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Fire is a major ecological driver in many Australian ecosystems, and large-scale wildfires can impact on faunal assemblages at a landscape scale. Monitoring the response of the avian community and individual bird species following...
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Fire is a major ecological driver in many Australian ecosystems, and large-scale wildfires can impact on faunal assemblages at a landscape scale. Monitoring the response of the avian community and individual bird species following a 92 039 ha wildfire in the Pilliga Forest, in temperate inland south-eastern Australia, showed an initial decline in species richness and changes in community composition, followed by gradual recovery. Recovery was not complete by the end of the seven-year study. Eighteen species (including Speckled Warbler Chthonicola sagittata and Eastern Yellow Robin Eopsaltria australis) were identified as likely to be fire sensitive and nine species (including Australian Magpie Cracticus tibicen and Red-capped Robin Petroica goodenovii) as likely to respond positively to fire at the time scale of this study. Another 11 species (including Dusky Woodswallow Artamus cyanopterus and Jacky Winter Microeca fascinans) appeared to favour burnt areas close to the fire edge. Guild-level patterns included an overall negative response to fire by insectivores, granivores/frugivores and declining woodland birds and a positive response by predators. The avian community recovered more quickly at burnt sites close to (within 2 km of) the fire edge compared to more remote sites more than 4 km from unburnt habitat, suggesting that proximity to unburnt areas (and therefore fire extent) is likely to be a key consideration in understanding the post-fire recovery of birds.
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Context Ensembles of artificial neural network models can be trained to predict the continuous characteristics of vegetation such as the foliage cover and species richness of different plant functional groups. Objectives Our first...
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Context Ensembles of artificial neural network models can be trained to predict the continuous characteristics of vegetation such as the foliage cover and species richness of different plant functional groups. Objectives Our first objective was to synthesise existing site-based observations of native plant species to quantify summed percentage foliage cover and species richness within four functional groups and in totality. Secondly, we generated spatially-explicit, continuous, landscape-scale models of these functional groups, accompanied by maps of the model residuals to show uncertainty. Methods Using a case study from New South Wales, Australia, we aggregated floristic observations from 6806 sites into four common plant growth forms (trees, shrubs, grasses and forbs) representing four different functional groups. We coupled these response data with spatially-complete surfaces describing environmental predictors and predictors that reflect landscape-scale disturbance. We predicted the distribution of foliage cover and species richness of these four plant functional groups over 1.5 million hectares. Importantly, we display spatially explicit model residuals so that end-users have a tangible and transparent means of assessing model uncertainty. Results Models of richness generally performed well (R-2 0.43-0.63), whereas models of cover were more variable (R-2 0.12-0.69). RMSD ranged from 1.42 (tree richness) to 29.86 (total native cover). MAE ranged from 1.0 (tree richness) to 20.73 (total native foliage cover). Conclusions Continuous maps of vegetation attributes can add considerable value to existing maps and models of discrete vegetation classes and provide ecologically informative data to support better decisions across multiple spatial scales.
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The aerosol monitoring provides air quality information to the community. Policy and community groups often want to know more than the level of mass concentration, that is, a description of what type of aerosols are being reported...
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The aerosol monitoring provides air quality information to the community. Policy and community groups often want to know more than the level of mass concentration, that is, a description of what type of aerosols are being reported. There is a need to more objectively and efficiently, that is, in near real time, classify aerosols. Different instruments are used in different networks, raising the issue of comparability. In New South Wales, Australia, the Air Quality monitoring network uses Tapered Element Oscillating Microbalances (TEOM). The Community DustWatch network uses DustTrak (R) and subjectively classifies its data into dust, smoke and fog.
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Drivers of soil organic carbon (SOC) storage are likely to vary in importance in different regions and at different depths due to local factors influencing SOC dynamics. This paper explores the factors influencing SOC to a depth o...
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Drivers of soil organic carbon (SOC) storage are likely to vary in importance in different regions and at different depths due to local factors influencing SOC dynamics. This paper explores the factors influencing SOC to a depth of 30 cm in eastern Australia.
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Restoration goals often involve the addition of new species to resident, degraded communities but in box gum woodlands such restoration is often constrained by competition from persistent exotic annuals that control critical ecolo...
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Restoration goals often involve the addition of new species to resident, degraded communities but in box gum woodlands such restoration is often constrained by competition from persistent exotic annuals that control critical ecological processes. Nutrient reduction (via carbon addition) and seed bank depletion are two approaches to reduce competition from exotic annuals but to be effective these treatments must allow establishment of species such as native grasses. This experiment was conducted in two degraded Austrostipa understoreys in the box gum woodlands of south-east Australia. It compares the effects of carbon addition (sugar), seed depletion (spring burning or spring grazing) and combinations of carbon addition and seed depletion treatments on the establishment of C3 and C4 native grasses, and measured the effects of their establishment on soil nitrate concentration and exotic annuals. Treatments that reduced exotic annual abundance did not increase initial germination of the C4 native grasses, Bothriochloa or Themeda. However, sugar increased seedling survival of Themeda and Bothriochloa and grazing increased seedling survival of Bothriochloa, presumably by reducing effects of exotic annuals. Poa and Rytidosperma (C3 native grasses) failed to establish. Although we were unable to detect any reduction in soil nitrate concentration, swards with successful recruitment of C4 grasses suppressed exotic annuals more than the Austrostipa-only swards at one site (the other was affected by wildfire). Further, Austrostipa-Themeda swards were more effective than Austrostipa-Bothriochloa for suppressing exotics, pointing to a role for both functional and species identity in the degree of resistance conferred.
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Since European settlement, woodlands have undergone significant structural and compositional changes in semiarid SE Australia. With logging, introduced grazing and declines in fire frequency, fire-sensitive Callitris glaucophylla ...
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Since European settlement, woodlands have undergone significant structural and compositional changes in semiarid SE Australia. With logging, introduced grazing and declines in fire frequency, fire-sensitive Callitris glaucophylla has regenerated densely in woodlands dominated by C. glaucophylla and fire-tolerant Eucalyptus species. Since little is known about long-term competitive interactions between sapling regeneration and canopy trees, we examined: (1) how established Eucalyptus and Callitris canopy trees influence survival, growth and reproduction of Callitris saplings; (2) whether dense Callitris regeneration affects canopy tree health during drought; and (3) whether these patterns differ along a rainfall gradient (363621mmyear-1). Callitris saplings beneath tree canopies were less dense, smaller, and less likely to fruit than isolated saplings in gaps along the rainfall gradient. Callitris trees surrounded by Callitris regeneration had greater mortality than those without surrounding regeneration; Eucalyptus trees were more likely to be drought stressed at the lower end of the rainfall gradient, where canopy trees were at higher densities. The results suggest that canopy trees reduce the density rather than exclude Callitris regeneration, and that the regeneration contributes to mortality of Callitris canopy trees during drought. The trend towards increasing Callitris dominance is expected to continue over time, owing to the paucity of Eucalyptus recruitment.
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