The biodiversity of arthropods from Australian rainforest canopies: General introduction, methods, sites and ordinal results

Abstract

Abstract The arthropod assemblages occurring in the canopies of tropical, subtropical and cool temperate sites have been sampled using a pyrethrum knockdown technique. Details of the techniques used and the climate and vegetation of the areas studied are presented together with an analysis of the distribution of individual arthropods across Orders. An approach using generalized linear modelling partitioned the variance in numbers among sites within forest types and across the three forest types. The effects of both these components were significant. The differences between the ordinal signatures of each forest type are discussed and a number of hypotheses proposed to account for these differences, based on knowledge of the biology of the groups concerned. For the tropical and subtropical sites a comparison was made between samples collected in the low to mid‐canopy with ones collected in the high canopy. Numbers of both insects and non‐insects collected differed significantly with height in the subtropical forest and the distribution of insects across Orders was also significantly different in this forest type. In the tropical forests numbers of insects differed significantly between the two strata but neither the numbers of non‐insects nor the ordinal profiles of either insects or non‐insects were shown to be significantly different.