SUMMARY 



Along the east coast of the United States, many barrier beaches are 

 undergoing landward retreat as sea level rises. Human development of these 

 barriers has resulted in increasing attempts to control natural orocesses 

 with artificial stabilization. Understanding barrier island processes is an 

 important first step in determining the results of stabilization. This 

 report summarizes research undertaken to provide the scientific data neces- 

 sary to understand the natural dynamics of a northeast barrier beach system. 



Coastal research to date has focused on either ecological or geological 

 processes; only a few projects have been designed to consider the interaction 

 between vegetation ard the physical factors which shape barrier beaches. 

 This is the first detailed study undertaken to gather and analyze data or. the 

 effect of physical processes, principally overwash, on plant communities and 

 physiographic features of barrier beaches in the Northeast. 



Kauset Spit, Cape Cod, Mass., was chosen for this investigation because 

 overwash has frequently occurred along this retreating shoreline, and histor- 

 ical information is available for almost 400 years. The Nauset Spit system 

 developed from the deposition of material eroded from glacial cliffs and 

 transported southward by littoral currents. This barrier beach system was 

 formed by spit elongation over the past 5,000 to 7,000 years. The spit system 

 has continued to evolve and has migrated landward, constantly reducing the 

 overall dimensions of the enclosed bays. Nauset Spit is dependent on the 

 eroding headland (glacial) section of the outer cape for its continued sedi- 

 ment supply. The Kauset Spit system consists of three major parts: Nauset 

 Spits — Eastham and Orleans, North Beach, and Monomoy Island. 



Methods. Various techniques were used to provide insight into the dy- 

 namics of a northeast barrier beach system. A range of information .collected 

 during different time frames was examined to evaluate the role of overwash and 

 foredune processes in barrier beach dynamics. Overwash processes were de- 

 scribed from field data collected during several minor storms and during a 

 major northeaster in February 197S. The response of vegetation to overwash 

 burial and the colonization of washovers by vegetation were studied using data 

 collected between 1977 and 1979. Transects were established along Nauset Spit 

 to determine the development of plant communities and morphological features 

 on barrier environments that have a well-documented history. Aerial 



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