Measuring Propagule Pressure
The total probability of establishment (E) can be determined using this equation. It considers the fact that each propagule has an independent chance of establishment:
(E) is the total probability of establishment (p) is the probability of a one propagule establishing (N) is the # of propagules arriving at specific location at a certain time (l) is the location (t) is the time
- It is to be noted that the equation can also be written as the standard asymptotic curve (sometimes termed the independence model):
Alpha=shape coefficient which is equivalent to –ln(l – p).
Measures of propagule pressure are have been shown to have specific relationships with the probability of establishment.(Leung et al. 2004)
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