in areas receiving shallow burial. However, Spartina alterniflcra was not 

 able to recover from overwash burial in excess of 22 cm. 



Recovery of plant communities following overwash is related to the plant 

 community type and the frequency of overwash events. Dunes have been evident 

 from aerial photography analysis on washovers deposited over salt marshes in 

 as little as 3 years. Salt marshes may develop rapidly; however, marsh 

 development is not as predictable as dune development. In as little as 

 10 years, salt marshes have become visible on aerial photos in areas that had 

 been washovers. Only with shallow deposits at the outer edges of washovers 

 do salt-marsh species recover from burial. These recovering species often do 

 not survive unless overwash activity is reduced in the area. 



Barrier evolution. Many barrier beaches along the east coast of the 

 United States are undergoing landward retreat in response to sea-level rise. 

 Landward displacement can be divided into two separate phenomena: migration 

 of the barrier landforra as a whole, and migration of physiographic features 

 (e.g., sand dunes) on the barrier surface. Barrier migration occurs over 

 long periods of time and is often the result of continuous shoreline erosion 

 with periodic back-barrier extension resulting from inlet activity or over- 

 wash. There are three general me nanisms by which barrier beaches move land- 

 ward: (a) aeolian, (b) overwash, and (c) inlet processes. All three of 

 these mechanisms play a role in the evolution of the Nauset Spit barrier 

 system. 



Wind transport of sediment (aeolian transport) plays only a minor role 

 in the landward migration of Nauset Spit because the net movement of wind- 

 blown sand is in the seaward direction. However, as noted earlier, a portion 

 of the sand deflated from overwash fans is incorporated into the landward 

 margins of the dunes adjacent to the fan. This is one mechanism by which 

 dunes are translocated landward. 



Inlets historically have played a major role in landward sediment 

 transfers along all sectors of the Nauset system and presently in many areas, 

 Nauset Bay is essentially filled with marsh islands constructed on flood- 

 tidal delta deposits. The upper reaches of Pleasant Bay have undergone 

 extensive sedimentation and, hence, shallowing by inlet activity. The 

 earliest records date to 1602 when explorers noted a series of inlets cut 

 through the North Beach barrier. This spit segment has undergone at least 

 three different series of inlet formation with subsequent inlet migration 



