An objective classification of Ontario plateau alvars in the northern portion of the Mixedwood Plains Ecozone and a consideration of protection frameworks

Abstract

To develop an alvar classification system based on grouping criteria generated by data analysis and to apply the system in an evaluation of existing protection frameworks, species lists for 57 Ontario alvars were used to analyze the relationship between sites based on a UPGMA clustering of Jaccard's coefficients. A principal coordinate analysis was used to complimentarily reduce the dimensionality of the data, and this analysis also provided the coordinate axes used to assess available protection frameworks. The sites were classified into nine groups including three major groups and their subgroups: (1) the Smiths Falls, Napanee, and Carden plains all of which were quite distinct, (2) the Bend Bay and Trent River sites which are predominantly alvar savannas lacking some of the characteristic open alvar communities such as pavements, and (3) the Bruce Peninsula and Manitoulin Island region which may be divided into three major subgroups. The floristic basis for the classification is outlined. In the absence of biological data, a geographic framework proved to be the most useful. Classification of sites based on physiographic and climatic regions also proved useful, but the results suggested that strict adherance to arbitrary divisions not supported by analyzed data could lead to substantial gaps within a system of representative protected sites.