Figure 4. Analysis of Pielou’s J′ index of species evenness (Pielou, 1966) among sampling sites in Montreal (A) and Quebec City (B).

The index indicates how close in number each species is in each sampling site; a value of 1 refers to a completely numerically even community of species, whereas a value closer to 0 indicates a numerically unbalanced community. The results show that, particularly in Montreal, more uneven communities are found in urban cemeteries than in community gardens or city parks.