Eyre Peninsula Of South Australia Research Articles

Thermochronological constraints on the tectonic history of the Polda Basin

The Polda Basin is a narrow, east–west striking intracontinental basin that extends ~400 km from the onshore Eyre Peninsula in South Australia to the offshore Great Australian Bight and contains up to 5 km of strata, with a thick sequence of Neoproterozoic rocks overlain by unconformably-bound sequences of Carboniferous-Permian, Jurassic and Cenozoic strata. Though the Polda Basin has witnessed limited exploration for hydrocarbons, it is attracting renewed interest due to the potential for underground hydrogen storage in Neoproterozoic halites, whilst surrounding regions of the Gawler Craton are considered prospective for natural hydrogen. To date however, knowledge of the tectonic history of the Polda Basin, which is critical to assessing its potential role in the energy transition, is limited. Here we present results from a regional apatite fission track analysis study of the Eyre Peninsula, focussing on data from the onshore Kilroo-1A borehole, which provide insights into the burial and exhumation history of the Polda Basin. Results indicate that the preserved Upper Jurassic sequence was thicker prior to Late Cretaceous exhumation, which may have supplied sediment to the adjacent Ceduna Sub-basin. Our results highlight a complex history of Phanerozoic vertical motions in this region, which have implications for both resource and energy storage potential.

Regenerative farming as climate action

Regenerative agriculture is an alternative approach to farming that has been gaining traction and interest among farmers due to its potential to reduce input costs, improve soil health, and increase the resilience of farming systems. This paper undertakes a practice-based analysis of farmers, applying a lens of regenerative agriculture. Surveys were developed as a part of a broader project using an established methodological framework. Topics were developed and adapted with input from local stakeholders before being mailed out to three farming regions across Australia (the Western Australian Wheatbelt, the Eyre Peninsula in South Australia and Central West New South Wales). The research clustered farmers into two groups: those who are using best-practices that fall inside the scope of regenerative agriculture, and those who are not. The similarities and differences in farmer attributes, as well as self-reported knowledge levels and information sources used by each group are explored. Results indicate that a belief in anthropogenic climate change may be one of the primary divides between the two groups, and therefore a possible driver of best-practice implementation. The findings provide insight into perceptions of regenerative agriculture for Australian farmers, and may assist with knowledge dissemination amongst those managing our environment.

Spatial genetic structure and limited gene flow in fragmented populations of the threatened Malleefowl (Leipoa ocellata)

The Malleefowl ( Leipoa ocellata ) is a threatened megapode bird that persists on the Eyre Peninsula of South Australia—an area that has undergone substantial clearance of native vegetation over the past 200 years. Habitat loss and fragmentation can negatively affect long-term conservation status by creating small and isolated subpopulations that lead to reduced gene flow, increased genetic drift, and inbreeding. In this study, we test whether Malleefowl on the Eyre Peninsula exhibit population structure that may have resulted from recent anthropogenic land cover changes. We used reduced-representation high-throughput DNA sequencing to obtain a dataset of 17,851 single nucleotide polymorphisms (SNPs). Our results suggest that Malleefowl are not genetically homogeneous across the Eyre Peninsula and that habitat fragmentation has likely driven differentiation of at least two distinct populations by decreasing opportunities for gene flow. We also provide preliminary genetic evidence for female-biased dispersal in Malleefowl. Our study highlights the potential problems caused by anthropogenic land cover changes for threatened Malleefowl populations and underscores the need for ongoing monitoring. We emphasise the importance of both large continuous native vegetation patches and small connecting habitat fragments even in highly fragmented landscapes. We encourage land managers to facilitate between-patch movement by improving native vegetation cover and controlling overabundant herbivores to improve habitat quality by allowing natural regrowth of existing native vegetation. • Habitat fragmentation has driven differentiation of Malleefowl populations on the Eyre Peninsula. • Preliminary genetic evidence for female-biased dispersal in a megapode. • Malleefowl management decisions should involve genetic targets. • Managers should facilitate between-patch gene flow by improving vegetation cover. • Lacking improvement, translocations may be necessary for better genetic health.

A Mineralisation Age for the Sediment-Hosted Blackbush Uranium Prospect, North-Eastern Eyre Peninsula, South Australia

The Blackbush uranium prospect (~12,580 tonnes U at 85 ppm cut-off) is located on the Eyre Peninsula of South Australia. Blackbush was discovered in 2007 and is currently the single example of sediment-hosted uranium mineralisation investigated in any detail in the Gawler Craton. Uranium is hosted within Eocene sandstones of the Kanaka Beds and, subordinately, within a massive saprolite derived from the subjacent Hiltaba-aged (~1585 Ma) granites, affiliated with the Samphire Pluton. Uranium is mainly present as coffinite in different lithologies, mineralisation styles and mineral associations. In the sandstone and saprolite, coffinite occurs intergrown with framboidal Fe-sulphides and lignite, as well as coatings around, and filling fractures within, grains of quartz. Microprobe U–Pb dating of coffinite hosted in sedimentary units yielded a narrow age range, with a weighted average of 16.98 ± 0.16 Ma (343 individual analyses), strongly indicating a single coffinite-forming event at that time. Coffinite in subjacent saprolite generated a broader age range from 28 Ma to 20 Ma. Vein-hosted coffinite yielded similar ages (from 12 to 25 Ma), albeit with a greater range. Uraninite in the vein is distinctly older (42 to 38 Ma). The 17 ± 0.16 Ma age for sandstone-hosted mineralisation roughly coincides with tectonic movement as indicated by the presence of horst and graben structures in the Eocene sedimentary rocks hosting uranium mineralisation but not in stratigraphically younger sedimentary rocks. The new ages for hydrothermal minerals support a conceptual genetic model in which uranium was initially sourced from granite bedrock, then pre-concentrated into veins within that granite, and is subsequently dissolved and reprecipitated as coffinite in younger sediments as a result of low-temperature hydrothermal activity associated with tectonic events during the Tertiary. The ages obtained here for uranium minerals within the different lithologies in the Blackbush prospect support a conceptual genetic model in which tectonic movement along the reactivated Roopena Fault, which triggered the flow of U-rich fluids into the cover sequence. The timing of mineralisation provides information that can help optimise exploration programs for analogous uranium resources within shallow buried sediments across the region. The model presented here can be predicted to apply to sediment-hosted U-mineralisation in cratons elsewhere.

Are we ready for bushfire? Perceptions of residents, landowners and fire authorities on Lower Eyre Peninsula, South Australia

Housing developments on the peri-urban fringe of Australian towns and cities create complexities for bushfire management due to the intermingling of natural, rural and urban spaces. To address the risk of bushfire, policies and practices have promoted and encouraged landowner responsibility for bushfire mitigation actions and behaviours. Using a postal survey, interviews and focus groups, we examine perceptions and actions regarding bushfire preparedness from the viewpoints of individual residents, landowners, and the local fire and environmental authorities on the Lower Eyre Peninsula of South Australia. Respondents living on larger sized allotments were more likely to perceive that their property was vulnerable to bushfire than those living on residential-sized allotments. Larger holdings tend to have more fire-susceptible vegetation than the smaller properties located in fringe suburbs, which seems to confer to those latter residents a sense of greater safety from bushfires. On the other hand, residents on larger blocks reported higher levels of bushfire management knowledge and expressed stronger connections to the place where they live, which influenced their willingness to work to mitigate bushfire risk. Importantly, there is a disconnection between such individual landholder preparedness for bushfire and that of the broader community. Individual actions often do not translate into collective responses, suggesting that a greater sense of shared responsibility will need to develop to enable effective mitigation of regional bushfire risk at a regional scale.

Spatial variability of chloride deposition in a vegetated coastal area: Implications for groundwater recharge estimation

Summary Knowledge of atmospheric chloride deposition is a prerequisite for applying the chloride mass balance (CMB) method for groundwater recharge estimation. Compared to bare areas, vegetated areas can significantly enhance chloride deposition rates as the vegetation canopy provides a large surface onto which water droplets and aerosols settle. Although generally acknowledged, this effect has often been ignored in practical applications of the CMB method. This paper studies the variability of chloride deposition in a coastal basin characterised by a heterogeneous vegetation cover, and the implications of this variability for groundwater recharge estimation using observation wells in the saturated zone. The study area is located on the Eyre Peninsula in South Australia. The theory of the CMB method for groundwater recharge estimation is revised in the context of highly spatially variable chloride deposition. A GIS-based approach is developed for mapping the chloride deposition accounting for distance from the coast, distribution of vegetation and edge effects; the latter implying a lower chloride deposition inside a vegetation stand than at the edge. In order to quantify the significance of one or several of these effects for recharge estimation, different chloride deposition maps and corresponding recharge estimates are derived. Compared with the reference scenario that accounts for all effects, neglecting the coastal effect results in a 33–36% higher average recharge estimate, whereas neglecting the vegetation effect results in a 17–22% lower average recharge estimate. The latter numbers are likely to represent a lower bound of the impact of neglecting the vegetation effect. A critical factor for accurate determination of the influence of vegetation appears to be the edge effect, albeit its importance is subject to significant uncertainty that warrants further monitoring.

Plant growth responses to biochar addition: an Australian soils perspective

The use of biochar as an agricultural amendment has attracted much attention owing to its potential to improve soil condition and plant growth; however, production outcomes are often uncertain. Although soil type is a major driver of plant productivity, there are relatively few biochar studies that directly compare plant growth responses across a range of soil types. We tested the wheat growth response to biochar derived from poultry litter and from wheat straw applied at 1, 5 and 10 t ha−1 (approximately 0.13, 0.67 and 1.33 % w/w) in four soils representing major agricultural regions in Australia: an acidic arenosol (Western Australian cereal belt), an acidic rhodic ferralsol (Northern New South Wales), a neutral vertisol (Queensland cropping) and an alkaline haplic calcisol (Eyre Peninsula in South Australia). In the neutral vertisol, where plant growth was vigorous in the control treatments, biochar had little impact, whereas in the alkaline calcisol, there was a small significant increase in shoot biomass at high (10 t ha−1) application rates. Plant growth responses in the acidic soils were most evident but demonstrated a strong contrast to one another. In the acidic arenosol, negative growth impact correlated with increasing electrical conductivity, while in the acidic ferralsol a small rate-dependent increase in pH correlated with relatively large gains in biomass, possibly due to improved phosphorus nutrition and alleviated Al toxicity. Moving towards effective integration of biochar as a management tool will not only require stratification based on soil types, but wider consideration of the main plant production constraints, such as pH, pertinent to a particular system.

Combining management based indices with environmental parameters to explain regional variation in soil carbon under dryland cropping in South Australia

Identifying drivers of variation in soil organic carbon (OC) at a regional scale is often hampered by a lack of historical management information. Focusing on red-brown-earth soils (Chromosol) under dryland agriculture in the Mid-North and Eyre Peninsula of South Australia, our aims were 2-fold: (i) to provide a baseline of soil OC stocks (0.3 m) and OC fractions (mid-infrared predictions of particulate, humus, and resistant OC in 0.1 m samples) in cropping and crop-pasture systems; and (ii) to evaluate whether the inclusion of management-based indices could assist in explaining regional-level variation in OC stocks and fractions. Soil OC stocks in both regions varied ~20 Mg ha–1, with higher OC stocks in the Mid-North (38 Mg ha–1) than the Eyre Peninsula (29.1 Mg ha–1). The humus OC fraction was the dominant fraction, while the particulate OC was the most variable. Environmental variables only partially explained soil OC variability, with vapour pressure deficit (VPD) offering the greatest potential and likely acting as an integrator of temperature and moisture on plant growth and decomposition processes. Differences between broad-scale cropping and crop–pasture systems were limited. In the Mid-North, variability in soil OC stocks and fractions was high, and could not be explained by environmental or management variables. Higher soil OC concentrations (0.1 m) in the Eyre Peninsula cropping than crop–pasture soils were largely accounted for in the particulate OC fraction and are therefore unlikely to represent a long-term stable OC pool. Use of the management data in index format added some explanatory power to the variability in OC stocks over the main environmental variables (VPD, slope) within the Eyre Peninsula cropping soils only. In the wider context, the management data were useful in interpreting differences between regional findings and highlighted difficulties in using uninformed, broad-scale management categories.

New Species and new Records of the Genus Anomotarus Chaudoir from Australia. 2ND Supplement to the ‘Revisions of the Species of the Genus Anomotarus Chaudoir’ (Insecta, Coleoptera, Carabidae, Lebiini)

New species and new records of the genus Anomotarus Chaudoir from Australia. 2nd supplement to the ‘revisions of the species of the genus Anomotarus Chaudoir’.Three additional new species of the lebiine genus Anomotarus Chaudoir, subgenus Anomotarus, and one species of the subgenus Nototarus Chaudoir are described from Australia and Tasmania: Anomotarus (s. str.) moorei from Australian Capital Territory, A. (s. str.) kimberleyensis from far northern Western Australia, A. (s. str.) sericipennis from Tasmania, and A. (Nototarus) eyrensis from the Eyre Peninsula in south Australia. The new species are introduced in the most recent keys to the Australian species of the genus Anomotarus (s. l.). new records of some rare or recently described species of the subgenera Anomotarus s. str., Nototarus Chaudoir, and Amplitarus Baehr are communicated.

To catch a starling: testing the effectiveness of different trap and lure types

Context Worldwide, invasive fauna species present one of the most intractable problems for agriculture and natural systems. Our ability to improve control techniques to combat the global invasive species predicament is constrained within the bounds of both economic and ethical considerations. In south-eastern Australia, the common starling (Sturnus vulgaris) is an established invasive avian pest that is now making incursions into areas of Western Australia (WA) that are currently free of this species. The most cost-effective and widely implemented starling control tool is trapping with live-lure birds. In recent years, the use of live-lure birds has been questioned on both economic and ethical grounds, and consequently alternative lure methods need investigating. Aims To evaluate the effectiveness of different trap and lure combinations for the capture of starlings in western South Australia (SA). Methods Modified Australian Crow (MAC) traps, used traditionally in WA to trap starlings, and Myna traps, originally designed for trapping common mynas (Sturnus tristis), were set during the peaks in starling flocking activity (Austral summer, 2007) using three different lure types: (1) live lure (live starlings); (2) moving water; and (3) acoustic lures. A trapping grid consisting of a single Myna trap with live lure and three MAC traps, each with one type of lure (live, water or acoustic) was established at five sites on the Eyre Peninsula in SA and monitored twice daily for 28 days. Key results Live lures were significantly more effective at attracting starlings into traps compared with both water and sound lures. We also trapped at an additional three sites and showed that Myna traps caught ~1.5 times more starlings than MAC traps when both traps were fitted with live-lure birds. Conclusions Neither moving water nor acoustic play-back lures proved suitable replacements for the use of live-lure birds to capture starlings. The efficacy of alternative lure types may depend on several factors and may include neophobic response(s) to novel signals and also the length of time that an invasive population has been established. Implications We recommend that use of live lures is continued in ongoing starling control programs, and that MAC traps currently in use be modified to capitalise on known starling behaviour. Further research and development of traps that do not contain live lures will improve the welfare of invasive species control programs.

Bushfire impact on youth

The authors examined the association between disaster-related traumatic experiences and posttraumatic stress disorder (PTSD) symptoms in 155 youth, aged 8-18 years, from the Lower Eyre Peninsula of South Australia who were affected by January 2005 bushfires. Youth completed measures of PTSD symptoms and disaster experiences 11-5 months postdisaster. Many youth (27%) reported moderate to severe levels of PTSD symptoms; younger children reported greater PTSD symptom severity than older youth. Perceived personal life threat and ongoing loss/disruption were related to greater PTSD symptomatology. Following disasters, it may be helpful to identify young children and youth who perceived that their life was threatened and experienced more ongoing life disruption, as these youth may be at higher risk for persistent PTSD symptoms.

Impact of subsoil physicochemical constraints on crops grown in the Wimmera and Mallee is reduced during dry seasonal conditions

Subsoil physicochemical constraints can limit crop production on alkaline soils of south-eastern Australia. Fifteen farmer paddocks sown to a range of crops including canola, lentil, wheat, and barley in the Wimmera and Mallee of Victoria and the mid-north and Eyre Peninsula of South Australia were monitored from 2003 to 2006 to define the relationship between key abiotic/edaphic factors and crop growth. The soils were a combination of Calcarosol and Vertosol profiles, most of which had saline and sodic subsoils. There were significant correlations between ECe and Cl– (r = 0.90), ESP and B (r = 0.82), ESP and ECe (r = 0.79), and ESP and Cl– (r = 0.73). The seasons monitored had dry pre-cropping conditions and large variations in spring rainfall in the period around flowering. At sowing, the available soil water to a depth of 1.2 m (θa) averaged 3 mm for paddocks sown to lentils, 28 mm for barley, 44 mm for wheat, and 92 mm for canola. Subsoil constraints affected canola and lentil crops but not wheat or barley. For lentil crops, yield variation was largely explained by growing season rainfall (GSR) and θa in the shallow subsoil (0.10–0.60 m). Salinity in this soil layer affected lentil crops through reduced water extraction and decreased yields where ECe exceeded 2.2 dS/m. For canola crops, GSR and θa in the shallow (0.10–0.60 m) and deep (0.60–1.20 m) layers were important factors explaining yield variation. Sodicity (measured as ESP) in the deep subsoil (0.80–1.00 m) reduced canola growth where ESP exceeded 16%, corresponding to a 500 kg/ha yield penalty. For cereal crops, rainfall in the month around anthesis was the most important factor explaining grain yield, due to the large variation in rainfall during October combined with the determinant nature of these crops. For wheat, θa in the shallow subsoil (0.10–0.60 m) at sowing was also an important factor explaining yield variation. Subsoil constraints had no impact on cereal yield in this study, which is attributed to the lack of available soil water at depth, and the crops’ tolerance of the physicochemical conditions encountered in the shallow subsoil, where plant-available water was more likely to occur. Continuing dry seasonal conditions may mean that the opportunity to recharge soil water in the deeper subsoil, under continuous cropping systems, is increasingly remote. Constraints in the deep subsoil are therefore likely to have reduced impact on cereals under these conditions, and it is the management of water supply, from GSR and accrued soil water, in the shallow subsoil that will be increasingly critical in determining crop yields in the future.

Population structure, flowering and seed production in the endangered Whibley wattle, Acacia whibleyana (Leguminosae: Mimosoideae).

Acacia whibleyana (Whibley wattle) is a nationally endangered wattle, endemic to the near-coastal region around Tumby Bay on the Eyre Peninsula in South Australia. Two distinct sub-populations, referred to as the Quarry and the Salt-lake populations, each contained plants growing on roadsides and in scrub fragments. Marked differences were observed in the population size structure between the two populations. The absence of juveniles on roadsides in both populations signaled potential limitations to natural recruitment. Studies of reproductive biology of scrub plants over two years (1996-1997) indicated that between 1.1% (Salt-lake) and 6.9% (Quarry) of A. whibleyana inflorescences produced fruit. Each infructescence produced an average of 1.2-1.8 pods, although up to 10 pods per infructescence were observed at the Quarry scrub in 1996. Each pod contained 4-6 seed on average, with a viability of 85%. Plants at the Salt-lake scrub generally set less fruit, produced fewer pods per infructescence, and had lower seed numbers per pod when compared with Quarry plants, differences attributable to the superior vigor of Quarry plants. A. whibleyana seeds were dispersed by ants attracted by the lipid-rich aril. The soil seed bank had a patchy distribution across both sites possibly due to seed concen- trating in the vicinity of ant nests. We concluded that the reproductive attributes studied were unlikely to constrain natural recruitment of A. whibleyana as both populations were capable of producing viable seed over the two years of this study.

Investigation on the groundwater resources of the South Eyre Peninsula, South Australia, determined from laterally constrained inversion of tempest data

Groundwater in the Eyre Peninsula of South Australia is scarce with potable resources limited to the western coastal margin and the southern tip of the peninsula. Consequently an understanding of their extent has become increasingly important particularly with demand being close to current extraction limits. In September 2006, about 1000 line km of TEMPEST AEM data were acquired over the Southern Eyre Peninsula, in order to assist in the definition of freshwater lens systems and in particular aquifer bounds associated with them as part of a resource definition project. Following their acquisition, the TEMPEST data set was analysed for data quality and then transformed into conductivity depth images (CDI) using EMFLOW and subsequently using a smooth model inversion (see Fitzpatrick and Munday, 2007). In an effort to better define to better define the geometry of specific bounding surfaces of hydrogeological relevance the TEMPEST data were inverted through the application of the laterally constrained inversion (LCI) technique. This paper describes the initial results from the first application of the LCI to data from a fixed wing AEM system.

On community capitals as we see them through photovoice: Cowell oyster industry in South Australia

In this article, we discuss a photovoice study of the oyster industry in Cowell on the Eyre Peninsula in South Australia. For the last 15 years the Cowell community has been adding water-based farming – the environmentally sensitive industry of oyster aquaculture - to its land-based farming. The community capitals approach for assessing community sustainability was undertaken using photovoice and a photo stimulated workshop. Whilst this study provides data on natural, produced, and institutional capitals, the method enabled subtle reflections to be made on social and human capitals. Hence it provides some data on these hard to capture aspects of the capitals approach. The method allowed the Cowell community to tell their insider-looking- out story of the impact of oyster aquaculture on their community. The capitals approach linked well with photovoice methodology, and would have wider applicability in assessing the impact of other environmentally sensitive industries and developments in other communities. Findings from the study indicated that oyster aquaculture is viewed by Cowell community members as adding positive social and human capital, and that any negative aspects of the industry on the other capitals are seen as minor.

Applications of Metribuzin for The Control of Rigid Brome (Bromus rigidus) in No-Till Barley Crops of Southern Australia

Field experiments were conducted at Warooka and Rudall on the Yorke and Eyre Peninsula of South Australia during 2004 and 2005 to investigate the effectiveness of metribuzin for the selective control of rigid brome in no-till sown barley. Metribuzin (135 to 203 g ai/ha) incorporated by sowing (IBS) was more effective in controlling rigid brome (> 67%) than the same herbicide dose applied POST. Although IBS metribuzin at the highest rate (270 g/ha) provided effective weed control (82 to 90%), it was more phytotoxic to barley, reducing crop density by 23% relative to the nontreated control at Rudall. Soil at Rudall had low clay and organic matter content. In contrast, tank mixtures of metribuzin (203 g/ha) with pendimethalin, applied IBS, provided reliable rigid brome control (89 to 93%) and resulted in little crop damage (< 5%). Over the site-by-year combinations studied, all herbicide-treated barley at Warooka and Rudall yielded 6 to 50% more grain than the nontreated crop. Although metribuzin provides growers with an opportunity to selectively control rigid brome in no-till barley, high rates (≥ 203 g/ha) of this herbicide on sandy textured soils can result in significant crop damage.Nomenclature: Metribuzin, rigid brome, Bromus rigidus Roth BRORI, barley, Hordeum vulgare L

Abundance and distribution of South Australia's endemic sea star, Parvulastra parvivipara (Asteroidea: Asterinidae)

Parvulastra parvivipara is one of the smallest sea stars. It is restricted to tide pools on seven granite platforms within 200 km of coastline on the Eyre Peninsula of South Australia. This species exhibits intragonadal brooding and cannibalism of offspring, and gives birth to non-dispersive juveniles. Its distribution is variable, with specimens occupying few of the many seemingly similar tide pools at each site at differing densities. The abundance and distribution of P. parvivipara were examined in relation to twelve ecological variables of tide pools at all known mainland sites. An estimate of overall population size was also made. Multiple regression analyses showed that the abundance of P. parvivipara was negatively associated with wave-exposure and positively associated with the structural complexity of tide pools. A multiple logistic regression also indicated that the presence of sea stars (distribution) was more likely in structurally complex tide pools with low wave-exposure. Additionally, increasing elevation of a tide pool relative to the high-tide margin within the intertidal zone reduced the likelihood of finding sea stars. It is suggested that the variable abundance and distribution of P. parvivipara may be driven by broad scale ecological variables (e.g. complexity and wave-exposure), localised population extinctions (within tide pools) and recolonisation of tide pools via transportation of individuals across the rock platforms by wave-energy. It is also suggested that strikingly high abundances of P. parvivipara in some tide pools are likely to result from the reproductive mode of this species where each hermaphroditic individual gives birth to cohorts of up to twenty non-dispersive juveniles.

High resolution provenancing of long travelled dust deposited on the Southern Alps, New Zealand

On 7 February 2000 an atypical orange discolouration of snowfields in the central Southern Alps, New Zealand occurred following the passage of a cold front. Analysis of snow samples identified fine orangey-brown dust mixed with much coarser grey dust. Air parcel forward trajectories from dust sources in southern and central Australia, where dust storms were reported on 4 February 2000, were computed to identify the deposits source. Geochemical analyses of the dust deposit using 26 trace elements, unaffected by regional air pollution and gravitational sorting, indicate that 20% of the dust was sourced from western New South Wales, with 45% from the eastern Eyre Peninsula of South Australia and the remaining 35% was local New Zealand dust. This provenancing approach provides a spatial resolution of long travelled dust sourcing not previously achieved.

A new species of Commersonia (Malvaceae s.l.) from the Eyre Peninsula, South Australia

Commersonia multiloba C.F.Wilkins & Whitlock is described as new and illustrated. It is restricted in distribution and apparently confined to two populations on the northern Eyre Peninsula in South Australia and regarded as a species with special conservation needs.

Habitat specificity, seed germination and experimental translocation of the endangered herb Brachycome muelleri (Asteraceae)

Brachycome muelleri Sonder (Corunna daisy) is an endangered annual herb, endemic to the upper Eyre Peninsula of South Australia. It is restricted to a single population occupying an area of approximately 3 ha on steep, south-facing cliff-foot slopes of the Baxter Hills. Its unique habitat, within an otherwise generally arid region, optimises soil moisture retention through the provision of concentrated water catchment, shade, and low evaporation rates during the growing season. Weeds had the potential to significantly disrupt recruitment, growth and reproductive output, but grazing did not constitute a direct threat to the population. Fresh seeds were innately dormant, requiring a period of after-ripening before they would germinate. Dormancy was artificially broken by gibberellic acid (GA 3) treatment. Germination was optimal at 20 °C, and it was proposed that temperature plays an important role in regulating germination in situ. B. muelleri seeds did not respond to smoked water treatment, and GA 3 (1000 mg l −1) was recommended as a routine seed treatment to stimulate germination. Trial translocations using seed as founder propagules resulted in low establishment, growth and flowering rates. Established seedlings provided several advantages over seed as founder propagules, including higher success rates, more vigorous growth, and improved seed yields in the first season. Successful regeneration, proliferation and expansion of a new translocated population was observed and recorded over four consecutive years. We suggest that conservation management of this species should include the establishment of several new populations by translocation to suitable, isolated, weed-free sites.