GENETIC AND ECOLOGICAL VARIATION IN ATHEROSPERMA-MOSCHATUM AND THE IMPLICATIONS FOR CONSERVATION OF ITS BIODIVERSITY

Population genetics and ecology of Atherosperma moschatum Labill. (sas safras), a major canopy tree of Australian temperate rainforests, were examined and used to identify priorities and strategies for conservat ion of its genetic diversity. The genetic diversity among populations was fairly low, but higher than average for long-lived late succession al or wind dispersed species (Hamrick and Godt 1989). Genetic distance s between populations were correlated with geographic distances and cl imatic differences. The major genetic differentiation was between the mainland populations and those in Tasmania, with the New South Wales p opulations being quite genetically distinct. Most genetic variation wa s found within populations, however, most populations were inbred. Thi s is likely to be due to selfing and spatial genetic substructure resu lting from vegetative spread and local dispersal. There was evidence o f regeneration in all populations, however no consistent regeneration patterns emerged. Population density was inexplicably correlated with genetic distance. There was as much diversity in all variables (ecolog ical and genetic) measured in small isolated populations as there was in stands within larger assemblages; therefore, population size does n ot appear to be a major factor affecting viability. Genetic variation was spread throughout the distribution of A. moschatum. Therefore, pop ulations from throughout its range would need to be conserved to retai n the genetic diversity within this species.