COMPUTATIONS 



V 



1 . Computation of prevalence index (Pi) for transect #1 : 



PI; = 



' ' (fb + ("fw -^ ''f ^ ^u -^ f'u ) 



(1x4) ^ (2x29) -K (3x24) ^ (4x25) ^ _234_ ^ ^ 35 

 ^'1 " 4+29 + 24 + 25 ^^ 



where: 



PI . ^ Prevalence index for transect i 



F ' = Frequence of occurrence of obligate wetland species 



F = Frequency of occurrence of facultative wetland species 



F f = Frequency of occurrence of facultative species 



F,^ = Frequency of occurrence of facultative upland species 



F^ = Frequency of occurrence of upland species 



2. Computation of mean prevalence index (Pl^) <or three transects: 

 Ply 



where: 



PIm = Mean prevalence index for transects 

 Plj = Sum of prevalence index values for all transects 

 N = Total number of transects 



For example: PI for Transect 1 = 2.85 

 PI for Transect 2 = 3.1 6 

 PI for Transect 3 = 2.93 



PI 



2.85 + 3.16 + 2.93 _ a94 ^ ^ 93 

 M " 3 " ~ 3 



D-3 



