Region Of South-eastern Australia Research Articles

THE USE OF GENETIC MARKERS TO DEMONSTRATE THE ABILITY OF FIELD POPULATIONS OF LUCILIA CUPRINA DORSALIS R.‐D. (DIPTERA: CALLIPHORIDAE) TO OVERWINTER IN SOUTH EASTERN AUSTRALIA.

AbstractA technique involving the genetic labelling of field populations of Lucilia cuprina dorsalis R.‐D. has been used to demonstrate the ability of this pest to overwinter in subalpine regions of south eastern Australia. The implications of this finding on the choice of strategies for genetic control of this pest are discussed.

Definition of rainfall regions of south-eastern Australia by numerical classification methods

The aim of the study is to define homogeneous rainfall regions in order to improve methods for meso-scale extrapolation of isohyets. Two multivariate approaches are used, agglomerative classification and a modification of principal coordinates analysis. The median, mean, upper and lower quartiles and deciles for each month for a 30-year period were used as the attributes for 109 rainfall stations. Several data standardizations and classification methods are examined. Classification results were robust with respect to changes of method. Standardization based on proportions was preferred to that based on standard deviates. Fourteen groups of rainfall stations are recognized arranged in four regions. Use of mean data for groups clearly shows the spatial pattern of seasonal changes in rainfall. Differences in the relationship of rainfall to altitude are shown to be marked between geographically adjacent groups of rainfall stations.

Studies of field populations of rhizobium: Effectiveness of strains of rhizobium trifolii associated with trifolium subterraneum L. pastures in South-Eastern Australia

Field populations of Rhizobiuin trifollii from eight regions in south-eastern Australia were sampled over a period of 5 years from 1966 to 1970. The R. trifolii isolates were tested under bacteriologically-and environmentally-controlled conditions for effectiveness of nitrogen fixation in combination with Trifalium subterraneum L. cv. Bacchus Marsh; the effective strain TA1 was used as a standard of comparison. Mean effectiveness of the R. trifolii populations for any region at any sampling varied between 62 and 93 percent of the effectiveness of the standard strain. The principal feature was the large variability within sampling sites, between sites within paddocks, and between paddocks within regions. In addition there was some variability with time in the range of effectiveness values of isolates within a site and in the absolute values for both sites and paddocks. Effectiveness values were not related to soil pH, size of population of R. trifolii, inoculation procedure at sowing, age of pasture, annual rate of fertilizer application, or mean annual rainfall.

Palaeomagnetism and the tectonic evolution of the Tasman Orogenic Zone

Abstract Palaeomagnetic data obtained from studies of rock formations in southeastern Australia are compared with data from the main Australian assemblage. Occurrences and distributions of some of the major serpentine and ultramafic belts in the Tasman Orogenic Zone are interpreted according to current plate theory as marking sites of ancient plate margins. A tectonic model based on the palaeomagnetic data with the aid of geological constraints is proposed. It describes the rotation of a small region in southeastern Australia, relative to the main assemblage, by about 90° since the Middle Silurian and 30° since the Early Devonian. The proposed small plate boundaries may be represented by the Great Serpentine Belt to the east and in part by the less well defined belt of serpentinites which outcrop from Kiandra to Nyngan on the western margin. It seems unlikely that the whole of the western serpentine belt was actively involved with accretion during the Siluro‐Devonian. The northern limit of the plate canno...