Comparisons of recovered quadrats to quadrats that failed to recover 

 (using site 1 quadrats that were buried by less than 34 centimeters of sand) 

 showed that burial recovery for Spavtina patens is related to burial depth, 

 initial (preoverwash) elevation, final (postoverwash) elevation, initial cover 

 and density of Spavtina patens, and initial and final cover and density of 

 Spavtina altevniflova present in the same quadrats (Figs. 56 to 64). Using 

 all quadrats with Spavtina. patens that received less than 34 centimeters of 

 burial, it was found that there was a negative linear correlation between 

 burial recovery (measured by 1978 cover or density for Spavtina patens) and 

 burial depth (density, P < 0.05, r = 0.180; cover, P < 0.01, r = 0.217). 

 Initial cover (1977), however, is not linearly related to final cover (1978), 

 nor is there a correlation between initial and final density. In 1977 the 

 magnitude of Spavtina patens cover and density was highly correlated with 

 elevation, bur l u l 7 /8 no such correlation was found. General elevation data 

 for quaarats containing Spavtina patens in 1977 and 1978 appear in Figure 

 65. For both 1977 and 1978, cover and density data for Spavtina patens were 

 highly correlated (1977, r = 0.868, P < 0.01; 1978, r = 0.382, P < 0.01). A 

 comparison of the two regression lines using a t-test showed that the slopes 

 are significantly different (P < 0.01). Multiple regression was used in an 

 attempt to develop a model for Spavtina patens recovery based on data 

 collected in 1977 and 1978. Recovery is related linearly only to burial 

 depth when data for quadrats receiving less than 34 centimeters of sand are 

 considered. Elevation (both initial and final) , initial cover, and density of 

 Spavtina altevniflova do not improve a predictive model for Spavtina patens 

 recovery from overwash burial. 



Initial cover volue (pet) 



recover rroo 

 i » 40.4 pet 



over ./at... 

 (83 cases) 



Recovered from 01 

 x <■ 80.5 pet (83 



erwash burial, 

 cases) 



Kruskal-Uallis test results: The rank mean 

 tor quadrats In which plants did not recover 

 from burial does differ significantly from 

 the rank mean for quadrats in which plants 

 did recover (P < 0.01) . 



Figure 56. 



Comparisons of initial cover values for quadrats of Spavtina 

 patens that recovered and failed to recover from overwash burial. 



Figure 



Failed to recover from overwash 

 burial, x - 525 plants (83 cases) 



P~"l Recovered from overwash burial. 

 L*3 x - 941 plants (83 cases) 



460-B99 900-lS«» .M0-I799 >I800 



density (No. of oses per quadrat) 



Kruskal-Wallls test results: The rank mean 

 for quadrats in which plants did not recover 

 from burial does differ significantly from 

 the rank mean for quadrats in which plants 

 did recover (P < 0.01). 



Comparisons of initial density values for quadrats of Spavtina 

 patens that recovered and failed to recover from overwash burial. 



107 



/ 



