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Golden everlasting paper daisies in the genus Xerochrysum Tzvelev are iconic Australian native plants grown worldwide. The X. bracteatum species complex has been regarded as taxonomically confusing and in need of revision for over 60 years. We applied morphological and molecular analyses to delimit species, detect common ancestry among populations, and identify putative hybrids in the genus Xerochrysum (Asteraceae: Gnaphalieae). Multiple lines of evidence provided strong support for the recognition of new taxa. Here we describe the following 11 new species: X. andrewiae T.L.Collins & J.J.Bruhl, X. berarngutta T.L.Collins & I.Telford, X. copelandii J.J.Bruhl & I.Telford, X. frutescens J.J.Bruhl & I.Telford, X. gudang T.L.Collins & J.J.Bruhl, X. hispidum T.L.Collins & I.Telford, X. macsweeneyorum T.L.Collins, X. murapan T.L.Collins & I.Telford, X. neoanglicum J.J.Bruhl & I.Telford, X. strictum T.L.Collins, and X. wilsonii T.L.Collins, reinstate Helichrysum banksii A.Cunn. ex DC. (as X. banksii (A.Cunn. ex DC.) T.L.Collins & I.Telford), lectotypify X. banksii and X. papillosum (Labill.) R.J.Bayer, and recircumscribe X. bicolor (Lindl.) R.J.Bayer to include X. halmaturorum Paul G.Wilson and some populations of X. bracteatum sens. lat. from mainland South Australia and Victoria. We also provide revised descriptions of all taxa in the genus, their conservation status, a dichotomous key, tables distinguishing closely related taxa and distribution maps. Golden everlasting paper daisies in the genus Xerochrysum are iconic Australian native plants grown worldwide, but have been in need of revision for over 60 years. We use multiple lines of evidence to delimit species, detect common ancestry among populations and identify putative hybrids. We describe 11 new species, provide revised descriptions, conservation status, a dichotomous key, tables distinguishing closely related taxa, and distribution maps. [ABSTRACT FROM AUTHOR]

The potential link between certified organic farming and biodiversity and conservation remains unexplored in Australia, despite the country having the world's largest amount of certified organic farmland and unprecedented biodiversity loss. This study modelled the spatial effects of organic farming (intensity of local farming systems), environmental heterogeneity, and urbanisation on two widely studied environmental taxa - vascular plant and bird species richness (surrogate measures of biodiversity) - in South Australia, using a unique certified organic farming postcode level dataset from 2001 to 2016 (N = 5440). The spatial Durbin error model results confirmed the positive spatial congruence of organic farming with greater vascular plant species richness, whereas only weak to no significant evidence was found for bird species richness. Landscape features (habitat heterogeneity) and green vegetation (a proxy indicator of resource availability) - rather than organic farming - appeared to be most associated with bird species richness. Both plant and bird species richness were positively associated with habitat heterogeneity (land cover diversity and elevation range), plant productivity and proportion of conservation land and water bodies. Whereas, increased anthropogenic land use for cropping and horticultural farming, soil type diversity and proximity to the coast significantly reduced species richness of both taxa. The results suggest that a multi-scale spatially refined biodiversity conservation strategy, with spatial targeting that promotes low intensive farming systems and increases landscape heterogeneity to provide quality habitat (a whole of landscape approach by incorporating private agricultural landholders), could be beneficial for biodiversity conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2022. Published by Elsevier Ltd. All rights reserved.)

The implementation of rangeland biodiversity management strategies relies on the engagement and participation of key stakeholders, including local pastoralists (ranchers). Understanding pastoralists' knowledge of biodiversity, as well as their attitudes towards and perceptions of biodiversity management strategies, is fundamental for the development of efficacious rangeland management. This paper examines perceptions of biodiversity and land management strategies held by pastoralists in the Stony Plains region (SPR) of South Australia and reports on a survey, consisting of 45 questions, delivered to lessees and/or managers of pastoral leases within or on the edge of the SPR. Respondents generally agreed with prescribed land management strategies, but agreement did not mean that strategies were being implemented. The purchase of pastoral leases by government and/or conservation groups for biodiversity purposes was opposed strongly, which may present a barrier to collaborative land management. Pastoralists strongly agreed with several listed threats to biodiversity, but their feelings on climate-related threats were less strong. Attitudes to climate may have been influenced by above-average rainfall experienced during and preceding the survey period and by the climatic variability that characterises arid rangelands. Biodiversity conservation and the pastoral industry rely on collaborative rangeland management, non-bureaucratic communication, and an understanding among stakeholders of the attitudes and perceptions of other natural-resource users., (Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.)

In the growing field of Geoheritage, Geoconservation, Geo-education and Geotourism, there is a need to manage sites of geoheritage significance. While there is some great geology in nature available to appreciate for scenic value, education, tourism and research, many locations need to be protected from people and commercialism (e.g. the Iridium layer at the K/T boundary in Gubbio, Italy, the Ediacaran fauna in South Australia, the Burgess Shale in Canada or the zircon crystals at Jack Hills, among many others), and some locations need hazard management to protect people (e.g. continuously collapsing cliffs that have potential to be hazardous via rock falls, or slippery slopes, or high cliffs that are treacherous, or 'king waves' on rocky shores). The concept of the '8Gs' is intended as a policy-style guidance that logically and progressively links Geology and Geoheritage through a series of steps to Geo-education and Geotourism. There is a logical progression from Geology the Science, through to Geoheritage and the identification of sites of geoheritage significance, to the establishment of Geosites/Geoparks, Geoconservation, leading to Geomanagement, Geo-education and Geotourism. Geomanagement needs to be undertaken prior to the use of sites for Geo-education and Geotourism. In relation to Geomanagement, sites need to be investigated for safety issues, and for the protection of their geological features. Geodiversity, the eighth 'G', is outside the progression but plays an important part in underpinning biodiversity. There is also a need to address and manage geodiversity in a given region or specific site to help understand and manage biodiversity. [ABSTRACT FROM AUTHOR]

In Australia, the deep-water (bathyal and abyssal) benthic invertebrate fauna is poorly known in comparison with that of shallow (subtidal and shelf ) habitats. Benthic fauna from the deep eastern Australian margin was sampled systematically for the first time during 2017 RV 'Investigator' voyage 'Sampling the Abyss'. Box core, Brenke sledge, and beam trawl samples were collected at one-degree intervals from Tasmania, 42°S, to southern Queensland, 24°S, from 900 to 4800 m depth. Annelids collected were identified by taxonomic experts on individual families around the world. A complete list of all identified species is presented, accompanied with brief morphological diagnoses, taxonomic remarks, and colour images. A total of more than 6000 annelid specimens consisting of 50 families (47 Polychaeta, one Echiura, two Sipuncula) and 214 species were recovered. Twenty-seven species were given valid names, 45 were assigned the qualifier cf., 87 the qualifier sp., and 55 species were considered new to science. Geographical ranges of 16 morphospecies extended along the eastern Australian margin to the Great Australian Bight, South Australia; however, these ranges need to be confirmed with genetic data. This work providing critical baseline biodiversity data on an important group of benthic invertebrates from a virtually unknown region of the world's ocean will act as a springboard for future taxonomic and biogeographic studies in the area. [ABSTRACT FROM AUTHOR]

It is unequivocal that the poor condition of South Australia's terrestrial biodiversity is continuing to decline overall - much like elsewhere in Australia. This decline is mainly due to the legacy of vegetation clearing and habitat modification since European colonisation, the destructive influence of invasive species (especially predators like cats and foxes) on its native fauna and flora, and impotent or broken legislation to prevent further damage. The struggle to maintain our remaining biodiversity, and our intentions to restore once-healthy ecosystems, are rendered even more difficult by the added influence of rapid climate disruption. Despite the pessimistic outlook, South Australians have successfully employed several effective conservation mechanisms, including increasing the coverage of our network of protected areas, doing ecological restoration projects, reducing the densities of feral animals across landscapes, encouraging private landholders to protect their biodiversity assets, releasing environmental water flows to rivers and wetlands, and bringing more people in touch with nature. While these strategies are certainly stepping in the right direction, our policies and conservation targets have been hampered by arbitrary baselines, a lack of cohesion among projects and associated legislation, unrepresentative protected areas, and inappropriate spatial and time scales of intervention. While the challenges are many, there are several tractable and affordable actions that can be taken immediately to improve the prospect of the State's biodiversity into the near future. These include coordinating existing and promoting broader-scale ecological restoration projects, establishing strategic and evidence-based control of invasive species, planning more representative protected-area networks that are managed effectively for conservation outcomes, fixing broken environmental legislation, avoiding or severely limiting biodiversity-offset incentives, expanding conservation covenants on private land, coordinating a state-wide monitoring network and protocol that tells the South Australian community how effective we are with our policies and actions, expanding existing conservation investment and tapping into different funding schemes, and coordinating better communication and interaction among government and non-governmental environment agencies. Having a more transparent and defensible link between specific conservation actions and targeted outcomes will also likely improve confidence that conservation investments are well-spent. With just a little more effort, coordination, funding, and foresight, South Australia has the opportunity to become a pillar of biodiversity conservation. [ABSTRACT FROM AUTHOR]

Striking a balance between the management of environmental risks and values is a challenge for decision-makers. If people perceive that environmental risks are increasing they may be willing to discount local values to manage those risks, so the identification of thresholds in risk perception in relation to specific behaviors could help to avoid policy failures. The complex relationships between perceptions of climate change and bushfire risks, environmental values and support for actions to mitigate local risks are presented for peri-urban regions in South Australia. The results of a household survey (N=988) suggest that a threshold of risk perception in relation to climate change and bushfire management has not been exceeded and people are broadly supportive of balanced management interventions. A minority of people still do not perceive that climate change is increasing bushfire risk, and are supportive of risk mitigation interventions even at the expense of local biodiversity. However, a larger group believe that climate change is a driver of bushfire risk, yet are still more likely to prioritize ecological values and are unwilling to discount those values for risk mitigation. Targeted communication could assist different groups to respond to gaps in knowledge and action to facilitate effective, differentiated interventions within forested landscapes on the margins of urban areas. [ABSTRACT FROM AUTHOR]

Earth is currently experiencing the sixth mass extinction of complex multi-cellular life, the first at the hands of a single species. The documented extinctions of iconic (mostly vertebrate and plant) taxa dominate the discourse, while poorly known invertebrate species are disappearing 'silently', sometimes without having ever been described. Here, we highlight the decline of elements of the trapdoor spider (Mygalomorphae: Idiopidae) fauna of southern Australia - a taxonomically poorly documented yet diverse assemblage of long-lived fossorial predators. We show that a number of trapdoor spider species may be threatened after a century of intensive land clearing and stocking, and that remaining populations in some areas may be experiencing serious contemporary population declines. So, how do we conserve this fauna? We suggest that baseline systematic studies are crucial, and that follow-up surveys, including integrative citizen science solutions, should be used to assess where remnant populations still exist, and whether they can persist into the future. Detailed population genetic research on a handful of carefully chosen taxa could be broadly informative, and ongoing natural history studies remain invaluable. Although solutions may be limited in the face of ongoing habitat degradation and other threats, urgently quantifying declines has implications not just for spiders but for mitigating against the mass extinction of poorly known invertebrate taxa across the globe. [ABSTRACT FROM AUTHOR]

Submarine canyons are known to play an important role in enhancing productivity in adjacent surface waters, but their influence on the seabed fauna is poorly understood. Here we examine environmental conditions in two canyons with contrasting topographies, and evaluate their relative importance in structuring benthic megafaunal assemblages. Samples of benthic megafauna, sediment and water were collected from five sites at du Couedic Canyon (100–1500 m) and six sites at Bonney Canyon (100–2000 m) off South Australia. Sessile suspension-feeding organisms (primarily sponges, molluscs and cnidarians) dominated samples and comprised 97% of the biomass and 77% of the total species richness (184 spp.). Megabenthic biomass and species richness broadly declined with increasing depth in both canyons, but was markedly higher at du Couedic Canyon in an area subject to organically enriched seasonal outflows from Spencer Gulf. Multivariate analyses showed a strong environmental gradient running perpendicular to the coast in both canyons, and highlighted a progressive shift in species composition. Three station groupings were identified on the shelf (100–200 m), upper slope (500 m) and mid slope (1000–2000 m). These community groupings were largely explained by depth and dissolved oxygen concentration and coincided with depth-related discontinuities in water masses on Australia's southern continental margin. [ABSTRACT FROM AUTHOR]

Abstract: The SeaWiFS data set covering the period 1997–2007 is used to develop a framework for a comprehensive description of the inter-annual variations in chlorophyll a concentration (Chla). For each grid cell, the monthly Chla series is decomposed into seasonal, irregular and trend-cycle terms with the Census X-11 technique that is an iterative band-pass filter algorithm. This approach allows variations in the annual cycle, while the trend-term isolates the multi-annual evolution in the mean level of the signal. The patterns with relatively large inter-annual variations are selected using the variance due to the trend-term with respect to the total variance, and are compared with maps of monotonic trends derived by a non-parametric Kendall analysis. Most of these patterns are identified in the subtropical domain (30°S–30°N), even though there are patterns with strong variations at mid-latitudes, particularly in the Northeast Atlantic and South of Australia. The time series found within each pattern of interest are found coherent. Conversely, the ensemble of spatially averaged time series of Chla trend-terms shows a diversity of evolutions, with rather monotonic changes for all or part of the period, abrupt shifts or low-frequency oscillations, sometimes coupled with a modification in the amplitude of the annual cycle. Some of these series are correlated with climate indices, and those in subtropical regions usually show a negative correlation with the equivalent trend-term calculated for sea surface temperature. The identified inter-annual signals should be further monitored with longer time series and can serve as test cases for biogeochemical models. [Copyright &y& Elsevier]

While exceptionally diverse fossil assemblages of non-biomineralised organisms (Lagerstatten) are rare, they are unusually common in marine sedimentary sequences of early and mid-Cambrian age. Their mode of preservation has been the subject of much debate. The lower Cambrian (Series 2) Emu Bay Shale biota, found at Big Gully on the north coast of Kangaroo Island, is by far the richest Burgess Shale-type (BST) fauna known in the southern hemisphere. Such fauna are preserved characteristically as two-dimensional compression fossils, comprising both carbonaceous and mineralised films on bedding surfaces of the host marine mudstones. The biotic diversity of the Big Gully assemblage suggests a habitat very favourable for life. Its preservation is exceptional, with gut remains and other soft parts quite common. Evidence of predation and scavenging is rare, and the finely laminated texture of the host mudstone attests to a lack of burrowing and bioturbation. Recent studies indicate that conservation of organic tissues, rather than authigenic mineralisation of their more labile components, is the principal taphonomic pathway responsible for BST deposits. In so far as such preservation requires suppression of the early diagenetic processes that normally result in the rapid decay of organic matter at or near the sea floor, the oxicity of the bottom waters, below which the Emu Bay Shale accumulated, becomes critically important. Here we determine the paleoredox status of the fossiliferous basal portion of the formation using selected trace element proxies, in combination with total organic carbon (TOC) concentrations and isotopic signatures (δ13Corg). We also establish its degree of thermal alteration as a datum for use in taphonomic comparisons with other Cambrian Lagerstatten. The Emu Bay Shale contains insufficient organic matter (TOC = 0.25-0.55%) to have accumulated under stable anoxic conditions. Even allowing for the inevitable loss of organic carbon during the oil- and gas-generation phases of thermal maturation, to a present rank equivalent to ∼1.5% vitrinite reflectance, its original TOC content was <1%. Measurement of a series of redox-sensitive elemental ratios (viz. U/Th, V/Cr, Ni/Co and V/Sc) across the lower 8 m-thick fossiliferous section of the Emu Bay Shale confirms that it was deposited beneath an oxic water column. In this respect it is similar to the archetypical Burgess Shale. In the absence of an exaerobic zone, benthic cyanobacterial mats are likely to have mantled recently dead fauna and helped maintain the integrity of a sharp redox boundary at the sediment-water interface. [ABSTRACT FROM AUTHOR]

This study examines spatially referenced perceived landscape values and climate change risks collected through public participation geographic information systems for potential use in climate change planning. Using survey data from the Southern Fleurieu Peninsula, South Australia, we present a method for identifying perceived landscape values and climate change risks to describe and quantify their spatial associations. Two spatial data models-vector and raster-and two analytical methods-Jaccard coefficients and spatial cross-correlations were used to describe the spatial associations. Results indicate that perceptions of climate change risk are driven, in part, by the values people assign or hold for places on the landscape. Biodiversity and intrinsic landscape values have strong spatial association with biodiversity loss risk while recreation values have strong spatial association with riparian flooding, sea-level rise and wave action risks. Other landscape values show weak to no spatial association with perceived climate change risks. The methodology described in this research provides a mechanism for government agencies to develop place-based adaptation strategies based on these associations. [ABSTRACT FROM AUTHOR]

1. Perennial plants have been shown to facilitate understorey annual plant species in arid lands through the modification of spatial patterns of resources and conditions. This effect can result from a balance between simultaneously positive and negative interactions, both direct and indirect. This balance may shift with temporal variability in water availability. 2. We conducted a field experiment in a chenopod shrubland in South Australia to separate the effects of shade, below-ground competition, and soil modification by shrubs on the performance of annual plants, and to determine if the strength and direction of the interaction shifted with changes in water availability. 3. Annual plant diversity and seedling density was highest in plots established in open sites away from the dominant shrubs ( Maireana sedifolia). Experimental removal of M. sedifolia increased seedling density compared to plots under undisturbed shrubs and plots where the removed shrub was replaced with artificial shade. Shading of open plots also reduced seedling density. Annual plant biomass was highest in areas where shrubs had been removed and was reduced by artificial shading. Biomass was higher in open plots than under intact shrubs. Experimental water addition did not alter plant density, but increased biomass across all treatments, particularly in artificially shaded bush plots. 4. Synthesis. Our results show that the overall effect of shrubs on the annual plant community in the system is negative under the range of water availabilities experienced during the experiment. This negative net-effect results from a combination of simultaneous facilitation via soil modification, and above- and below-ground competition. Assessment in different systems of different combinations of mechanisms that have simultaneously positive and negative effects will allow us to refine hypotheses seeking to explain the relative importance of facilitation across spatial and temporal gradients. [ABSTRACT FROM AUTHOR]

Summary 1. To explore how rangeland grazing affects native plant diversity at local and regional scales, we measured the frequency of occurrence of plant species along six transects spread across a large region of arid calcareous rangelands in north-western South Australia. Four transects were in commercial sheep-grazed paddocks and two were in otherwise similar lands that had never been developed for pastoralism. Each transect comprised four sites of area 0·5 km2 , at distances of 1, 4, 7 and 10 km from the nearest stock watering point in a paddock, or from a nominal starting point > 10 km from water in the undeveloped lands. 2. Nearly 200 plant species were recorded, but distributions were patchy, with > 30% of species present at < 10% of sites. 3. The apparent influence of pastoral development and proximity to water varied with the scale of inquiry. At the regional level, pastoral development had a predominantly negative effect on the abundance of species: 16 species were less abundant in paddocks than in lands that had never been developed, and only one species was more abundant. Localized trends within paddocks were more positive: significantly more species showed trends of increasing abundance with increasing proximity to watering points and associated grazing activity. 4. The study results are consistent with a general pattern whereby pastoral development enhances richness of plant species at a local scale (by providing opportunities for more species to establish) but has the potential to decrease it at a regional scale (by removing the most grazing-sensitive species from the regional species pool). 5. The results suggest there may be two fundamentally different mechanisms whereby species decline in abundance under grazing. Palatable, drought-hardy, perennial species are more likely to decline in abundance with proximity to water and associated accumulated grazing pressure in paddocks. Uncommon or short-lived species that are selectively... [ABSTRACT FROM AUTHOR]