https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Large-scale eDNA metabarcoding survey reveals marine biogeographic break and transitions over tropical north-western Australia https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44366 Wed 12 Oct 2022 10:03:24 AEDT ]]> Modelling the spatial extent of post-fire sedimentation threat to estimate the impacts of fire on waterways and aquatic species https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:53278 10 million ha of temperate and subtropical forests. Methods: We integrated an existing soil erosion model with fire severity mapping and rainfall data to estimate the spatial extent of post-fire sedimentation threat in waterways and in basins and the potential exposure of aquatic species to this threat. We validated the model against field observations of sedimentation events after the 2019–20 fires. Results: While fires overlapped with ~27,643 km of waterways, post-fire sedimentation events potentially occurred across ~40,449 km. In total, 55% (n = 85) of 154 basins in the study region may have experienced substantial post-fire sedimentation. Ten species—including six Critically Endangered—were threatened by post-fire sedimentation events across 100% of their range. The model increased the estimates for potential impact, compared to considering fire extent alone, for >80% of aquatic species. Some species had distributions that did not overlap with the fire extent, but that were entirely exposed to post-fire sedimentation threat. Conclusions: Compared with estimating the overlap of fire extent with species' ranges, our model improves estimates of fire-related threats to aquatic fauna by capturing the complexities of fire impacts on hydrological systems. The model provides a method for quickly estimating post-fire sedimentation threat after future fires in any fire-prone region, thus potentially improving conservation assessments and informing emergency management interventions.]]> Mon 20 Nov 2023 13:02:59 AEDT ]]> Severe wildfires promoted by climate change negatively impact forest amphibian metacommunities https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54954 Fri 22 Mar 2024 15:30:41 AEDT ]]> Phenological shuffling of major marine phytoplankton groups over the last six decades https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40442 n = 10 taxa) tended to show a large seasonal advancement, the timing of peak abundance for dinoflagellates as group advancing 39 days over these six decades. By contrast diatoms (n = 35) did not show any change as a group in their timing of peak abundance over the time series. Granger causality testing suggested a major driver of these phenological changes has been ocean warming in general but more specifically the rate of spring temperature rise as the most important factor. We also found differences in the timing of peak abundance of harmful algal bloom taxa, with some showing peak abundance earlier while others have moved later. Main conclusions: There has been a fundamental transformation of the classic seasonal progression from blooms of diatoms to dinoflagellates, which lies at the heart of temperate marine food chains, as the classic bimodal diatom and dinoflagellate seasonal peaks are eroded to a more continuous, single, longer-lasting phytoplankton peak. This phenological shuffling within and between major taxonomic groups is likely to have profound implications for the transfer of energy to higher trophic levels.]]> Fri 22 Jul 2022 14:37:23 AEST ]]>