small washover fan was formed on the salt marsh to the lee of the tlsuset 

 Spit-Eastham dune line; marsh vegetation did not recover from burial. Three 

 years later, small dunes (75 centimeters high) had formed in the proximity 

 of drift lines. 



While the revegetation process on washover fans has not previously been 

 studied, colonization of the beach-backshore has been the subject of several 

 studies. Since the beach-backshore is an unstable area, the species assem- 

 blage has not been regarded as a defined community. In many studies of 

 community succession in the coastal zone, however, the beach-backshore has 

 been included as the earliest, least developed sere (Gimingham, Gemmet, and 

 Greig-Smith, 1948; Vose, Powell, and Spence, 1957; Laing, 1958; Olson, 1958; 

 Willis, et al., 1959; Morton, 1974; van der Valk, 197A; Ranwell, 1975; 

 Chapman, 1976). 



The importance of drift lines in the initiation of dune-building proc- 

 esses was recognized historically (Cowles, 1899) and has since been repeat- 

 edly stressed (Gimingham, Gemmet, and Greig-Smith, 1948; Robertson and 

 Gimingham, 1951; Salisbury, 1952; Laing, 1958; Olson, 1958; Tansley, 1968; 

 Kanwell, 1975; Chapman, 1976). The characteristic, linear form of barrier 

 dune ridges at a spit terminus has been attributed to the form of drift 

 lines (Godfrey, 1977). 



Details concerning the ecology of the beach-backshore have been numer- 

 ous, but sketchy. Many studies have considered the area without focusing on 

 organic debris; others have examined drift-line debris without considering 

 its role in the overall community development of barrier beaches, Species 

 lists have been made for east (Harshberger , 1916) and west coast (Barbour, 

 DeJong, and Johnson, 1976) beaches in the u lited States. Extensive data 

 are also available in Britain (Gimingham, 1964; Tansley, 1968). 



There ate three ways in which barren washover s can be colonized: 



(1) plants on the previous surface can grow through the washover deposits; 



(2) remnant, or peripheral, vegetated areas can expand into barren deposits 

 by rhizome extension; or (3) new propagules (both seeds and plant fragments) 

 can become established in an area. Colonization of washover fans by the 

 latter two means should be considered primary succession because sand depo- 

 sition is generally so great that the original substrate only tangentially 

 affects vegetation. 



b. Recovery . On Nauset Spit-Eastham, four major dune species were able 

 to recover from high levels (up to 67 centimeters) of overwash burial. 

 Dunes, however, are generally eroded by stomas to depths below the vegetated 

 surface. Plants in site 1 throat and the 1972 washover in site 1 fan ware 

 completely eroded during the February storm. At site 3, two-thirds of the 

 dunes were subjected to erosion; remaining dune plants, however, recovered 

 to biomass levels equal to or in excess of prestorm levels. 



In the salt marsh, deposition occurred without erosion. Both principal 

 marsh species, Spavtina patens and Spavtina altemiflova, were able to 

 recover from low-level burial. Plants at sites 2 and 3, however, were bur- 

 ied by greater volumes of sand; only plants at site 1 were able to recover. 

 Approximately 20 percent of site 1 was populated in 1978 by marsh grasses 

 recovering from overwash. Much of the remaining area was either burled 

 by depths in excess of 33 centimeters (taaximuss recovery depth of Spavtina 

 patens) or had not been vegetated by either species in 1977 . 



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