Bushland sites in the northern suburbs of Sydney were compared to sites in Brisbane Waters National Park, Ku-ring-gai Chase National Park and Royal National Park which are relatively unaffected by suburban development. Both shale-derived and sandstone-derived soil infour physiographical locations were examined, with three replicates of each of the 16 combinations.Phosphorus levels are higher in the soils of suburban sites compared to soils derived from similar rock bases in non-suburban sites. Phosphorus levels are also higher on shale-derived than on sandstonederived soils, and lower on hilltops than in other physiographic positions. Suburban sandstone sites have soil phosphorus levels similar to those of nonsuburban shale sites.Three major and three minor clusters of species were distinguished using a hierarchical agglomerative clustering. The major clusters consisted of (1) species commonly associated with wet sclerophyll forests and rainforest margins, (2) species directly or indirectly related to the presence of man, and (3) species associated with dry sclerophyll forests and heaths.Using analyses of variance and covariance, arui logit models, the abundance of the first main cluster was related to nutrient-rich soils and the abundance of the third main cluster to low nutrient soils whereas the presence of the second main cluster was almost entirely restricted to sites surrounded by suburbs.The development of suburbs around vegetation patches has led to an increase in the abundance of native and exotic mesomorphic species and the Present address: Macleay Building.

The current study demonstrated that Themeda australis (R. Br.) Stapf (kangaroo grass), a major understory component of the original grassy Box woodlands in the Central Tablelands of New South Wales, was suitable for use in large-scale mine rehabilitation. The results of the trial were applied in the mine rehabilitation program. Due to extensive clearing of the woodlands and the introduction of exotic flora and fauna for agriculture, only small remnants of the original flora remain. The final land use of the gold mine is a conservation area free from agricultural pressure. Local native species adapted to the soil conditions and variable climate are highly desirable for the control of soil erosion following mining. Germination and establishment of T. australis on oxidized overburden were examined over 53 weeks. Seedbearing mulch was used as both the seeding material and an organic additive to the overburden. The effects of five factors were investigated: time since soil preparation, position within small contour banks, location of contour on experimental slopes, additional water, and rate of seed/mulch application. Direct seeding using the lowest rate of mulch application resulted in the establishment of more T. australis seedlings on new contours than on 15-month-old contours. The provision of additional water increased germination and establishment in both old and new contours, but was not essential. Seedling densities were greatest in the middle positions of contour banks up to week seven, but were destroyed during a heavy storm. At the close of the experiment, seedling densities were greater in the top and bottom positions of contours. Although significant slope ϫ rate and age ϫ slope interactions occurred, SNK tests did not reveal any consistent interpretable results.

In this note we demonstrate that the Buckney and Morrison (1992) data subsets are located on different geomorphological units and different pre-mining plant communities with different fire histories. The conclusions that they have drawn from their data are therefore not valid.

The characterization of late Holocene climates in northern Australia has, in the past, been based on local investigations. This examination of the chenier record of northern Australia indicates that there has been a statistically significant regional change in conditions between 1600–2800 years bp, possibly a period of relative aridity. Support for this conclusion may be found in the vegetation record from the Atherton Tableland where numerical comparisons of dryland fossil and modern pollen spectra suggest that rainfall may have been up to 50% higher during the period 7000 to 3000 bp.

The protection of whole assemblages of species requires that such assemblages be identified in some nonarbitrary, quantitative manner. Clustering methods can be used to identify groups or clusters of observations (i.e., sites, transects, quadrats, etc.) on the basis of multivariate assemblage data, where each species is a variable. There are many kinds of cluster analyses, all potentially providing different outcomes, that is, different clusters of the multivariate observations. The wide choice of clustering methods and the necessarily subjective choice of which method and measure of similarity to use for a particular data set is problematic. It can lead (and has led) to disputes about the way multivariate observations should be grouped, causing conflicts in making environmental decisions. We present a statistical test for choosing among competing cluster models and demonstrate its use with a case in point. The method provides an objective way to discriminate among competing models in order to determine the model that best fits the available data. Provided each party in a dispute identifies and articulates the cluster model it supports, the method can give a nonarbitrary judgment concerning the best model. This method provides an important tool for the resolution of environmental disputes concerning the presence of a particular community at a particular place and time, which may be impacted by a proposed development.