The two major forms of disturbance in the montane ash eucalypt forests of the Central Highlands of Victoria (southeastern Australia) are clearfell logging and unplanned wildfires. Since the 1930s wildfire has been followed by intensive and extensive salvage-logging operations, which may proceed for many years after a wildfire has occurred. Although applied widely, the potential effects of salvage logging on native flora and fauna have been poorly studied. Our data indicate that the abundance of large trees with hollows is significantly reduced in forests subject to salvage harvesting. This has implications for thepersistence of an array of such cavity-using vertebrates as the endangered arboreal marsupial, Leadbeater's possum (Gymnobelidues leadbeateri). Salvage logging also reduces the prevalence of multiaged montane ash forests--places that typically support the highest diversity of arboreal marsupials and forest birds. Limited research has been conducted on the effects of salvage logging on plants; thus, we constructed hypotheses about potential impacts for further testing based on known responses to clearfell logging and key life history attributes. We predict many species, such as vegetatively resprouting tree ferns, will decline, as they do after clearfelling. We also suggest that seed regenerators, which typically regenerate well after fire or conventional clearfelling, will decline after salvage logging because the stimulation for germination (fire) takes place prior to mechanical disturbance (logging). Understoryplant communities in salvage-logged areas will be dominated by a smaller suite of species, and those that are wind dispersed, have viable soil-stored seed remaining after salvage logging, or have deep rhizomes are likely to be advantaged. We recommend the following improvements to salvage-logging policies that may better incorporate conservation needs in Victorian montane ash forests: (1) exemption of salvage logging from some areas (e.g., old-growth stands and places subject to only partial stand damage); (2) increased retention of biological legacies on burned areas through variations in the intensity of salvage logging; and (3) reduction in the levels of physical disturbance on salvage-logged areas, especially through limited seedbed preparation and mechanical disturbance.

There is increasing recognition of the importance of ecologically sustainable forest management, including forest biodiversity conservation. Knowledge of the effects of forest practices on flora values can be gained by comparing the floristics of natural and harvested forest stands at the same stage of development. This paper presents the results from a comparative study of natural and managed forest regeneration in Eucalyptus regnans F.Muell dominated forests in the Victorian Central Highlands. The vascular floristics about a decade after clear-fell harvesting operations differed significantly from the floristics of similarly aged forest regenerating after wildfire. In clear-felled areas, weed and sedge species occurred more frequently than on wildfire sites and Acacia dealbata Link was much more abundant, whereas resprouting shrubs, tree ferns and most ground-fern species were more abundant in wildfire regeneration. The low survival rate of resprouting species reported in an increasing number of studies suggests that soil disturbance is likely to be a major contributor to differences. The floristics of sites burned by intense wildfire differed significantly from those subjected to less intense wildfire, indicating that considerable variation in floristics can occur under a natural disturbance regime. The failure of the clear-fell regeneration to fit within this broad natural variability suggests that clear-fell harvesting alters the natural regeneration processes. As species composition in these forests is largely determined by the initial floristic composition after disturbance, this paper provides evidence that some clear-felled regrowth forests may remain different in structure and composition to forests regenerating after natural disturbances.

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1. The secondary salinisation of wetlands is a global problem that poses a great threat to most freshwater biodiversity, including amphibians. We examined tadpole diversity in relation to wetland conductivity (our proxy for salinity) in wetlands in south-eastern Australia to better understand (i) how salinity and amphibian diversity interact and (ii) the threat posed by secondary salinisation. 2. Six tadpole species were trapped in 56 wetlands that reflected a typical salinity gradient for the study region. We developed Bayesian models to examine the relationships between conductivity and both the probability of species occupancy and expected number of species with the imperfect detection probability of species accounted for in the models. 3. The probability of occupancy for all species and expected species number was negatively associated with wetland conductivity. Our results predict that conductivity should not limit tadpole presence below about 3000 lS cm )1 at 25°C (approximately 6% seawater) in the region, but will largely exclude amphibian larvae beyond about 6000 lS cm )1 at 25°C (approximately 12% seawater). 4. We also detected subtle among-species differences in salinity tolerance. The results reported here show that tadpoles in the study region are likely to be negatively affected by projected future increases in salinisation.

Radiocarbon ages were derived from 12 individuals representing four species of woody understorey plants growing in the Eucalyptus regnans dominated Wet Forests of Victoria's Central Highlands. Cyathea australis, Dicksonia antarctica and Olearia argophylla are common and often dominate the understorey. The fourth species, Persoonia arborea, is a small understorey tree endemic to this region. Field observations and radiocarbon ages for these four species (up to 370 ± 70 years BP) indicate they are capable of surviving fire and are long-lived in this environment.