Derived per-cent measurements

% Constancy[pmp1]  (%C) is a measurement based on the species presence data expressed as the per cent of times a given species is found in the sites visited as a function of all the sites assessed in the study.

 % Basal Area (%BA) for any given species was calculated from the Basal Area values of each species as a function of the total basal area measured at each site.

 A % Encounter [pmp2] (%EBA) value was calculated in a similar fashion as the % Constancy value but using only the presence of a given species if it contributed to the basal area measurement.

 % Stem density (%DS) was calculated for each site for each DBH range (See Table 1), as well as, for the combination of ranges covering breast height diameters above 10cm (%D-p poles excluded).

 % Relative Cover (%Cover) was estimated from the relative contribution that trees, with heights over 15m (height class 3 and up), would have contributed to the basal area of the site based on the following calculation: Height Class x Basal area x % Encounter.

 [pmp1]Constancy: the dispersion of of a species throughout a community. A constant is a species that shows up in almost every sample taken (indicating an occupation of roughly 80%).


4(Ecology) the frequency of occurrence of a particular species in sample plots from a plant community

 [pmp2]Final review: use % Constancy for total frequency and % encounter for BA based values

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