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Translocation is commonly used in the conservation of threatened species to help mitigate the risk of local extinctions. However, translocations are often limited by knowledge of the species ecological requirements that promote persistence in the landscape. Small translocation trials with a strong experimental design can help to address species knowledge gaps and identify effective strategies for the successful establishment of a threatened species prior to implementing full‐scale planting regimes. In this study, we experimentally translocated 128 plants of the endangered Persoonia hirsuta (Proteaceae) at a dry sclerophyll mining offset in New South Wales (NSW), Australia, and investigated the effects of propagation type (seeds and vegetative cuttings), plant guards, and mulching on short‐term plant growth and survival. Transplants were impacted by herbivory and unprecedented extreme temperatures over summer 2019–2020 with 25 of the 128 plants surviving after 20 months of monitoring. Among the surviving individuals, all but one were seed propagated and 72% of survivors were protected by a plant guard. Short‐term survival and establishment of P. hirsuta translocants was increased by producing plants from seeds, and the use of plant guards with localized mulch. We also identified significantly greater root volume, projected area, and diameter for seedlings than cuttings grown plants. Our study successfully identified several key factors that should be considered for the ongoing management of P. hirsuta and vindicates the importance of small experimental trials when planning threatened plant translocations. [ABSTRACT FROM AUTHOR]

Premise of research. Worldwide, fire-sensitive shrubs have an important but underresearched life history, and in Australia they are threatened by anthropogenic changes to fire regimes and habitat loss. Typically, adults are killed by fire, but they can also senesce and die if interfire intervals are prolonged. Populations can regenerate from seed banks displaying fire-stimulated germination; however, populations are ephemeral, and true population sizes and connectedness are difficult to estimate. Persoonia hirsuta ssp. evoluta is an endangered, inconspicuous, fire-sensitive shrub with a soil-stored seed bank currently known only from a small number of locations within the fire-prone Sydney Basin. Although it appears highly fragmented and populations are typically small, we predicted that its seed bank would buffer populations against loss of genetic diversity and population differentiation. Methodology. We used microsatellite markers to assess genetic variation within three aboveground populations of P. hirsuta separated by up to 25 km. The largest and most isolated population, at Appin, New South Wales, Australia, occurs on a mine site and may be subject to disturbance. We compared levels of genetic diversity and estimated the mating systems and genetic connectedness of plants within the three sites. Pivotal results. As predicted, all populations displayed similar genetic diversity, as judged by expected heterozygosity and allelic richness, and displayed little differentiation. All populations appear predominantly outcrossed. However, STRUCTURE and principal coordinates analyses showed that Appin individuals were distinct from those at the other locations. Conclusions. Our data imply that even for fire-sensitive species with few aboveground populations, genetic diversity can be maintained by the buffering effect of persistent seed banks with diversity reflecting historically greater interpopulation gene flow. While all P. hirsuta sites support comparable genetic diversity, the preservation of known populations is critical. Conservation efforts should include searches for additional populations, fire-stimulated germination of seed banks, and collection of seed for propagation in a nursery or direct sowing. [ABSTRACT FROM AUTHOR]

The frequency and severity of recent natural disasters has raised questions in relation to disaster-related preparedness of the small business sector. Small businesses are an important contributor to local communities and economies. When it comes to recovering from a natural disaster, it is important to support local small businesses to reopen for business as soon as possible. If they are unable to rebound to provide products and services on which we rely as a community, recovery efforts will be curtailed and delayed. This paper provides a practitioner view on the lessons that can be learnt specifically from the Australian experience. The lessons outlined here resonate with small businesses in any disaster recovery context. The insight provided will inform the development of recovery policies and activities in the immediate, short- and long-term at an individual as well as a business level. [ABSTRACT FROM AUTHOR]

The re-use of biosolids is becoming increasingly popular for land applications. However, biosolids may contain elevated levels of metals and metalloids (including mercury) relative to background environmental concentrations. Consequently, reliable mercury analysis is important to allow classification of biosolids and to determine appropriate options for beneficial uses. This paper reports on a comparative study of 12 hotplate wet digestion methods for their suitability for the determination of mercury in biosolids. The methods were applied to mercury biosolids samples from four localities of two different sewage treatment plants in the State of Victoria, Australia. Samples were also spiked with methylmercury chloride and mercury sulphide to evaluate the Hg recovery in each hotplate digestion method. Aqua regia (HCl:HNO3 =3:1), reverse aqua regia (HCl:HNO3 =1:3), nitric, hydrochloric, sulphuric acid and their combinations with or without hydrogen peroxide were studied as wet digestion solutions. The method providing the best mercury recoveries was optimized. Under optimal conditions the corresponding analytical procedure consisted of 1h pre-digestion of 0.4g biosolids sample with 10ml reverse aqua regia with temperature increasing to 110°C and 3h digestion at this temperature. In the last 10min of the digestion step, 2ml hydrogen peroxide were added to ensure complete decomposition of all mercury containing compounds. After filtering and dilution with deionised water (1:10), the concentration of mercury was determined by cold vapour atomic absorption spectrometry. It is expected, that the wet acid digestion method developed in this study will be also applicable to biosolids from other sewage treatment plants and to other types of solid mercury samples with elevated levels of organic matter. [Copyright &y& Elsevier]

Melbourne Water’s Eastern Treatment Plant (ETP) produces a secondary-treated sewage effluent which is chlorinated and discharged into Bass Strait at Boags Rocks, Victoria, Australia. Disappearance of the sensitive brown seaweed Hormosira banksii from rock platforms immediately adjacent to the shore-line discharge was identified in the early 1990s. Subsequently, Melbourne Water and CSIRO undertook an environmental impact assessment and review of land and marine effluent disposal options, which included ambient water quality monitoring, biological monitoring, bioaccumulation studies and toxicity testing of existing effluent to assess the nature and magnitude of the environmental effects. This paper presents data from the toxicity monitoring programs since 2001. Chronic toxicity testing using macroalgal germination and cell division (H. banksii), microalgal growth rate (Nitzschia closterium) and scallop larval development (Chlamys asperrima), confirmed that ammonia was the major cause of effluent toxicity. Results from this toxicity monitoring program were used to develop action trigger values for toxicity for each species, which were then used in a refined monitoring program in 2005–2007. An upgrade of the ETP is in progress to improve nitrification/denitrification in order to reduce ammonia concentrations and the toxicity of the effluent. Toxicity testing with a simulated upgraded effluent confirmed that ammonia concentrations and toxicity were reduced. Estimated “safe” dilutions of effluent, calculated using species sensitivity distributions, decreased from 1:140–300 for existing ETP effluent to 1:20 for nitrified effluent, further confirming that treatment improvements should reduce the impact on marine biota in the vicinity of the discharge. [Copyright &y& Elsevier]

Seagrass meadows form valuable ecosystems, but are considered to have low cultural value due to limited research efforts in this field. We provide evidence that seagrass deposits play a hitherto unrealized central role in preserving valuable submerged archaeological and historical heritage across the world, while also providing an historical archive of human cultural development over time. We highlight three case studies showing the significance of seagrass in protecting underwater cultural heritage in Denmark, the Mediterranean and Australia. Moreover, we present an overview of additional evidence compiled from the literature. We emphasize that this important role of seagrasses is linked to their capacity to form thick sedimentary deposits, accumulating over time, thereby covering and sealing submerged archaeological heritage. Seagrass conservation and restoration are key to protecting this buried heritage while also supporting the role of seagrass deposits as carbon sinks as well as the many other important ecosystem functions of seagrasses.