Regeneration of Wet Forest flora a decade after clear-felling or wildfire - is there a difference?

Abstract

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.