The Preston diagram is a table showing the number of species having
abundances in specified abundance classes. Consider the following
Preston diagram:
(0,1] (1,2] (2,4] (4,8] (8,16] (16, Inf)
number of species 73 33 24 36 39 55This shows that there are 73 species withe abundance 1 (that is,
singletons), 33 species with abundance 2-4, 24 species with abudances
4-8 and so on.
Note that some authors count any species with an abundance on the
boundary between two adjacent abundance classes as being split 50-50
between the classes. This is not done here; note the type of brackets
used in the diagram above that show whether the interval is open or
closed (here, open on the left and closed on the right, apart from the
most abundant class).