South-western Australia Research Articles

Population structure and microhabitat preference of a threatened freshwater mussel, Westralunio carteri, in south-western Australia

Freshwater mussels are important functional components of aquatic ecosystems. Westralunio carteri is a threatened freshwater mussel species, endemic to south-western Australia, which has suffered a recent, dramatic decline in range. The density, size structure and distribution of adult mussels of this species within river reaches were investigated using quadrat searches and modelled against a range of microhabitat factors. Mussels were found from 26 sites in 14 different rivers at a mean density of 28.4 ± 2.3 individuals m−2. The distribution of W. carteri was highly aggregated within river reaches. The most important factors explaining mussel distribution were substrate grain size, substrate debris and distance from the riverbank, with finer substrate, the presence of woody debris and proximity to the riverbank associated with greater abundance of mussels. In all rivers where mussels were found, most populations appeared to be actively recruiting. However, no mussels were found in six sites, despite them having been recorded as present within the last 20 years, which suggests that the range of the species is still in decline. The identification of microhabitat requirements for W. carteri will assist in identifying suitable release sites for translocation and/or captive propagation, which may be required to prevent extinction of the species.

Study of in Vitro Antimicrobial Activity and in Vivo Wound Healing Potentiality of Leaves of Callistemon Viminalis

Callistemon viminalis, often known as the stream bottlebrush, is a tropical plant in the Myrtaceae familyand is renowned for its ability to grow rapidly in riparian zones. It is exclusively found in New South Wales,Queensland, and Western Australia. The roots of this species are entangled, which helps stabilize the soil, whichreduces the danger of erosion. This plant has antibacterial, antifungal, antioxidant, and other pharmacologicaland insecticidal abilities that are also related to other medicinal properties. This research investigates the benefits,applications, and features of several extracts obtained from components of C. viminalis (branches, flowers, fruits,bark, and leaves). Bioactive compounds were characterized in detail by noting their chemical structures. The useof C. viminalis in folk medicine was fully supported by the results. Collecting and compounding plant materials,including processing, drying, and grinding, and then doing research to screen pharmaceutical effects, are all partof making the cure. Rats had their wound healing ability tested using a method known as in vitro experimentation.This method relies on excision wounds. The capacity of the extracted substance to close wounds when appliedas an ointment was shown to be greater than in the control. The epithelization time in the standard and treatedgroups was significantly shorter than in the basic ointment base treatment group. The group treated with 5% w/wextract ointment had greater traction intensity than the control group (1.96 gm/mm2), with a significant differenceof (1.12) gm/mm2. The tensile strength of the (3.86) gm/mm2 of the 5% w/w treated group. A substantial increasein tensile strength was seen on the tenth day for both the extract level and the normal medicine.

Decadal abundance patterns in an isolated urban reptile assemblage: Monitoring under a changing climate.

Determine seasonal, annual, and decadal patterns of abundance in reptile species and assemblages occupying central Bold Park (~338 ha), an isolated urban bushland remnant in Perth, Southwestern Australia. Fenced pitfall trapping in four sampling sites, representing different habitats and fire history, over the primary reptile activity period for 35 consecutive years with over 17,000 individuals captured during 3300 days of sampling; the trapping regime was modified for the last 28 years. Sampling occurred in one of 35 global biodiversity hotspots that has a Mediterranean climate experiencing a 15% decline from the century average rainfall over the last 50 years. Twenty‐nine species were recorded, with 16 captured in 32 or more years and accounting for nearly 97% of all captures; the six most common for 81%. Three taxa became locally extinct. Activity predominates in warmer and dryer months (October to April), peaking in November–December. Species richness remained relatively constant between years with around 73% of known taxa captured annually. Assemblages did not change when analyzing the presence/absence data but moved through five statistically significant assemblages analyzing relative abundance data. Over the last 28 years, relative abundance was significantly and positively correlated with annual rainfall residuals, uniquely for the 4 years preceding annual sampling, resulting in significant changes in total assemblages and significantly similar patterns in four sample sites; the presence/absence data indicated only minor assemblage changes across sites. The number of species recorded annually remained relatively constant, but relative abundance illustrated significant temporal changes in assemblages over decades. The modeled relationship between relative abundance and annual rainfall residuals for 4 years preceding annual sampling is supported by known ecological responses and reptile demographics within this Mediterranean climate. Maintenance of urban biodiversity should consider impacts of a significantly drying climate exacerbating the extinction debt already inherent in isolated bushland populations experiencing limited immigration.

A cool spot in a biodiversity hotspot: why do tall Eucalyptus forests in Southwest Australia exhibit low diversity?

Background and aimsSouthwest Australia is a biodiversity hotspot, with greatest plant species diversity on the most severely phosphorus (P)-impoverished soils. Here, non-mycorrhizal species with highly-effective carboxylate-releasing P-acquisition strategies coexist with mycorrhizal species that are less effective at accessing P on these soils. Non-mycorrhizal carboxylate-releasing species facilitate P acquisition of mycorrhizal neighbours that are better defended against pathogens. In the Southwest Australian Biodiversity Hotspot, there are also ‘cool spots’ of low-diversity tall mycorrhizal Eucalyptus communities on P-impoverished soils. These Eucalyptus trees obviously do not require facilitation of their P acquisition by carboxylate-releasing neighbours, because these are only a minor component of the low-diversity communities. We hypothesised that in low-diversity tall Eucalyptus forests, mycorrhizal species release carboxylates to acquire P. Thus, they would not depend on facilitation, and must be strong competitors. However, because they would not depend on external mycorrhizal hyphae to acquire P, they would also not be able to access soil organic nitrogen (N), for which they would need external hyphae.MethodsSince carboxylates not only mobilise P, but also manganese (Mn), we used leaf Mn concentrations ([Mn]) in the natural habitat to proxy rhizosphere carboxylates. To verify this proxy, we also measured carboxylate exudation of targeted species with high leaf [Mn] using seedlings grown in low-P nutrient solutions.ResultsUsing these complementary approaches, we confirmed our hypothesis that dominant Eucalyptus species in ‘cool spots’ release carboxylates. Since mineralisation of organic N is associated with fractionation of N, enriching organic N with 15N while nitrate is depleted in 15N, we measured the stable N isotope composition of leaf material. The results show that dominant Eucalyptus species did not access organic N, despite being ectomycorrhizal.ConclusionsThe low diversity of tall Eucalyptus forests in southwest Australia can be explained by dominant mycorrhizal species exhibiting a carboxylate-releasing strategy. The tall eucalypts are therefore strong competitors that do not require facilitation, but also do not access organic N.

A balancing act: Biodiversity and human wellbeing considerations in the management of urban forest in a global biodiversity hotspot

Environmental and urban forest managers in cities located in highly biodiverse regions may need to balance biodiversity conservation with the provision of ecosystem services to people. However, striking this balance is not easy and many competing factors influence the decision-making process. Set in the Perth Metropolitan Area, located in the global biodiversity hotspot of the Southwestern Australia Floristic Province, this study aimed to understand: (i) the extent to which a benefits-oriented approach is used by local governments to optimise biodiversity and human wellbeing urban forest outcomes, and (ii) what other factors influence the decision-making process shaping urban forest composition. Using a social-ecological framework, we conducted semi-structured interviews with 29 local government practitioners. We found that biodiversity conservation is actively considered in the planning and management of urban forest in natural areas and parks, but rarely in streetscapes. Maximising shade and cooling, and to a lesser extent enhancing sense of place, were the key benefits actively sought in streetscapes. Parks appeared to straddle the middle ground as areas with most flexibility to accommodate multiple biodiversity and human wellbeing benefits. Yet, benefits were only some of a multitude of social-ecological factors influencing the decision-making process shaping urban forest composition. In particular, streetscapes were affected by a large number of social and political factors (e.g., perceived risk and nuisance, ad-hoc decisions by elected members), many of them leading to suboptimal urban forest outcomes. For a benefits-oriented approach to prevail in complex and contested urban spaces it is important that the decision-making process is evidence-informed and capable of handling the challenges and conflicts that are likely to arise. Reactive decision-making results in a conservative, “safe” species palette that over time defines streetscapes by what they do not do (creating disservices) rather than what they do (delivering multiple biodiversity and wellbeing benefits), which ultimately is not a desired outcome in the context of an increasingly urbanized world.

Impact of bushfires on seabird breeding islands in southwest Australia: a case study for developing a community-based model in adaptive management

Impact of bushfires on seabird breeding islands in southwest Australia: a case study for developing a community-based model in adaptive management

Local fisher knowledge reveals changes in size of blue swimmer crabs in small-scale fisheries

Fisheries stock status is generally based on time series catch and effort data sourced from independent surveys and the fishery. These methods are often expensive and can be limited temporally and spatially. Alternative methods include the use of local fisher knowledge (LFK) to identify observed changes in catch. The blue swimmer crab (Portunus armatus) supports a small-scale commercial fishery and one of the most popular recreational fisheries in south-western Australia. Previous studies identified concerns from recreational fishers over its long-term sustainability. To understand if fishers’ perceptions of change provide useful information on actual changes in the fisheries, a triangulation approach was used to assess changes in size and abundance of crabs in two estuaries (Peel-Harvey and Swan-Canning). Three types of data were used: (i) fisher recollections from 1940s to 2010s, including face-to-face interviews and online surveys; (ii) historical records from newspaper articles from 1900 to 2000; and (iii) quantitative data on size between 2006/07 and 2018/19. Results identified: (i) crabs were smaller in the Peel-Harvey, a consistent difference identified in all data sources; (ii) crab size was perceived to have decreased in the Peel-Harvey; (iii) inter-generational differences in fishers’ perceptions regarding size changes over time; and (iv) historical evidence of persistent fishers’ concerns and perceptions of changes in the fishery and wider environment. These findings are evidence of a likely decline in the average size of crabs in south-western Australia over the last century, particularly in the Peel-Harvey, and demonstrate that LFK may be a valuable source of information particularly when other data sources are lacking.

What vaccination rate(s) minimize total societal costs after 'opening up' to COVID-19? Age-structured SIRM results for the Delta variant in Australia (New South Wales, Victoria and Western Australia).

Using three age-structured, stochastic SIRM models, calibrated to Australian data post July 2021 with community transmission of the Delta variant, we projected possible public health outcomes (daily cases, hospitalisations, ICU beds, ventilators and fatalities) and economy costs for three states: New South Wales (NSW), Victoria (VIC) and Western Australia (WA). NSW and VIC have had on-going community transmission from July 2021 and were in 'lockdown' to suppress transmission. WA did not have on-going community transmission nor was it in lockdown at the model start date (October 11th 2021) but did maintain strict state border controls. We projected the public health outcomes and the economic costs of 'opening up' (relaxation of lockdowns in NSW and VIC or fully opening the state border for WA) at alternative vaccination rates (70%, 80% and 90%), compared peak patient demand for ICU beds and ventilators to staffed state-level bed capacity, and calculated a 'preferred' vaccination rate that minimizes societal costs and that varies by state. We found that the preferred vaccination rate for all states is at least 80% and that the preferred population vaccination rate is increasing with: (1) the effectiveness (infection, hospitalization and fatality) of the vaccine; (2) the lower is the daily lockdown cost; (3) the larger are the public health costs from COVID-19; (4) the higher is the rate of community transmission before opening up; and (5) the less effective are the public health measures after opening up.

A new genus for four myobatrachid frogs from the South Western Australian Ecoregion.

The southern Australian endemic genus Geocrinia Blake 1973 (Anura: Myobatrachidae) currently contains seven species, with five restricted to Western Australia and two in the south-eastern states covering parts of New South Wales, Victoria, Tasmania and South Australia. All species have a modified life history with at least some or all of the larval stage being completed terrestrially. Four of the Western Australian species have terrestrial, non-feeding tadpoles nourished by yolk until metamorphosis. The remaining species have a biphasic development with embryos developing on land followed by an aquatic tadpole stage. The presence of species groups within the Geocrinia has been recognised since the 1970s, with all relevant subsequent studies supporting a model of two groups within the genus, recovered as reciprocally monophyletic in phylogenetic analyses. We examined character traits of the seven recognised Geocrinia species, concluding that distinction of the two monophyletic groups is supported by differences in life history strategy, larval morphology, adult morphology, call structure, breeding season and geographic distribution. The differences between the two groups correspond to phylogenetic structuring for all traits except distribution. Given reciprocal monophyly, and greater variation in traits than present within other myobatrachid genera, we conclude that the two groups should be given generic distinction. We therefore describe a new genus, Anstisia gen. nov., for four Western Australian Geocrinia species, retaining three species in Geocrinia. This increases the number of recognised myobatrachid genera to 14: five are endemic to south-western Australia.

Concentrated Solar Power (CSP) Systems to Solve the Problem of the Increasing in Electricity Demand in the Summer Season in Iraq

Concentrated solar power (CSP) is the conversion of the sun's energy into thermal energy by concentrating the solar radiation by means of mirrors or any other optical element such as lenses on a receiver containing a liquid such as water, molten salt, industrial oil or compressed gas to provide heat for heating and for industrial purposes or to generate steam that rotates a turbine to produce electricity. CSP plants may contain thermal storage units to provide electrical and thermal energy during the night or when the weather is cloudy. Concentrated thermal and electrical energy generation requires high direct solar radiation (DNI) which represents 90% of the sunlight on a sunny day and its value is neglected on a cloudy day, so (CSP) is effective in the sun belt regions, which are located at latitudes between 15 and 40 degrees north and south of the equator, these regions include: the Middle East, North Africa, South Africa, India, southwestern United States, Mexico, Chile, Peru, eastern China, Australia, southern Europe and Turkey. Also, solar radiation is high at high latitudes, as dispersion is low. The best areas to install CSP plants are the areas where direct solar radiation (DNI) is greater than (2800 kwh/m2 per year). The time taken to build CSP plants is from (1-3) years depending on the size of the plant, and its operational life is more than 30 years. The area needed by these plants is 2 hectares per megawatt. This article highlights on the systems for generating electric power from concentrated solar energy and presents the different fluids used in heat transfer, as well as the methods of thermal storage.

Evaluating data quality in the Australian and New Zealand dialysis and transplant registry using administrative hospital admission datasets and data-linkage.

Background: Clinical quality registries provide rich and useful data for clinical quality monitoring and research purposes but are susceptible to data quality issues that can impact their usage. Objective: This study assessed the concordance between comorbidities recorded in the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry and those in state-based hospital admission datasets. Method: All patients in New South Wales, South Australia, Tasmania, Victoria and Western Australia recorded in ANZDATA as requiring chronic kidney replacement therapy (KRT) between 01/07/2000 and 31/12/2015 were linked with state-based hospital admission datasets. Coronary artery disease, diabetes mellitus, cerebrovascular disease, chronic lung disease and peripheral vascular disease recorded in ANZDATA at each annual census date were compared overall, over time and between different KRT modalities to comorbidities recorded in hospital admission datasets, as defined by the International Classification of Diseases (ICD-10-AM), using both the kappa statistic and logistic regression analysis. Results: 29, 334 patients with 207,369 hospital admissions were identified. Comparison was made at census date for every patient comparison. Overall agreement was "very good" for diabetes mellitus (92%, k = 0.84) and "poor" to "fair" (21-61%, k = 0.02-0.22) for others. Diabetes mellitus recording had the highest accuracy (sensitivity 93% (±SE 0.2) and specificity 93% (±SE 0.2)), and cerebrovascular disease had the lowest (sensitivity 54% (±SE 0.2) and specificity 21% (±SE 0.3)). The false positive rates for cerebrovascular disease, peripheral vascular disease and chronic airway disease ranged between 18 and 33%. The probability of a false positive was lowest for kidney transplant patients for all comorbidities and highest for patients on haemodialysis. Conclusions and Implications: Agreement between the clinical quality registry and hospital admission datasets was variable, with the prevalence of comorbidities being higher in ANZDATA.

Geoscience Poster G6: Petrophysical characterisation of the Neoproterozoic and Cambrian successions in the Officer Basin

Poster G6 The Neoproterozoic–Paleozoic Officer Basin, located in South Australia and Western Australia, remains a frontier basin for energy exploration, with significant uncertainty due to a paucity of data. As part of Geoscience Australia’s Exploring for the Future (EFTF) program, the objective of this study is to derive the petrophysical properties and to characterise potential reservoirs in the Neoproterozoic–Cambrian sedimentary succession in the Officer Basin through laboratory testing and well log interpretation using both conventional and neural network methods. Laboratory measurements of 41 legacy core samples provide the relationships between gas permeability, Klinkenberg corrected permeability, and nano-scale permeability, as well as grain density, effective and total porosity for various rock types. Conventional log interpretation generates the volume fraction of shale, effective and total porosity from gamma ray and lithology logs. A self-organising map (SOM) was used to cluster the well log data to generate petrophysical group/class index and probability profiles for different classes. Neural network technology was employed to approximate porosity and permeability from logs, conventional interpretation results and class index from SOM modelling. The Neoproterozoic−Cambrian successions have the potential to host both conventional and tight hydrocarbon reservoirs. Neoproterozoic successions are demonstrated to host mainly tight reservoirs with the range in average porosity and geometric mean permeability of 4.77–6.39% and 0.00087–0.01307 mD, respectively, in the different sequences. The range in average porosity and geometric mean permeability of the potential Cambrian conventional reservoirs is 14.54−26.38% and 0.341−103.68 mD, respectively. The Neoproterozoic shales have favourable sealing capacities. This work updates the knowledge of rock properties to further the evaluation of the resource potential of the Officer Basin. To access the poster click the link on the right. To read the full paper click here

Geoscience Poster G8: Geomechanical rock properties of the Officer Basin

Poster G8 The Officer Basin spanning South Australia and Western Australia is the focus of a regional stratigraphic study being undertaken as part of the Exploring for the Future (EFTF) program, an Australian Government initiative dedicated to increasing investment in resource exploration in Australia. Despite numerous demonstrated oil and gas shows, the Officer Basin remains a frontier basin for energy exploration with significant uncertainties due to data availability. Under the EFTF Officer–Musgrave Project, Geoscience Australia acquired new geomechanical rock property data from forty core samples in five legacy stratigraphic and petroleum exploration wells that intersected Paleozoic and Neoproterozoic aged intervals. These samples were subjected to unconfined compressive rock strength tests, Brazilian tensile strength tests and laboratory ultrasonic measurements. Petrophysical properties were also characterised via X-ray computerised tomography scanning, grain density and porosity-permeability analysis. Accurate characterisation of static geomechanical rock properties through laboratory testing is essential. In the modern exploration environment, these datasets are a precompetitive resource that can simplify investment decisions in prospective frontier regions such as the Officer Basin. To access the poster click the link on the right. To read the full paper click here

Microbial Community Structure Is Most Strongly Associated With Geographical Distance and pH in Salt Lake Sediments.

Salt lakes are globally significant microbial habitats, hosting substantial novel microbial diversity and functional capacity. Extremes of salinity and pH both pose major challenges for survival of microbial life in terrestrial and aquatic environments, and are frequently cited as primary influences on microbial diversity across a wide variety of environments. However, few studies have attempted to identify spatial and geochemical contributions to microbial community composition, functional capacity, and environmental tolerances in salt lakes, limiting exploration of novel halophilic and halotolerant microbial species and their potential biotechnological applications. Here, we collected sediment samples from 16 salt lakes at pH values that ranged from pH 4 to 9, distributed across 48,000 km2 of the Archaean Yilgarn Craton in southwestern Australia to identify associations between environmental factors and microbial community composition, and used a high throughput culturing approach to identify the limits of salt and pH tolerance during iron and sulfur oxidation in these microbial communities. Geographical distance between lakes was the primary contributor to variation in microbial community composition, with pH identified as the most important geochemical contributor to variation in microbial community composition. Microbial community composition split into two clear groups by pH: Bacillota dominated microbial communities in acidic saline lakes, whereas Euryarchaeota dominated microbial communities in alkaline saline lakes. Iron oxidation was observed at salinities up to 160 g L–1 NaCl at pH values as low as pH 1.5, and sulfur oxidation was observed at salinities up to 160 g L–1 NaCl between pH values 2–10, more than doubling previously observed tolerances to NaCl salinity amongst cultivable iron and sulfur oxidizers at these extreme pH values. OTU level diversity in the salt lake microbial communities emerged as the major indicator of iron- and sulfur-oxidizing capacity and environmental tolerances to extremes of pH and salinity. Overall, when bioprospecting for novel microbial functional capacity and environmental tolerances, our study supports sampling from remote, previously unexplored, and maximally distant locations, and prioritizing for OTU level diversity rather than present geochemical conditions.

δ18O as a tracer of PO43− losses from agricultural landscapes

Accurately tracing the sources and fate of excess PO43− in waterways is necessary for sustainable catchment management. The natural abundance isotopic composition of O in PO43− (δ18OP) is a promising tracer of point source pollution, but its ability to track diffuse agricultural pollution is unclear. We tested the hypothesis that δ18OP could distinguish between agricultural PO43− sources by measuring the integrated δ18OP composition and P speciation of contrasting inorganic fertilisers (compound vs rock) and soil textures (sand, loam, clay) in southwestern Australia. δ18OP composition differed between the three soil textures sampled across six livestock farms: sandy soils had lower overall δ18OP values (21 ± 1‰) than the loams (23 ± 1‰), which corresponded with a smaller, but more readily leachable, PO43− pool. Fertilisers had greater δ18OP variability (∼8‰), with fluctuations due to type and manufacturing year. Consequently, catchment ‘agricultural soil leaching’ δ18OP signatures could span from 18 to 25‰ depending on both fertiliser type and timing (lag between application and leaching). These findings emphasise the potential of δ18OP to untangle soil-fertiliser P dynamics under controlled conditions, but that its use to trace catchment-scale agricultural PO43− losses is limited by uncertainties in soil biological P cycling and its associated isotopic fractionation.

Where did the Kontum Massif in central Vietnam come from?

The Kontum Massif (KTM) is the largest Precambrian basement exposure in the Indochina Block, Southeast Asia. The compositions and formation ages of the KTM basement rocks and the paleo-position of the KTM in Proterozoic supercontinents have not been well constrained. Zircon U-Pb-Hf isotopic data of sixteen samples from the KTM in this study indicate that the KTM basement consists mainly of different units of metasedimentary rocks. These sedimentary rocks were deposited in five periods, late Paleoproterozoic (G1, 1.80–1.65 Ga), late Paleoproterozoic - early Mesoproterozoic (G2, 1.74–1.45 Ga), Mesoproterozoic (G3, 1.4–1.1 Ga), late Mesoproterozoic - early Neoproterozoic (G4, 1.1–0.81 Ga), and late Neoproterozoic - early Paleozoic (G5, 0.61–0.51 Ga), and underwent three phases of metamorphism in the early Paleozoic (501–415 Ma), late Paleozoic (371–331 Ma), and Indosinian (272–235 Ma). The G1 and G2 sedimentary rocks have abundant Neoarchean (2.63–2.48 Ga) and late Paleoproterozoic (1.83–1.74 Ga) detritus, and the G3 and G4 sedimentary rocks consist mainly of late Paleoproterozoic (1.74–1.72 Ga) and middle Mesoproterozoic (1.41–1.35 Ga) clastic materials. The G5 sedimentary rocks are characterized by consecutive Mesoproterozoic detrital zircon age spectra with a wide age peak at 1.06–1.01 Ga, much different from the G1 to G4 sedimentary rocks. Most Archean detrital zircons show juvenile Hf isotopes, whereas late Paleoproterozoic, middle Mesoproterozoic, and Grenvillian zircons show large Hf-isotope variations. Most detrital zircons are exotic because coeval igneous rocks have not been identified in the KTM (or elsewhere in Indochina), except ∼1.44 Ga ones.Comprehensive comparisons of detrital zircon U-Pb, Hf isotopes and sedimentary environments of these five units of sedimentary rocks with the extensive magmatism and coeval siliciclastic rocks in different cratons and microcontinents suggest that most of the Precambrian sediments in the KTM were derived from southwestern Laurentia, and the KTM has maintained a long-time connection with southwestern Laurentia for about one billion years from the G1 to the G4. The KTM was adjacent to Hainan Island and Tasmania during the G3-G4 deposition. The U-Pb ages and Hf isotopes of detrital zircons and sedimentary environment of the G5 sedimentary rocks indicate that the KTM was located on the northern margin of East Gondwana and near South China, India and western Australia, consistent with previous configurations for the Indochina Block. Therefore, the KTM, together with South China and Hainan Island, experienced quick northward movement from southwestern Laurentia to the northern margin of East Gondwana during the G4 (ca 1.10–0.81 Ga) to the G5 (0.61–0.51 Ga), which is also supported by new paleomagnetic data.

Citizen scientists track a charismatic carnivore: Mapping the spread and impact of the South African Mantis (Miomantidae, Miomantis caffra) in Australia

The recent integration of citizen science with modern technology has greatly increased its applications and has allowed more people than ever to contribute to research across all areas of science. In particular, citizen science has been instrumental in the detection and monitoring of novel introduced species across the globe. This study provides the first records of Miomantis caffra Saussure, 1871, the South African Mantis, from the Australian mainland and uses records from four different citizen science and social media platforms in conjunction with museum records to track the spread of the species through the country. A total of 153 wild mantises and oothecae were observed across four states and territories (New South Wales, Norfolk Island, Victoria, and Western Australia) between 2009 and 2021. The large number of observations of the species in Victoria and the more recent isolated observations in other states and territories suggest that the species initially arrived in Geelong via oothecae attached to plants or equipment, likely from the invasive population in New Zealand. From there it established and spread outwards to Melbourne and eventually to other states and territories, both naturally and with the aid of human transport. We also provide a comparison of M. caffra to similar native mantises, specifically Pseudomantis albofimbriata (Stål, 1860), and comment on the potential impact and further spread of the species within Australia. Finally, we reiterate the many benefits of engaging directly with citizen scientists in biodiversity research and comment on the decision to include them in all levels of this research investigation.

Petrophysical characterisation of the Neoproterozoic and Cambrian successions in the Officer Basin

The Neoproterozoic–Paleozoic Officer Basin, located in South Australia and Western Australia, remains a frontier basin for energy exploration, with significant uncertainty due to a paucity of data. As part of Geoscience Australia’s Exploring for the Future (EFTF) program, the objective of this study is to derive the petrophysical properties and to characterise potential reservoirs in the Neoproterozoic–Cambrian sedimentary succession in the Officer Basin through laboratory testing and well log interpretation using both conventional and neural network methods. Laboratory measurements of 41 legacy core samples provide the relationships between gas permeability, Klinkenberg corrected permeability, and nano-scale permeability, as well as grain density, effective and total porosity for various rock types. Conventional log interpretation generates the volume fraction of shale, effective and total porosity from gamma ray and lithology logs. A self-organising map (SOM) was used to cluster the well log data to generate petrophysical group/class index and probability profiles for different classes. Neural network technology was employed to approximate porosity and permeability from logs, conventional interpretation results and class index from SOM modelling. The Neoproterozoic−Cambrian successions have the potential to host both conventional and tight hydrocarbon reservoirs. Neoproterozoic successions are demonstrated to host mainly tight reservoirs with the range in average porosity and geometric mean permeability of 4.77–6.39% and 0.00087–0.01307 mD, respectively, in the different sequences. The range in average porosity and geometric mean permeability of the potential Cambrian conventional reservoirs is 14.54−26.38% and 0.341−103.68 mD, respectively. The Neoproterozoic shales have favourable sealing capacities. This work updates the knowledge of rock properties to further the evaluation of the resource potential of the Officer Basin.

Geomechanical rock properties of the Officer Basin

The Officer Basin spanning South Australia and Western Australia is the focus of a regional stratigraphic study being undertaken as part of the Exploring for the Future (EFTF) program, an Australian Government initiative dedicated to increasing investment in resource exploration in Australia. Despite numerous demonstrated oil and gas shows, the Officer Basin remains a frontier basin for energy exploration with significant uncertainties due to data availability. Under the EFTF Officer–Musgrave Project, Geoscience Australia acquired new geomechanical rock property data from forty core samples in five legacy stratigraphic and petroleum exploration wells that intersected Paleozoic and Neoproterozoic aged intervals. These samples were subjected to unconfined compressive rock strength tests, Brazilian tensile strength tests and laboratory ultrasonic measurements. Petrophysical properties were also characterised via X-ray computerised tomography scanning, grain density and porosity-permeability analysis. Accurate characterisation of static geomechanical rock properties through laboratory testing is essential. In the modern exploration environment, these datasets are a precompetitive resource that can simplify investment decisions in prospective frontier regions such as the Officer Basin.

First Record of Oceanic Anoxic Event 1d at Southern High Latitudes: Sedimentary and Geochemical Evidence From International Ocean Discovery Program Expedition 369

AbstractOceanic anoxic event 1d (OAE 1d) has been well studied at northern low latitudes (i.e., in Tethys and the North Atlantic); however, the paleoenvironmental response to this event at high latitudes has not been documented and the triggering mechanism remains unknown. Here, we address both of these shortcomings by presenting the first detailed sedimentary and multi‐proxy geochemical record of the OAE 1d at southern high latitudes (60–62°S), obtained from sediments using Site U1513, IODP Expedition 369. Biostratigraphic and chemostratigraphic data support correlation of the interval studied with OAE 1d, and the sedimentary mercury proxy reveals that at least at Site U1513, OAE 1d is associated with the Central Kerguelen large igneous province volcanism. Furthermore, the significant increase in continental runoff and consequent terrigenous input from southwestern Australia in the southeastern proto‐India Ocean might have resulted in regionally weakened bottom‐water oxygenation and strengthened organic matter burial during OAE 1d.