21 resultados para Southern armyworm

em Deakin Research Online - Australia


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A small fauna of 11 species belonging to 10 genera of Permian Brachiopoda from the lower part of the Qubuerga Formation outcropping near Shengmi village in the Qomolangma region of southern Xizang (Tibet) is figured and new taxa are described. New taxa are Quinquenella semiglobosa and Costatumulus shengmiensis. The fauna is most likely of Wuchiapingian (Djhulfian) age as indicated by the majority of the brachiopod species.

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A localised aggregation of blue whales. which may be pygmy blue whales (B. m. brevicauda), occurs in southern Australian coastal waters (between I39°45'E-143°E) during summer and autumn (December-May), where they feed on coastal krill (Nyctiphanes australis). a species which often forms surface swarms. While the abundance of blue whales using this area is unknown, up to 32 blue whales have been sighted in individual aerial  surveys. Krill appear to aggregate in response to enhanced productivity  resulting from the summer-autumn wind-forced Bonney Coast upwelling along the continental shelf. During the upwelling's quiescent (winter-spring) period. blue whales appear to be absent from the region. Krill surface  swarms have been associated with 48% of 261 blue whale sightings since 1998, with direct evidence of feeding observed in 36% of all sightings. Mean blue whale group size was 1.55 (SD =0.839), with all size classes represented including calves. This seasonally predictable upwelling system is evidently a regular feeding ground for blue whales, and careful  management of human activities is required there.

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A brachiopod fauna of 16 species belonging to 11 genera and three genera and species indeterminate from the middle and upper parts of the Juripu Formation in the Yarlung-Zangbo (Indus-Tsangbo) Suture zone (=Yarlung-Zangbo River zone), southern Tibet, is described and figured for the first time. A new species, Taeniothaerus zhongbaensis, is described. The fauna is comparable with that in the Kalabagh Member of the Wargal Formation of the Salt Range, Pakistan, and is considered to be most likely Capitanian (late Guadalupian/Middle Permian) to Wuchiapingian (early Lopingian/early Late Permian) in age, as indicated by the majority of the brachiopod species and by being constrained by an underlying fusulinacean fauna (Parafusulina Zone) and an overlying ammonite fauna (Cyclolobus fauna).

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Morphology has often been used as an indicator of variability within species. The present study investigated morphological and physiological characteristics of isolates of Phytophthora cinnamomi collected from diseased vegetation communities at Anglesea, Victoria, and isolates collected from other regions in the State. Characteristics studied included growth rate on potato-dextrose agar (PDA), corn-meal agar and V8-juice agar at 24°C, growth rate on V8 agar at 15°C, colony morphology on PDA, sporangial and gametangial morphology, sporangial production and mating type. Phenotypic variation was demonstrated in radial growth rate, colony morphology and sporangial dimensions. Sporangial and oogonial dimensions and sporangial production were not significantly different between isolates from different geographical regions. All isolates were found to be of the A2 mating type suggesting variation was derived asexually. Paragynal associations, in an organism characteristically defined as amphigynal, were observed following crossing with A1 isolates. This is the first such study undertaken in southern Victoria. The findings highlight the importance of appropriate management of an area of such high conservation value as the Anglesea Heath to contain the current infection and to prevent introduction of new isolates into the area.

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Caging and a mark–recapture design were used to estimate the growth rate of the brittle, infaunal bivalve Soletellina alba in the Hopkins River estuary. The growth of both caged and uncaged individuals was monitored at three sites near the mouth of the estuary over 180 days. Growth rates did not differ for caged and uncaged bivalves, or for bivalves subject to different amounts of handling, or between sites. Growth did differ between consecutive time intervals, which was attributable to negligible growth occurring during the colder months of autumn/winter. Comparisons of the condition (as indicated by total mass for length3) of S. alba were inconsistent between sites for caged and uncaged bivalves and for those subject to different amounts of handling. Soletellina alba is a rapidly growing bivalve with mean growth rates for the three time intervals being 0.04±0.002 mm day−1 in summer, 0.02±0.001 mm day−1 in autumn and 0.03±0.001 mm day−1 from summer to winter. Using existing literature, it was shown that a significant relationship exists between maximum shell length and onset of sexual maturity in bivalve molluscs. This relationship predicts that S. alba should reach the onset of sexual maturity at 15.8 mm length. Therefore, it appears that it may be possible for juvenile S. alba (<1 mm) to grow, reach sexual maturity and reproduce in between annual mass-mortality events caused by winter flooding.

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Sphacelaria biradiata Askenasy is a little known but common brown alga of southern Australian coasts. This paper describes its reproduction. Populations of S. biradiata reproduced asexually by vegetative propagules in all localities examined. The propagules were produced throughout the year and did not appear to be affected by season, although, if sexual structures occurred, propagule numbers declined. Sexual reproduction can occur and involves an alternation of generations, but it is a rare event. Gametophytes may produce male gametangia, female gametangia or both. Male gametangia, however, are extremely rare and are described for the first time. Production of female gametangia was influenced by season and occurred at all areas studied. The sexual behaviour of the male and female gametes is described.

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The southern bent-wing bat (Miniopterus schreibersii bassanii) is an insectivorous, obligate cave dwelling species found in south-eastern South Australia and western Victoria, Australia. In recent times, the finger of blame for an apparent population decline at Bat Cave, Naracoorte (one of only two known maternity roosts for this species, the other being Starlight Cave, Warrnambool) has been pointed at pesticide use in the region, following the finding of organochlorine and organophosphate insecticide residues in bat guano. This study sampled juvenile southern bent-wing bats from Bat Cave and Starlight Cave, and determined DDT, DDD and DDE concentrations in liver, pectoral muscle, brain and back-depot fat tissues.

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In recent years, predictive habitat distribution models, derived by combining multivariate statistical analyses with Geographic Information System (GIS) technology, have been recognised for their utility in conservation planning. The size and spatial arrangement of suitable habitat can influence the long-term persistence of some faunal species. In southwestern Victoria, Australia, populations of the rare swamp antechinus (Antechinus minimus maritimus) are threatened by further fragmentation of suitable habitat. In the current study, a spatially explicit habitat suitability model was developed for A. minimus that incorporated a measure of vegetation structure. Models were generated using logistic regression with species presence or absence as the dependent variable and landscape variables, extracted from both GIS data layers and multi-spectral digital imagery, as the predictors. The most parsimonious model, based on the Akaike Information Criterion, was spatially extrapolated in the GIS. Probability of species presence was used as an index of habitat suitability. A negative association between A. minimus presence and both elevation and habitat complexity was evidenced, suggesting a preference for relatively low altitudes and a vegetation structure of low vertical complexity. The predictive performance of the selected model was shown to be high (91%), indicating a good fit of the model to the data. The proportion of the study area predicted as suitable habitat for A. minimus (Probability of occurrence greater-or-equal, slanted0.5) was 11.7%. Habitat suitability maps not only provide baseline information about the spatial arrangement of potentially suitable habitat for a species, but they also help to refine the search for other populations, making them an important conservation tool.

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The concentrations of 12 trace metals were assessed in wild and cultured specimens of blacklip abalone, Haliotis rubra, from each of two sites, Geelong and Port Fairy, in Victoria, Australia. Cadmium, copper, iron and zinc were quantified in the foot muscle of specimens from all four populations but the concentrations of aluminium, arsenic, beryllium, chromium, lead, manganese, nickel and vanadium were below the detection limits of the instrumental techniques employed. When similar sized specimens from each population were compared, the concentrations of each of the quantifiable metals varied according to location. The Geelong wild population had the highest or equal highest concentrations of each metal. Metal concentrations in the wild populations were usually greater than or equal to the concentrations in the corresponding cultured population. The concentrations of the regulated essential elements, copper and zinc, decreased with an increase in abalone length whereas the concentrations of iron, manganese and cadmium were independent of length. Metal concentrations in H. rubra from all sites complied with the Australian Food Code and other standards of food safety.


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These multiple framings of our reflections on environmental education research in southern Africa are written as dilemmas of interpretation that aim to disrupt any temptation to generalise or essentialise its qualities and characteristics. Recognising that research is a textual practice, we use J. M. Coetzee's portrayal of the dilemmas faced by African novelists as a point of departure in reflecting on the changing landscape of environmental education research in southern Africa as we have experienced it over six years. We provide readings framed by reference to post-colonialism, changing epistemologies and methodologies, contexts of transformation and tension, the influence of international organisations such as the United Nations and its instrumentalities, and concerns about human rights and accountability. We conclude by affirming the post-colonialist trajectories of environmental education research in southern Africa and speculating on the distinctive possibilities that recovering ubuntu (an ethic of sharing and hospitality) might offer to researchers in this region.

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Territory cults in southern Lao PDR exemplify the importance of ritual for the production of locality in an era of mobility. Here, the idea of village expressed in ritual incorporates scattered members who have ties of history and affection to village households—a view of residency that is extra-verted, inclusive and traverses space.

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Ground-foraging birds of temperate woodlands of southern Australia are prominent among bird species considered to be susceptible to population decline. We examined the foraging ecology, including foraging substrates, actions and heights, of 13 ground-foraging species at four woodland sites in northern Victoria. Nine species are regarded as declining in southern Australia and four are considered common. Ten foraging substrates were identified, of which leaf-litter (54% of observations) and bare ground (17%) were most frequently used. In all woodland sites, litter was used more frequently than expected from its proportional cover. Bare ground was frequently used as a substrate by individual species, and fallen timber and grass were important for some species. Most species were generalists in their use of substrates. Six foraging actions were observed, of which gleaning and pouncing were most frequently recorded. All species foraged close to the ground and four foraged almost entirely at ground level. For pouncing birds, dead branches and fallen timber were the most important launch substrates from which pouncing actions were initiated. Eight of the 13 species differed in some aspect of their foraging ecology between woodland sites, especially in relation to the use of substrates (seven species). Fewer species (four) displayed differences in foraging ecology between seasons, with the greatest seasonal variation being in use of foraging substrates (three species). Overall, no significant differences were evident in the foraging ecologies of common and declining species. Species in both groups encompassed a wide range of foraging behaviours. Owing to this range in foraging ecology, the conservation of diverse assemblages of ground-foraging birds requires the maintenance of heterogeneous ground layers and careful management of disturbance processes.

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In recent times, the apparent population decline of the southern bent-wing bat (Miniopterus schreibersii bassanii) at Bat Cave, Naracoorte has been ascribed to pesticide use in the region, following the finding of organochlorine and orgaonophosphate insecticide residues in bat guano. Adult southern bent-wing bats were collected from Bat Cave and Starlight Cave in 2003. Organochlorine contaminants were detected in all carcass samples: p,p′-DDE was by far the most dominant contaminant with concentrations ranging from 11 000 to 59 000 ng g−1, followed by p,p′-DDT (110–1600 ng g−1), p,p′-DDD (35–620 ng g−1), ∑PCBs (33–490 ng g−1), ∑chlordane and related compounds (7.9–270 ng g−1), HCB (1.6–120 ng g−1), HP epox. (3.1–230 ng g−1), TCPMOH (3.8–38 ng g−1), ∑HCHs (1.4–9.6 ng g−1), and TCPMe (0.1–4.2 ng g−1) (all values on lipid-weight basis). No significant difference in DDE, DDD, DDT, ∑DDT, ∑PCB, trans-chlordane, heptachlor epoxide, trans-nonachlor, α-HCH, β-HCH, γ-HCH, TCPMOH or TCPMe concentrations were observed either between sexes within sites, or between sites (p > 0.05). However, there were significant differences in HCB and oxychlordane concentrations between sexes and between sites (p < 0.05), between site differences in cis-nonachlor concentrations in male bats (p < 0.05), and cis-chlordane concentrations between sexes at Starlight Cave, and between males of each site (p < 0.05). There were also significant differences in the liver concentrations of some metals between sexes within sites (Ag, Cd, Co, Cu, Pb, Se, Zn), and between sites (Ag, Cd, Co, Cu, Hg, Pb, Se, V, Zn). Clustering or grouping of sites was observed when the OC data was expressed on a lipid-weight basis. These inter-site differences in OC concentrations reflect local exposure over a period of time, and do not unambiguously support any suggestion that we are witnessing incipient speciation. However, for conservation purposes, it may be prudent to assume that there are two sub-populations of M. s. bassani feeding in different locations in this region of southern Australia, rather than the single homogeneous population suggested by genetic studies.

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The Middle Permian Wandrawandian Siltstone at Warden Head near Ulladulla in the southern Sydney Basin is dominated by fossiliferous siltstone and mudstone, with a large amount of dropstones (lonestones) and some pebbly sandstone beds. Two general types of deposits are recognised from the cliff succession in view of the timing and mechanism of their formation. One is represented by the background (or primary) deposits of offshore to slope environments with abundant dropstones of glacial marine origin. This facies occurs throughout the cliff sections at Warden Head. The second type is distinguished by secondary, soft-sediment deformational deposits and structures of the primary (background) deposits, and comprises three successive layers of sandy mudstone dikes. In the second type of deposit, metre scale, laterally extensive syn-depositional slump deformation structures occur extensively in the middle part of the Wandrawandian Siltstone. The deformation structures vary in morphology and pattern, including large-scale complex-type folds, flexural stratification, concave-up structures, small-magnitude -faults accompanied by folding and brecciation. The slumps and associated syn-depositional structures are herein attributed to penecontemporaneous deformations of soft sediments (mostly mud and silty mud), formed as a result of mass movement of unconsolidated and/or semi-consolidated substrate following earthquake events. The occurrence of the earthquake event deposits (or seismites) at Warden Head supports the current view that the Sydney Basin was located in a back-arc setting near the New England magmatic arc on an active continental margin during the Middle Permian, and the timing of the earthquake events is here interpreted to indicate the onset of the Hunter Bowen Orogeny in the southern Sydney Basin.

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This paper focuses on learning processes across the design curriculum of Deakin University School of Architecture and Building (Australia) through the recognition of the four learning styles - 'accommodating', 'diverging', 'assimilating' and 'converging' - that are defined in the Experiential Learning theory of Kolb. The research has been conducted to evaluate the effects of
learning style preferences on the performance of built environment students from diverse backgrounds and cultures in projects across a range of learning situations. The results of the research are being used to inform andragogical refinements that will be tested in design studio and technology lecture units studied by students of Architecture and Construction Management. The paper will focus on the results of a cross-curriculum learning style survey. The sUivey was conducted as part of a Strategic
Teaching and Learning Grant funded project currently running at Deakin as a reflexive research program aimed at resolving the learning difficulties of students collaborating in multi~disciplinary and multi~cultural team assignments. By addressing the issues of multidisciplinarity, cultural inclusiveness and the internationalisation of higher education, the research program aims ultimately at the education of graduates who are able to bring leadership to multidisciplinary design collaborations co-operating across international boundaries towards a global sustainable future.