The Application of Association-Analysis to Phytosociology

Abstract

Association-analyses of phytosociological data from salt-marshes, fens and woodland in the Burren, Co. Clare, Ireland, are considered in relation to a traditional phytosociological treatment. ft is concluded that association-analysis is of value in examining the consistency of evidence and conclusions in phytosociology and in detecting directions of variation overlooked by traditional methods, and that it provides a powerful tool for the detection of faithful and differential species. Some properties and limitations of association-analysis are discussed. In view of certain criticisms of nodal analysis, it is suggested that the two-way table is the most useful presentation of the data for phytosociological work, especially when the aim is a general classification of vegetation rather than a specific ecological examination of a single site. Sample-size and distribution, and the relation of association-analysis to ordination methods are briefly discussed.