settings, bedrock geology, coastal topography, and sediments—affect the structure and form of the coastal zone. The coastal zone is also affected by processes within the hydrosphere, which includes all marine processes such as waves, tides, ocean currents, regional currents, sea temperature and sea-level change; the atmosphere, including climate change, annual climate, precipitation, temperature, wind; and the biosphere, which includes all coastal flora and fauna.

Scientific definitions of the coastal zone are not always appropriate for the purposes of management. Definitions located within policy frameworks often differ from scientific interpretations. For example, the Commonwealth of Australia's Coastal Policy states that the “the boundaries of the coastal zone extend as far inland and as far seaward as necessary to achieve the policy objectives, with a primary focus on the land/sea interface.” In Canada, the definition of the coastal zone is “the coast itself, coastal watersheds and the lower limits of large drainage basins, and the area seaward to the limit of the zone of influence of land-based activities.” Coastal managers in Canada are advised that the definition should be interpreted flexibly to ensure that all activities and issues having a bearing on the planning area are addressed. The Organization for Economic Cooperation and Development argues that the definition of the coastal zone should vary depending on the nature of the problem being examined and objectives for its management.

Many nations across the world have implemented an integrated coastal area management (ICAM) process to manage the many uses and activities along and within the coastal zone. The United Nations (U.N.) Educational, Scientific and Cultural Organization (UNESCO) define ICAM as an interdisciplinary activity where natural and social scientists, coastal managers, and policy makers, focus on how to manage the diverse problems of coastal [Page 292]areas in the long term. The U.N. Environment Program has identified key principles for integrated coastal zone management, including: the coastal area is a unique resource system that requires special management and planning approaches; water is the major integrating force in coastal resource systems; coastal management boundaries should be issue-based and adaptive, be protected from damage from natural hazards and conservation of natural resources should be combined with integrated coastal zone management programs; that all levels of government within a country must be involved in coastal management and planning; and that conservation for sustainable use should be a major goal of coastal resources management.

...