Multivariate Relationships between Floristic Composition and Stand Structure in Vegetation of Ku-ring-gai Chase National Park, New South Wales

Abstract

The relationships between stand structure and floristic composition were examined from data collected from 100 quadrats on two soil types: Hawkesbury sandstone and Narrabeen group soils, occurring within Ku-ring-gai Chase National Park, New South Wales. Floristic composition was determined using the frequency of species occurring within nine concentric sub-quadrats of total area 500 m². Stand structure was determined by a multivariate classification scheme utilising the foliage projective cover of eight strata within each quadrat. The patterns in floristic composition and stand structure were examined through multivariate analyses. Procrustes analysis of non-metric multidimensional scaling ordinations of both the stand structure and composition data showed floristic composition gradients to be well recovered by the structure data. Similar gradients were evident in both vegetation attributes, between and within the two soil types, with the rank order of community types across the ordinations being the same. However, some important differences were evident between the ordinations of floristic composition and stand structure between and within soil types. A number of floristically dissimilar communities exhibited very similar multivariate structural characteristics. In particular, two floristically distinct communities on different soil types were indistinguishable in terms of their structural characteristics. The multivariate analyses suggest a possible convergence of some compositionally distinct communities towards a common structural formation.