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Wildfire severity is assumed to be an important driver of habitat availability and species' distributions in forest ecosystems. Many studies have focused on the immediate or short‐term effects of fire severity in fire‐prone ecosystems, with much less focus on how long the effect of fire severity may persist. We examined the effect of fire severity on the distribution of arboreal mammals at 3 and 10 years post‐fire, in a temperate forest ecosystem dominated by eucalypts that have strong resistance and resilience to low and high severity fire, respectively. The study took place within areas affected by the 2009 Kilmore East‐Murrindindi wildfires in south‐eastern Australia. Sites were established across a gradient of fire severity (unburnt through to canopy consumption) and surveyed at 3 and 10 years following fire. Owing to low detection rates for many species, analyses were limited to greater glider (Petauroides volans) occurrence and arboreal species richness. At both 3 and 10 years post‐fire, the greater glider was restricted to unburnt forest or sites affected only by understorey fire, which acted as fire refugia. Greater gliders were absent from sites affected by high severity, canopy‐consuming fires at both points in time. Greater glider occurrence was associated with high levels of canopy cover (>50%), which were typically those areas that were unburnt or burnt at low severity. The richness of arboreal mammals increased over time and was greater in unburnt or minimally affected forest. Our findings emphasize: (i) that fire severity is an important driver of the distribution of arboreal mammals; and (ii) the importance of recognizing longer‐term effects of fire severity in assessing species distributions, even in highly resilient forest communities. Recent advances in mapping fire severity provide new opportunities to assess the effects of fire severity on the distributional patterns of fauna in eucalypt forests. [ABSTRACT FROM AUTHOR]

Flow regulation impacts on riparian vegetation composition, often increasing the prevalence of exotic and terrestrial plant species. Environmental flows may benefit native riparian vegetation via the promotion of plant recruitment from riparian soil seedbanks, but this is dependent on an intact native seedbank. Thus, we assessed the composition of the soil seedbank of different riverine geomorphic features to determine its potential response to environmental flows. Soil seedbank samples were taken from channel bars, benches and floodplains at six sites along the Campaspe River, Australia, a heavily regulated river that receives environmental flows. These geomorphic features represent a gradient in elevation and thus flooding frequency from frequently flooded (bars) to infrequently flooded (floodplain). Seedbank samples were 'grown out' in a glasshouse, and seedlings identified and classified according to taxa, flood tolerance and origin (native or exotic). We identified 6515 seedlings across all geomorphic features and sites, with monocots most abundant. Soil seedbank composition varied between geomorphic features. Overall, seedling abundances were greater for in-channel features (bars and benches) than floodplains, but taxa richness did not vary likewise. Soil seedbanks of in-channel features were dominated by flood tolerant and native taxa, while flood intolerant and exotic taxa were generally associated with floodplains. The dominance of native flood tolerant taxa in the soil seedbanks of in-channel geomorphic features suggest these seedbanks can play an important role in the resilience of native riparian plant communities. Moreover, environmental flows are likely to play a positive role in maintaining native riparian plant communities given such conditions.

Focuses on the threats to ecosystems and biodiversity in the wet tropics bioregion of Australia. Impact of climate change on biodiversity conservation in the region; Discussion on global warming; Information on the reduction in the magnitude of climate change through mitigation.