Coastal dune stability: The effect of meteorological conditions and vegetation

Quantitative investigations and research conducted along the north coast of New South Wales, Australia are evaluated with respect to coastal processes, coastal alignment, meteorological data, dune dimensions, dune vegetative cover, development on the dunal area and dune management.The data available covered an assessment of the extent of dune instabilities, an assessment of long term coastline movements, a study of the effect of a cyclone and storm surge, and an assessment and evaluation of a phase of extreme coastline erosion. Specific situations are described and evaluated within the above context. The evaluations are used to determine the extent of coastal dune areas required to be designated as buffer zone in land use planning. The extent of the zone required is dependent upon expected magnitude of wave erosion. Magnitude of wave erosion was found to be proportional to the interaction of coastal processes during periods of extreme erosive factors and the beach dune characteristics for the particular section of coastline. It was found that man's influence on this natural interaction can be a dominating factor in determining beach dune characteristics and therefore the magnitude of wave erosion. — management of the beach dunal area to maintain an acceptable dynamic equilibrium of the beach dune line by a vegetated sand dune of specific dimensions is possible despite weather conditions, if a designated buffer zone is maintained.Presented at the Seventh International Biometeorological Congress, 17–23 August 1975, College Park, Maryland, USA.