(b) Comparison 6 . Site l-F-p-77 was affected by overwash in 1972 

 and had recovered from shallow sand deposition by regrowth from below the fan 

 surface or by rhizome extension from the surrounding marsh. Comparisons were 

 made between this recovery area and the adjacent marsh (site l-F-m-77), which 

 was unaffected by overwash, to determine the community response to shallow 

 overwash burial 5 years after overwash (Fig. 29; Tables 5 and 6). Test pits 

 dug in the fan after the 1972 stonn demonstrated that site l-F-m-77 vegetation 

 was similar to the vegetation below the washover fan. Mean elevation for site 

 l-F-p-77 was 17 centimeters higher than the surrounding marsh. Species rich- 

 ness was similar in the two areas (six species at site l-F-p-77 and seven at 

 site l-F-m~77). Only Distichlis epiaata was present on the marsh, but was not 

 found in the peripheral area. 



Other vegetation data from Nauset Spit-Easthara suggest that Salicomia 

 virginica t Pucninellia so., A gropyvon pungans, and Limoniim nashii are not 

 able to recover from substantial burial (greater than 0.10 meter). These 

 species probably colonized the peripheral area after the initial vegetative 

 recovery from overwash burial. Kxuskal-Wallis tests run on all cover and 

 density data demonstrated that in all case* there was a significantly lower 

 value for the peripheral area than the adjacent marsh (P < 0.01). The high 

 similarity index (87.3) indicates that, after 5 years, peripheral areas of a 

 washover fan affected by shallow burial resemble the surrounding marsh areas. 



(c) C omparison 7 . All 234 quadrats sampled at site 3-M-77 were 

 compared with the same quadrats resampled in 1978 to determine the effect 

 of deep overwash burial O0.45 teeter) on a salt-marsh coEmunity (Tables 12 

 and 22). Site 3-M-77 was a well-developed salt marsh in 1977 dominated by 

 Spartina patens (cover » 61 percent) , Salicomia vivginica (cover - 26 per- 

 cent), and Pucainellia sp. (cover - 14 percent). 



Table 22. Surroaary of data collected from 221 quadrat 

 samples at site 3 sarsh. August 1978. 



Specie©' 



Pet t&latlvo Pet P*latl»e Total Relative 





;jrc nana 100. 95.} 



Drift 3 .6 *.: 



'Mverslty - 0.5000; Richness - ». 



-IV. s ate ia.(iurt.»nci- values calculated t rem cover, Ireqiwncy, ami tensity 

 of the plants. 



The entire area was subject to overwash burial (>0.45 cseter) , which 

 exceeded the recovery capacity of all sait-tsarsh plants (Table 22). Mean 

 elevation was increased by 68 centimeters fro® 1977 to 1978 (Fig. 21). Topo- 

 graphic relief was increased between 1977 ( a « 0.08 caster) and 1978 ( o ° 0.19 

 meter). Site 3-M-77 was ettresely fist, reflecting the gradual sedimentation 

 process in salt aarshea (Ranwell, 1959). The February 1973 overwash deposit 

 at site 3-M sloped taarshsard and contained occasional drift piles, which also 

 increased ssicrotopographic differences. 



84 







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