a ' Overwash and Aeolian Processes . Hiring several storms which resulted 

 in overwash, measurements were taken of surge duration, velocity, flow depth, 

 and bed scour. These data have important ecological implications since flow 

 velocity and turbulence determine whether an overwash surge is depositional or 

 erosional. From these measurements and from field surveys, the impact of an 

 individual storm of a particular size on the barrier can be assessed. This 

 information can also be used to determine the minimum distance from the berm 

 crest for beach grass restabilizatlon. 



Elevation transects were surveyed before and after major storms to docu- 

 ment the rate of beach and dune erosion and quantify the volume of sediment 

 carried by overwash to the back barrier. As the resulting washovers deflated, 

 elevation surveys were continued to determine the amount of sediment loss from 

 these deposits. Sand lost from the barrier by wind deflation and trapped in 

 vegetated dunes as a result of washovers was also measured. 



b. Vegetat ive Response to Overwash . Vegetation at three sites on Nauset 

 Spit was extensively sampled in YWTl before the major northeaster in February 

 1978. All three sites were buried by overwash sand during this storm and 

 were resampled during the following two summers. Examples of ail major plant 

 communities on the Nauset Spit system are included in these data to assess the 

 response of coastal vegetation to overwash burial. 



During major overwashes large volumes of sand are deposited on salt 

 marshes, killing plants. Following the ±978 northeaster, barren washovers 

 covered large areas of the Nauset Spit system. The means and rate of revege- 

 tation of these washovers have been studied, using the vegetation sampling 

 sites surveyed before the storm, with particular attention focused on the role 

 of drift lines in the revegetation and in the development of new dunes. 



c. Barrier Evolution . Shallow cores (up to 3 meters long) were used to 

 determine the lateral and vertical extent of washover deposits and to provide 

 information on the geologic rate and means of landward barrier migration. 

 Maps, charts, and accounts dating back to the early 1600's were consulted to 

 reconstruct historical shoreline changes. U.S. Coast Survey maps (1851, 1856, 

 1868, 1886) and vertical aerial photographs (1938 to 1978) were used to map 

 shoreline changes and physiographic feature?. The distribution of washovers 

 along the spit system was mapped from aerial imagery and located in the field. 

 This information can be used to determine the rate of change in vegetation on 

 washovers and on more stable parts of the barrier. 



Vegetative-physiographic transects at 15 locations along the Nauset Spit 

 system were established to document plant community development on washovers. 

 These transects were also used to delineate topographic and plant species 

 changes associated with the formation and stabilization of foredunes. The 

 relationship between species composition and physical factors such as salt- 

 spray exposure, saltwater flooding, sand burial, and elevation was delineated 

 by these field studies. 



3. Previous Studies. 



Research on coastal vegetation has focused primarily on community 

 zonation, in relation to environmental factors, and on sand dune and salt- 

 marsh development. Detailed work has been conducted on the effects of salt 



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