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Glowworms are the bioluminescent larvae of a group of dipteran insects related to fungus gnats. They require sheltered, consistently moist conditions and are found in aggregations on the walls and ceilings of caves and near streams in wet forests where they attract flying insects as prey. The Waitomo Glowworm Cave in New Zealand receives many thousands of visitors each year to see the colony of the glowworm, Arachnocampa luminosa. The cave climate is managed to ensure the glowworms are not harmed by influxes of dry air, as happened in the 1970s. To monitor the population and warn of catastrophic population declines, time‐lapse photographic monitoring of the glowworm population began in 2011 using a permanent, fixed camera. Photographs are taken 30 min apart. The population exhibits synchronised diurnal cycles of bioluminescence intensity. The time of the acrophase (the peak) of the diurnal cycle varied seasonally between 5 pm in early southern spring and 8 pm in summer. Cross‐correlation analyses with cave and water temperatures incorporating time lags suggest that this annual cycle could be related to changes in the composition or density of prey insects. Annual cycles also occur in the number of glowing larvae and their overall intensity. In most years, the numbers are lowest in winter and increase in spring to produce the brightest display through summer. The summer peak is not seen every year and autocorrelation of the 13‐year time series of count shows signs of a 3‐ to 4‐year cycle beyond the annual periodicity. The availability of prey in the cave chamber could influence the annual cycles in glowworm density, underscoring the need for a deeper knowledge of the bionomics of prey species, mainly Chironomidae (non‐biting midges). The photographic monitoring has proven to be a useful component of the management of the glowworm population. [ABSTRACT FROM AUTHOR]

Context: The concept of the fire regime is central to understanding and managing fire-prone ecosystems globally, and information on past regimes can provide useful insights into species disturbance adaptations. Although observations from satellite imagery or palaeoecological proxy data can provide direct evidence of past, pre-colonial fire regimes, they may be limited in temporal or spatial resolution and are not available for all ecosystems. However, fire-related plant-trait and demographic data offer an alternative approach to understand species–fire regime associations at the ecosystem scale. Aims: We aimed to quantify the life-history strategies and associated fire regimes for six co-occurring shrub and tree species from fire-prone, Mediterranean-climate Banksia Woodlands in south-western Australia. Methods: We collected static demographic data on size structure, seedling recruitment, and plant mortality across sites of varying time since last fire. We combined demographic data with key fire-related species traits to define plant life-history strategies. We then compared observed life histories with a priori expectations for surface, stand-replacing, and mixed-severity fire-regime types to infer historical fire-regime associations. Key results: Fire-killed shrubs and weakly serotinous trees had abundant post-fire seedling recruitment, but also developed multi-cohort populations during fire-free periods via inter-fire seedling recruitment. Resprouting shrubs had little seedling recruitment at any time, even following fire, and showed no signs of decline in the long absence of fire, likely owing to their very long lifespans. Conclusions: The variation in life-history strategies for these six co-occurring species is consistent with known ecological strategies to cope with high variation in fire intervals in a mixed-severity fire regime. Whereas resprouting and strong post-fire seedling recruitment indicate a tolerance of shorter fire intervals, inter-fire recruitment and weak serotiny are interpreted as a bet-hedging strategy to cope with occasional long fire-free periods that may otherwise exceed adult and seed-bank lifespans. Implications: Our findings suggested that Banksia Woodlands have evolved with highly variable fire intervals in a mixed-severity fire regime. Further investigations of species adaptations to varying fire size and patchiness can help extend our understanding of fire-regime tolerances. Information on past fire regimes can provide useful insights into species disturbance adaptations. To test the idea that contemporary demographic parameters provide a signature of past fire regimes, we assessed fire-related plant life-history strategies by using static demographic data collected along a 1–35-year fire-age chronosequence for species with a variety of traits. Species displayed a collection of life-history strategies associated with a historical mixed-severity fire regime, including adaptations for short and long fire intervals, interacting with varying fire severity. Photograph by Russell Miller. [ABSTRACT FROM AUTHOR]

Questions: Annual species have evolved sets of germination cues that are thought to be predictive of the post‐germination environment. In naturally patchy environments, germination microsites often vary considerably in the amount of light they receive and in the diurnal temperature fluctuations they experience. However, whether species' differential germination responses to light and temperature are associated with their spatial patterns of occurrence remains largely untested. Location: Mediterranean‐climate woodlands in Southwest Western Australia. Methods: We surveyed species' occurrences in annual plant communities in 150 quadrats across gradients of canopy cover and litter cover. Nineteen species recorded in this survey were then included in a germination experiment that manipulated (1) Light vs Dark (12 h light or continuous dark) approximating seeds near the soil surface vs those covered by litter and (2) Cold vs Warm temperature regimes (7/18°C and 7/24°C) approximating diurnal fluctuations experienced in shaded vs sun‐exposed microsites, respectively. Results: In the germination experiment, six species had highest germination probabilities in the Light treatment (regardless of temperature), five in Cold + Light, one in Warm + Light, two were indifferent to the treatments, and four did not germinate at all. Binomial linear mixed‐effects models showed that species' maximum responses to light and temperature did not explain their spatial distributions along canopy cover and litter cover gradients, contrary to theoretical expectations of germination being a strong driver of species' occurrences. Conclusions: Despite variation in species' responses to experimental treatments, no association was found with their field microsite associations. Germination strategies in our system were wider than expected for Mediterranean systems. Our results support that germination cues are not strong drivers of microhabitat associations in this system. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Conservation seed banks maintain collections of many seed‐bearing plant species, providing germplasm and data to support management of wild populations. However, a proportion of plant species produce seeds that are difficult to collect, dry, store and utilise; these are known as 'exceptional' species. Here we tested a framework for identifying exceptional species, to document examples and provide case studies within the Australian flora. We present a workflow that may be used to identify additional exceptional species, and direct efforts to establish appropriate collection types (seeds and/or living collections, tissue culture or cryopreservation) for their ex situ conservation. Summary: Seed banking is well established to contribute to the conservation of many seed‐bearing plant species ex situ for future use in restoration, translocation, agriculture and horticulture. In Australia, over 67% of currently listed threatened plants are represented in conservation seed banks. However, there are challenges to conserving the full extent of plant diversity in seed banks, with growing recognition that we need to think beyond conventional seed banking methods to conserve 'exceptional' plant species that are difficult to collect, store and germinate. We examine how the framework for identification of such species can be applied to the Australian flora, using examples from the recently published guidelines for 'Plant Germplasm Conservation in Australia' and case studies and data arising from the Australian Academy of Science Fenner Conference on the Environment 'Exceptional Times, Exceptional Plants'. We present a workflow to assist conservation decision‐makers and practitioners in identifying exceptional species and overcoming barriers to storage of germplasm, enabling appropriate ex situ collection types to be established via seeds, living collections, tissue culture, cryopreservation or a combination of these. Australia's seed conservation sector continues to expand, with increasing expertise, facilities and networks established to conserve a diversity of plant species; however, resolving the challenges relating to each exceptionality factor requires significantly more time, labour and collaboration than current capacity allows. Understanding the barriers to conservation and production of healthy plants, via germination or other methods of propagation, is a critical component of conserving species long‐term and ultimately returning plants to the landscape. [ABSTRACT FROM AUTHOR]

Post‐mining scenarios present challenges for restoration in a wide range of environments, especially in the context of climate change. The source of seed for restoration has been an issue of intense focus, as seed provenance can impact plant fitness and restoration outcomes. However, post‐mining landscapes require substrate reconstruction prior to vegetation re‐establishment. Critically, the relative importance of provenance and substrate in ecosystem recovery has been rarely quantified in a statistically rigorous framework. We established a large provenance trial with Banksia attenuata and Eucalyptus todtiana at two Western Australian mine sites in post‐mining reconstructed and adjoining un‐mined substrates. We show that site and substrate were 4 and 26 times more important than provenance in explaining survival for B. attenuata and E. todtiana, respectively. At one site, there was 100% mortality in the post‐mining substrate but high survival and no clear provenance effect in the un‐mined substrate. At the second site, there was again no clear provenance effect, but E. todtiana survival was higher in the post‐mining than un‐mined substrate. Our results show that post‐mining substrate changes can overwhelm provenance issues. Consequently, where substrates are highly impacted, alternative restoration targets and/or greater investment in substrate research are needed to improve restoration outcomes. Due to the thousands of mines across the world, this is an internationally relevant finding with important implications for investment into global ecosystem recovery. [ABSTRACT FROM AUTHOR]

Context. Seeding is common practice for ecological restoration, but establishment rates can be low. For seeds to successfully establish they must transition through early life stages of germination, emergence, and (initial) survival. Examining these demographic processes for seeds sown under a range of abiotic conditions can identify failure points and inform techniques to improve seed use. Aims. Here we quantified seed and seedling life-stage transitions in five reconstructed soils across four varying levels of simulated rainfall using five species (Acacia hilliana, Acacia inaequilatera, Indigofera monophylla, Triodia pungens, and Triodia wiseana) commonly seeded for mined land restoration of the Pilbara bioregion in north-west Western Australia. Methods. Germination, emergence, and survival were measured over a 6 week period and transition probabilities between each life-stage transition were modelled for each treatment combination. Key results. For four species, both rainfall amount and/or soil substrate significantly influenced germination probability. Rainfall was the more significant determinant, with germination greatest under the higher rainfall regimes of 120-280 mm, irrespective of soil type. Following germination, emergence of both Acacia spp. was positively influenced by soils containing topsoil, suggesting the microenvironment of soils containing topsoil was most favourable during this emergence phase. The effect of substrate was less clearcut for I. monophylla and Triodia spp, where emergence was most limited in substrates comprised solely of overburden waste material and the lowest rainfall regime exacerbated emergence failure, relative to germination success. When compared to the well-watered, 100% topsoil substrate, seedling survival of all species was most constrained in the 100% overburden waste, demonstrating these reconstructed mining substrates compromise seedling recruitment. Conclusions. This study underscores that successful seedling recruitment in this ecosystem is dependent on frequent, and repeated, rainfall events above a certain threshold (≥120 mm) and highlights the beneficial effects of sowing seeds in a substrate containing topsoil. Implications. Future seeding technologies should focus on improving the moisture relations of the microsite to offset the recruitment challenges experienced by seeds sown in hostile growing environments such as the overburden wastes tested here. [ABSTRACT FROM AUTHOR]

Since 1974, the number of entomology-specific courses or subjects available at Australian universities, including the University of Queensland, has plummeted. Today, discussion of the status of tertiary-level entomological education tends to be a lament, as older entomologists view with appreciation the depth and diversity of their own educational experiences. I will attempt to contextualise the university-level changes and examine ways of ensuring entomological education continues to move forward. Undergraduate education is unlikely to go back to the comprehensive practical skills basis that was prevalent in the late 1900s: such skills will be obtained in higher degree research or in employment. We need to acknowledge that education is becoming more about helping students manage and contextualise information than it is about lecturing to them. [ABSTRACT FROM AUTHOR]

Larvae of the genus Megalopyge (Lepidoptera: Zygaenoidea: Megalopygidae), known as asp or puss caterpillars, produce defensive venoms that cause severe pain. Here, we present the anatomy, chemistry, and mode of action of the venom systems of caterpillars of two megalopygid species, the Southern flannel moth Megalopyge opercularis and the black-waved flannel moth Megalopyge crispata. We show that megalopygid venom is produced in secretory cells that lie beneath the cuticle and are connected to the venom spines by canals. Megalopygid venoms consist of large aerolysin-like pore-forming toxins, which we have named megalysins, and a small number of peptides. The venom system differs markedly from those of previously studied venomous zygaenoids of the family Limacodidae, suggestive of an independent origin. Megalopygid venom potently activates mammalian sensory neurons via membrane permeabilization and induces sustained spontaneous pain behavior and paw swelling in mice. These bioactivities are ablated by treatment with heat, organic solvents, or proteases, indicating that they are mediated by larger proteins such as the megalysins. We show that the megalysins were recruited as venom toxins in the Megalopygidae following horizontal transfer of genes from bacteria to the ancestors of ditrysian Lepidoptera. Megalopygids have recruited aerolysin-like proteins as venom toxins convergently with centipedes, cnidarians, and fish. This study highlights the role of horizontal gene transfer in venom evolution. [ABSTRACT FROM AUTHOR]

Context: In ecosystems where rainfall is episodic or highly seasonal, plant recruitment from a soil-stored seed bank occurs during periods of elevated soil moisture conducive to germination and seedling establishment. The release of seed dormancy in response to environmental conditions has significant consequences for the temperature window over which germination occurs, and as such the timing of germination can vary between years. Aims: We aimed to understand in seeds of two species of Rutaceae, Diplolaena dampieri and Rhadinothamnus anceps , how dormancy loss and germination timing is influenced by warm stratification. Methods: We tested the germination response to temperatures between 5 and 30°C following increasing durations (1–12 and 4–12 weeks) of warm stratification at 20, 25, or 30°C. Key results: Warm stratification for 1–8 weeks at 30°C progressively alleviated seed dormancy in D. dampieri and R. anceps , increasing germination proportion from ~0.1 to ~0.5 in both species. Stratification duration was optimal at 30°C for between 4 and 8 weeks depending on species. Warm stratification was not affected by water stress down to −0.8 Mpa. Application of aerosol smoke did not significantly improve germination, and heat treatments had a negative effect on final germination proportion. Conclusions: As dormancy was progressively alleviated, the range of temperatures that support germination increased for D. dampieri and decreased for R. anceps , allowing for confirmation of type 1 and type 2 non-deep physiological dormancy (PD), respectively. Implications: Arising from this conclusion, we suggest that in Mediterranean climates, type 1 and 2 PD dictate risk-taking and risk-avoiding ecological strategies by shifting the thermal requirements for germination towards that characteristic of the early- or mid-germination season. Classification of non-deep PD may offer a structured approach to predict how temperature requirements shift during dormancy loss, which will provide insight into seed germination response to year-to-year variation in seasonal environmental conditions. Seeds of two Australian species of Rutaceae were sown under laboratory conditions to investigate the effect of duration of exposure to warm moist temperatures (20, 25 and 30°C) on germination when moved to cooler temperatures (5–30°C). Both species had a greater germination proportion following 4–8 weeks exposure to 30°C but displayed variable responses under different germination temperatures. [ABSTRACT FROM AUTHOR]

Understanding the relative longevity of different seed lots, perhaps of different species or genotypes, but also following production under different environments or using different cultivation methods, or following different post-harvest treatments, is relevant to anyone concerned with the retention of seed lot viability and vigour during storage. However, different scientists over the years have used different conditions to assess seed lot longevity, as well as different variables as the measure of 'longevity.' Here, we give some of the backgrounds to how two standard protocols, with an open and closed system respectively, were derived, and explain why we consider p 50, defined as the time during storage when seed lot viability, as measured through a germination test, has declined to 50%, is a suitable longevity trait parameter. [ABSTRACT FROM AUTHOR]

Environmentally cued germination may play an important role in promoting coexistence in Mediterranean annual plant systems if it causes niche differentiation across heterogeneous microsite conditions. In this study, we tested how microsite conditions experienced by seeds in the field and light conditions in the laboratory influenced germination in 12 common annual plant species occurring in the understorey of the York gum-jam woodlands in southwest Western Australia. Specifically, we hypothesized that if germination promotes spatial niche differentiation, then we should observe species-specific germination responses to light. In addition, we hypothesized that species' laboratory germination response may depend on the microsite conditions experienced by seeds while buried. We tested the laboratory germination response of seeds under diurnally fluctuating light and complete darkness, which were collected from microsites spanning local-scale environmental gradients known to influence community structure in this system. We found that seeds of 6 out of the 12 focal species exhibited significant positive germination responses to light, but that the magnitude of these responses varied greatly with the relative light requirement for germination ranging from 0.51 to 0.86 for these species. In addition, germination increased significantly across a gradient of canopy cover for two species, but we found little evidence to suggest that species' relative light requirement for germination varied depending on seed bank microsite conditions. Our results suggest that variability in light availability may promote coexistence in this system and that the microsite conditions seeds experience in the intra-growing season period can further nuance species germination behaviour. [ABSTRACT FROM AUTHOR]

Changes in fire regimes due to climate change and fire management practices are affecting the timing, length, and distribution of vegetation fires throughout the year. Plant species responses and tolerances to fire differ from season to season and are influenced by species-specific phenological processes. The ability of seeds to tolerate extreme temperatures associated with fire is one of these processes, with survival linked to seed moisture content at the time of exposure. As fire is more often occurring outside historic dry fire seasons, the probability of fire occurring when seeds are hydrated may also be increasing. In this study, we set out to understand the seasonal dynamics of seed hydration for seeds of Banksia woodland species, and how certain seed traits interact with environmental conditions to influence survival of high temperatures associated with fire. We measured the moisture content of seeds buried to 2 cm in the soil seed bank for four common native species and one invasive species on a weekly basis throughout 2017, along with soil moisture content and environmental correlates. We determined water sorption isotherms at 20°C for seeds of each species and used these functions to model weekly variation in seed water activity and predict when seeds are most sensitive to soil heating. Using Generalised additive models (GAMs), we were able to describe approximately 67% of the weekly variance in seed water activity and explored differences in seed hydration dynamics between species. Seed water activity was sufficiently high (i.e., ≥ 0.85 a w) so as to have created an increased risk of mortality if a fire had occurred during an almost continuous period between May and November in the study period (i.e., 2017). There were brief windows when seeds may have been in a dry state during early winter and late spring, and also when they may have been in a wet state during summer and late autumn. These data, and the associated analyses, provide an opportunity to develop approaches to minimize seed mortality during fire and maximize the seed bank response. [ABSTRACT FROM AUTHOR]

Unseasonal fire occurrence is increasing globally, driven by climate change and other human activity. Changed timing of fire can inhibit postfire seedling recruitment through interactions with plant phenology (the timing of key processes, e.g., flower initiation, seed production, dispersal, germination), and therefore threaten the persistence of many plant species. Although empirical evidence from winter‐rainfall ecosystems shows that optimal seedling recruitment is expected following summer and autumn (dry season) fires, we sought experimental evidence isolating the mechanisms of poor recruitment following unseasonal (wet season) fire. We implemented a seed‐sowing experiment using nine species native to fire‐prone, Mediterranean‐climate woodlands in southwestern Australia to emulate the timing of postfire recruitment and test key mechanisms of fire seasonality effects. For seeds sown during months when fire is unseasonal (i.e., August–September: end of the wet winter season), seedling recruitment was reduced by up to 99% relative to seeds sown during seasonal fire months (i.e., May–June: end of the dry summer season) because of varying seed persistence, seedling emergence, and seedling survival. We found that up to 70 times more seedlings emerged when seeds were sown during seasonal fire months compared to when seeds were sown during unseasonal fire months. The few seedlings that emerged from unseasonal sowings all died with the onset of the dry season. Of the seeds that failed to germinate from unseasonal sowings, only 2% survived exposure on the soil surface over the ensuing hot and dry summer. Our experimental results demonstrate the potential for unseasonal fire to inhibit seedling recruitment via impacts on pregermination seed persistence and seedling establishment. As ongoing climate change lengthens fire seasons (i.e., unseasonal wildfires become more common) and managed fires are implemented further outside historically typical fire seasons, postfire seedling recruitment may become more vulnerable to failure, causing shifts in plant community composition towards those with fewer species solely dependent on seeds for regeneration. [ABSTRACT FROM AUTHOR]

Venoms have evolved independently several times in Lepidoptera. Limacodidae is a family with worldwide distribution, many of which are venomous in the larval stage, but the composition and mode of action of their venom is unknown. Here, we use imaging technologies, transcriptomics, proteomics, and functional assays to provide a holistic picture of the venom system of a limacodid caterpillar, Doratifera vulnerans. Contrary to dogma that defensive venoms are simple in composition, D. vulnerans produces a complex venom containing 151 proteinaceous toxins spanning 59 families, most of which are peptides <10 kDa. Three of the most abundant families of venom peptides (vulnericins) are 1) analogs of the adipokinetic hormone/corazonin-related neuropeptide, some of which are picomolar agonists of the endogenous insect receptor; 2) linear cationic peptides derived from cecropin, an insect innate immune peptide that kills bacteria and parasites by disrupting cell membranes; and 3) disulfide-rich knottins similar to those that dominate spider venoms. Using venom fractionation and a suite of synthetic venom peptides, we demonstrate that the cecropin-like peptides are responsible for the dominant pain effect observed in mammalian in vitro and in vivo nociception assays and therefore are likely to cause pain after natural envenomations by D. vulnerans. Our data reveal convergent molecular evolution between limacodids, hymenopterans, and arachnids and demonstrate that lepidopteran venoms are an untapped source of novel bioactive peptides. [ABSTRACT FROM AUTHOR]

Variations in the degree of seed dormancy expressed among conspecific populations provide a basis for improving understanding of the mechanisms controlling species persistence, especially in fire-prone ecosystems. We investigated seed germination of 12 Anigozanthos flavidus populations in response to various fire-related cues that included exposure to karrikinolide, glyceronitrile and smoke water at five temperatures, and the effects of heat shock and its interaction with glyceronitrile. Seeds from populations with deep-degree dormancy (DD) and light-degree dormancy (LD) were subjected to 0–8 months of after-ripening, and the viability of the ungerminated seeds was tested. The degree of seed dormancy and responses to fire-related cues were highly variable among populations. Glyceronitrile and smoke water significantly improved germination in 12 and 8 populations respectively. Heat significantly enhanced germination in all populations, but was less effective when combined with glyceronitrile. After-ripening for 3 months increased germination, whereas ≥4 months led to secondary dormancy or loss of viability. Loss of viability was greater for DD than for LD seeds. Interpopulation variations in the degree of seed dormancy, seed germination requirements for fire-related cues and germination viability in response to after-ripening in A. flavidus contribute to persistence in the variable and unpredictable Mediterranean environment. We investigated seed germination of 12 Anigozanthos flavidus populations in response to fire-related cues and after-ripening durations. We found that dormancy degrees were highly variable among populations. Glyceronitrile and heat significantly improved germination in 12 populations, but was less effective when combined. After-ripening for 4 months or more led to loss of viability, especially for deep-degree dormant populations. [ABSTRACT FROM AUTHOR]

Many plant species in fire‐prone environments maintain persistence through fire via soil seedbanks. However, seeds stored within the soil are at risk of mortality from elevated soil temperatures during fire. Seeds may be protected from fire‐temperature impacts by burial, however, those buried too deeply may germinate but fail to emerge. Thus, successful post‐fire seed regeneration is contingent upon a trade‐off between burial depth and survival through fire.We examined the relationships between seedling emergence behaviour, seed survival and soil temperatures during fire in 13 native and four non‐native woodland species in southwestern Australia. We assessed total seedling emergence per depth, maximum seedling emergence depth and seedling emergence speed from seeds planted at eight depths (0, 1, 2, 3, 4, 5, 7, 10 cm). Soil temperatures were quantified using distributed temperature sensing in optic fibre (DTS), measured continuously between 1 and 10 cm in depth (temperatures were subsequently categorized into 1 cm increments for analysis) during five experimental fires in beds with fine fuels manipulated between 8 and 20 t/ha. Using seed survival and emergence success relative to soil temperatures, we determined vulnerability of seedling emergence relative to soil temperatures generated by combustion of fuel quantities typically observed in woodlands.Maximum depth of emergence varied between species from 2 to >10 cm, with a positive linear correlation to seed mass. Maximum soil temperatures from the two highest fuel masses exceeded seed lethal thresholds (T50—representing temperatures lethal to 50% of seeds) of at least five species. Lethal temperatures were exceeded at all potential emergence depths for all three grass species, and all four non‐native species studied. Of the remaining 10 species, temperatures did not exceed the lethal thresholds under any of the fuel mass levels tested. We found no relationship between lethal temperature thresholds and maximum emergence depth.Our data demonstrate that seeds exhibit variation in their response to soil heating and capacity to emerge from depth, with three distinct functional responses amongst our study species, which enable persistence through, and recruitment following, fire. Such variation in species attributes and fuel mass may lead to heterogeneity (within fires) or divergent trajectories (among fires) in community response under changed fire regime. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Cyanobacteria are photosynthetic bacteria that form a fundamental part of soil biocrusts, enhance soil function and structure, and can promote plant growth. We assessed the potential of cyanobacteria as a seed bio‐primer for mine‐site restoration in an arid region in Western Australia, examining its effects on native plant growth and the characteristics of mine soil substrates used in dryland restoration. Cyanobacteria strains indigenous to the study region (Leptolyngbya sp., Microcoleus sp., Nostoc sp., and Scytonema sp.) were used to create an inoculant. Seeds of seven native plant species were bio‐primed with the inoculant, and their germination and growth assessed in a laboratory experiment. Seedling growth after bio‐priming was assessed in a glasshouse experiment for a subset of three species, in two different substrates (topsoil and mine waste). Soil properties related to soil function, e.g. total organic carbon, total nitrogen, and microbial activity, were also measured. Minor effects on germination were recorded with only significantly higher germination rates reported in E. gamophylla. Soil parameters were generally higher in topsoil than in mine waste, regardless of bio‐priming treatment. However, bio‐priming resulted in seedlings of four species producing longer radicles and/or shoots. For example, seedling root lengths of bio‐primed G. wickhamii were 57% larger than the control treatment (30.1 ± 4.3 and 13.0 ± 1.6 mm, respectively); and shoots of T. wiseana were 54% longer in the bio‐primed treatment (18.6 ± 1.6 mm) compared to the control (8.53 ± 1.4 mm). Overall, our results highlight that bio‐priming with cyanobacteria may improve plant growth for some species commonly used in dryland restoration. [ABSTRACT FROM AUTHOR]

Aims: We aimed to understand the influence of differing soil rock content on seedling emergence of a dominant arid zone grass critical to mine restoration (Triodia pungens R.Br.). We assessed whether emergence mortality resulting from seedlings failing to navigate rocky soils contributes meaningfully to failed recruitment and the maximum emergence depth. Methods: Cleaned seeds and florets (the natural dispersal unit) were buried at discrete depths of 0, 5, 10, 15, 20, 30, and 40 mm in three soil-rock matrices of varying rock content (soil sieved to <5 mm, sieved to <25 mm, or left un-sieved). Results: Rock content reduced emergence of seeds buried below 15 mm and truncated the maximum emergence depth. When seeds were buried at 5 mm; near the modelled 6.0 mm optimal depth, any failure to emerge was largely attributable to failed seed germination. However, when seeds were buried greater than 20 mm, failure of pre-emergent seedlings to reach the surface became the significant factor contributing to failed emergence. Florets failed to recruit under all scenarios. Conclusions: Soil rock content can influence critical seed germination and emergence life stages and therefore the optimal seed recruitment depth. Emergence of deeply (>20 mm) buried seeds is likely restricted by rocks imposing a physical barrier to recruitment. [ABSTRACT FROM AUTHOR]

Dung beetles (Scarabaeinae) are mainly coprophagous. Globally, many species co‐exist with large mammalian fauna in grasslands and savannahs. However, tropical and subtropical rainforests, where large herbivorous mammals are scarce, support numerous dung beetle species. Many rainforest dung beetles have been shown to be generalist saprophages or specialists on non‐dung food resources. In Australian rainforests, observations of native dung beetles have indicated that some species are attracted to other resources such as fruit or fungi, although the extent to which this occurs is not known. To learn more about the diet breadth of Australian native rainforest dung beetles, we assessed their attraction to a range of baits, including two types of dung, four types of carrion from both vertebrates and invertebrates, three types of rotting fruit and rotting mushrooms. We primarily surveyed rainforest sites but included two dry open‐forest sites for comparisons. Of the two groups of Australian native dung beetles (Onthophagini and Australian endemic genera), the latter dominated the rainforest dung beetle fauna and were attracted to a greater variety of baits compared with Onthophagini. The Onthophagini were dominant in open forest and were more likely to be attracted to a particular bait type, primarily dung. Our findings suggest that many of the species belonging to the 'Australian endemic genera' are generalist feeders and their ability to utilise a range of food resources contributes to their abundance and diversity in Australian rainforests. [ABSTRACT FROM AUTHOR]

The methods used to distribute seeds influence the success of a restoration project. We surveyed 183 restoration practitioners from across the globe with the aim of identifying common limitations to the effective use of mechanical direct seeding in large‐scale restoration practice to highlight avenues for design improvement to mechanized seeding equipment. Results from this survey show that direct seeding methods are commonly used for ecological restoration and agree with other studies that suggest the method can achieve results much quicker and cheaper than the alternative of distributing nursery‐grown tube stock. However, this study indicates that current mechanical direct seeding methods lack adequate control of seed sowing depth and spatial distribution and highlight that the inability to sow seeds of varying morphology over complex topography are common limitations to direct seeding. To improve restoration success, engineering improvements to mechanical direct seeders used in large‐scale restoration should focus in particular on addressing issues of precision of delivery for diverse seed types and landscapes. [ABSTRACT FROM AUTHOR]

Cephalotus follicularis is an ecologically unique, taxonomically isolated and range-restricted carnivorous plant that occurs exclusively within vulnerable wetland habitats in coastal south-western Australia. Very little is known about the reproductive biology of this iconic plant species, particularly in relation to seed dormancy and the specific requirements for germination. This knowledge gap must be filled to facilitate the establishment of conservation and management initiatives for the species, as Cephalotus is increasingly impacted by habitat loss, alteration to natural hydrological and fire regimes and, in recent times, climatic change. This study aimed to determine the type of seed dormancy that the seeds of Cephalotus possess, determine the optimum conditions required for seed germination, and examine the storage behaviour of seeds. The seeds of Cephalotus are small (1.0 × 0.5 mm), lightweight (0.1 mg) and remain indehiscent within a wind-dispersed hairy achene. Results suggest that the seeds may exhibit some sensitivity to desiccation and appear to be short lived (<12 months) when stored at 23°C. Maximum germination was achieved after 16 weeks incubation at 15°C for seeds removed from the protective outer layer of the achene, while seeds retained within the protective outer layer displayed lower germination success. The post-ripening morphological changes in the embryo, limited response to gibberellic acid, and the long time period required for germination suggests that the seeds exhibit morphophysiological dormancy, with a fraction of seeds remaining dormant for a period of time post-dispersal. These results highlight the importance of limiting hydrological alteration within the few remaining habitats that continue to support Cephalotus , but to ensure its long-term protection, further research focusing on phenology and in situ recruitment is required. Cephalotus follicularis is an ecologically unique carnivorous plant known only from small area of south-western Australia. Very little is known about its reproductive biology: this has hindered the establishment of conservation and management initiatives. This study determined that the seeds of C. follicularis possess morphophysiological dormancy, and examined the optimum conditions required for seed germination. Results highlight the importance of limiting hydrological alteration within the few remaining habitats that continue to support C. follicularis in order to preserve the species. [ABSTRACT FROM AUTHOR]

The flora of Mediterranean ecosystems contains families with species having fully and under-developed embryos in their seeds. After-ripening for physiological dormancy release and smoke influence germination in many species. We investigated how after-ripening and embryo growth interact with smoke to influence the temporal dynamics of seedling emergence among fire ephemerals. Seeds were placed in the field and under standardized (50% relative humidity, 30°C) laboratory conditions to test the effects of summer conditions on physiological dormancy loss. Germination was tested with water or smoke compounds (smoke water, KAR1) at a simulated autumn/winter temperature (18/7°C). The timing and amount of seedling emergence with smoke was observed for seeds exposed to near-natural conditions. During summer, physiological dormancy was broken in all species, enabling germination at autumn/winter but not summer temperatures; no embryo growth occurred in seeds with under-developed embryos. At the start of the wet season, seedling emergence from seeds with fully developed embryos occurred earlier than from seeds with under-developed embryos. In a non-consistent manner among our study species, smoke and smoke compounds influenced the rate of embryo growth and amount of germination. Effects of smoke were noticeable in terms of number of emergents in the first emergence season. Among ecologically similar species, we have shown (1) that both thermal and embryo traits exclude germination in the summer, (2) how embryo size influences the timing of seedling emergence in autumn–winter, and (3) a reduced requirement for smoke in the second emergence season after a fire with a shift to reliance on seasonal cues for emergence. [ABSTRACT FROM AUTHOR]

Fire has long shaped biological responses of plants and plant communities in many ecosystems; yet, uncontrolled wildfire frequently puts people and infrastructure at risk. Fuel or hazard reduction burning outside of the historic fire season is a common and widespread practice aimed at reducing the risk of high‐severity fires, which ideally also considers biodiversity values. Within fire‐prone systems, seed banks are critical for plant species' regeneration, and seeds are typically adapted to survive the passage of fire and to regenerate in response to cues associated with historic fire regimes. However, species‐specific tolerances to the heat from fire exist; likely influenced by a range of physical, physiological, and morphological seed traits, which may differ between seasons. The identification of these tolerances and associated seed traits may inform fire and species management.We determined the lethal temperatures for seeds in relation to their moisture content, and other key traits that we hypothesised may be associated with survival. Seeds from 14 native species and 4 species non‐native to fire‐prone Mediterranean climate Banksia woodlands of south‐west Western Australia were exposed to temperatures between 50 and 180°C for 3 min at three different moisture contents. The temperature at which half the seeds were killed (T50) was estimated using nonlinear modelling. Seed mass, seed shape, embryo type, plant resprouting ability, seed storage syndrome, and native/non‐native status were quantified and modelled for their relationship with T50.Increased moisture content was a significant predictor of elevated seed mortality. Seeds with higher moisture (95% relative humidity [RH]) content perished at much lower temperatures. Seeds with low moisture content (15% or 50% RH) were able to survive significantly higher temperatures (median increase of 38 and 31°C higher respectively). Seeds with basal embryos showed significantly lower T50 than other embryo types.Synthesis. Seeds with elevated moisture contents have lower lethal temperature thresholds, leading to increased seed mortality during fire events when seeds (and soils) are moist. Thermal tolerance varied among coexisting species within this fire‐prone system. These data suggest potential concern for the impacts of aseasonal burning practices (i.e., cool/wet season burning), and highlight the importance of taking seed moisture content into account when planning and implementing prescribed burning. [ABSTRACT FROM AUTHOR]

Summary: Trait‐based approaches have improved our understanding of plant evolution, community assembly and ecosystem functioning. A major challenge for the upcoming decades is to understand the functions and evolution of early life‐history traits, across levels of organization and ecological strategies. Although a variety of seed traits are critical for dispersal, persistence, germination timing and seedling establishment, only seed mass has been considered systematically. Here we suggest broadening the range of morphological, physiological and biochemical seed traits to add new understanding on plant niches, population dynamics and community assembly. The diversity of seed traits and functions provides an important challenge that will require international collaboration in three areas of research. First, we present a conceptual framework for a seed ecological spectrum that builds upon current understanding of plant niches. We then lay the foundation for a seed‐trait functional network, the establishment of which will underpin and facilitate trait‐based inferences. Finally, we anticipate novel insights and challenges associated with incorporating diverse seed traits into predictive evolutionary ecology, community ecology and applied ecology. If the community invests in standardized seed‐trait collection and the implementation of rigorous databases, major strides can be made at this exciting frontier of functional ecology. [ABSTRACT FROM AUTHOR]

Background and Aims Substantial evidence supports the hypothesis that morphophysiological dormancy (MPD) is the basal kind of seed dormancy in the angiosperms. However, only physiological dormancy (PD) is reported in seeds of the ANA-grade genus Nymphaea. The primary aim of this study was to determine the kind of dormancy in seeds of six species of Nymphaea from the wet–dry tropics of Australia. Methods The effects of temperature, light and germination stimulants on germination were tested on multiple collections of seeds of N. immutabilis, N. lukei, N. macrosperma, N. ondinea, N. pubescens and N. violacea. Embryo growth prior to hypocotyl emergence was monitored. Key Results Germination was generally <10 % after 28 d in control treatments. Germination percentage was highest at 30 or 35 °C for seeds exposed to light and treated with ethylene or in anoxic conditions in sealed vials of water, and it differed significantly between collections of N. lukei, N. macrosperma and N. violacea. Seeds of N. pubescens did not germinate under any of the conditions. Embryo growth (8–37 % in length) occurred before hypocotyl emergence (germination) in seeds of the five species that germinated. Conclusions Fresh seeds were dormant, and the amount of pregermination embryo growth in seeds of N. lukei and N. immutabilis was relatively small, while in seeds of N. macrosperma, N. ondinea and N. violacea it was relatively large. Thus, seeds of N. lukei and N. immutabilis had PD and those of N. macrosperma, N. ondinea and N. violacea had MPD. Overall, we found that seeds in the most phylogenetically derived clades within Nymphaea have MPD, suggesting that PD is the most likely basal trait within the Nymphaeales. This study also highlights the broad range of dormancy types and germination strategies in the ANA-grade angiosperms. [ABSTRACT FROM AUTHOR]

Morphophysiological dormancy (MPD) is predominantly found in seeds of temperate regions and is uncommon in arid biomes. MPD has been reported in a number of Hibbertia (Dilleniaceae) species of temperate Australia, and in a single species of the arid zone, H. glaberrima. This study aimed to examine the dormancy and germination ecology of seeds of H. glaberrima. Seeds were subjected to temperature stratification treatments designed to mimic summer and autumn conditions in the Pilbara region of Western Australia. Seed germination and embryo growth were measured. We also tested the interaction between temperature stratification and cycles of drying and wetting designed to mimic sporadic rainfall events. All temperature and moisture treatments were tested in combination (+/–) with the smoke-derived chemical karrikinolide (KAR1). Exposing dormant seeds to temperatures suitable for warm stratification (35°C) for ≥ 8 weeks, followed by incubation at 25°C, resulted in significantly higher germination compared with non-stratified seeds. Exposing seeds to dry/wet cycling in conjunction with temperature stratification did not significantly increase germination. Exposure to KAR1 increased germination under most conditions. Once seeds are shed during October to December, they are exposed to hot and sporadically wet conditions over summer, allowing MPD to be overcome in a proportion of the seed population. Seeds may germinate in autumn (March to April), in conjunction with cooler temperatures. More deeply dormant individuals may require more than one summer to overcome dormancy. Similar to other species occurring in fire-prone ecosystems, fire also plays a crucial role in the germination ecology of H. glaberrima. [ABSTRACT FROM AUTHOR]

Seed dormancy can present a significant barrier to restoration outcomes in dryland systems. Physical and combinational (physical + physiological) dormancy are prevalent among seeds of many herbaceous perennials used in restoration of drylands throughout the western United States. Although many techniques designed to alleviate these dormancy traits exist, their efficacy is species specific, may result in embryo damage, and may have limited large-scale application. To identify the most effective means of dormancy alleviation with the potential to be used on an operational scale, we examined the effects of 16 temperature-based techniques (altering temperature and duration of wet heat, freezing and wet heat, and freeze-thaw cycles) and 6 abrasion-based techniques (altering pneumatic scarification length or using a single duration of manual scarification) on the enhancement of seed permeability among two physically dormant (western prairie clover [ Dalea ornata {Douglas} Eaton & Wright] and Munro’s globemallow [ Sphaeralcea munroana {Douglas} Spach]) and two combinationally dormant species (basalt milkvetch [ Astragalus filipes Torr. ex A. Gray] and longspur lupine [ Lupinus arbustus {Douglas} ex Lindl.]). We first assessed seed imbibition following exposure to all temperature- and abrasion-based techniques to identify those most successful at promoting seed permeability and then evaluated the effectiveness of those techniques through a series of germination experiments. For combinationally dormant species, we also tested whether exposure to GA 3 enhanced germination. Abrasion-based techniques were more effective than temperature-based techniques at improving water uptake across all species. Pneumatic scarification significantly improved germination, but optimal treatment durations were species specific. GA 3 did not enhance germination under the tested conditions. We conclude that pneumatic scarification is a fast, safe, and effective method for alleviating physical seed dormancy with a potential to be scaled up for operational use in restoration. [ABSTRACT FROM AUTHOR]

We explore a recent, innovative variation of closed-system respirometry for terrestrial organisms, whereby oxygen partial pressure (PO2) is repeatedly measured fluorometrically in a constant-volume chamber over multiple time points. We outline a protocol that aligns this technology with the broader literature on aerial respirometry, including the calculations required to accurately convert O2 depletion to metabolic rate (MR). We identify a series of assumptions and sources of error associated with this technique, including thresholds where O2 depletion becomes limiting, that impart errors to the calculation and interpretation of MR. Using these adjusted calculations, we found that the resting MR of five species of angiosperm seeds ranged from 0.011 to 0.640 ml g-1 h-1, consistent with published seed MR values. This innovative methodology greatly expands the lower size limit of terrestrial organisms that can be measured, and offers the potential for measuring MR changes over time as a result of physiological processes of the organism. [ABSTRACT FROM AUTHOR]

Seed biology in the annual herbaceous flora of ecologically stressful, seasonally wet habitats remains largely unexplored. Temporal and spatial species turnover among these habitats is often high, yet little is known about how fine-scale habitat variation drives intraspecific variability in seed dormancy depth and seed germination requirements. The present study characterised seed dormancy and investigated the germination biology of six closely related herbaceous annual species of Byblis from northern Australia. We assessed variation in the response of seeds of all species to temperature cues, as well as light and the naturally occurring germination stimulants karrikinolide (KAR1) and ethylene. We also examined intraspecific variation in germination response and seed-dormancy depth for three widely distributed species with overlapping distribution occurring in habitats with differing soil thermal and hydrological conditions. Seed germination in all six species was significantly increased by exposure to either KAR1 or ethylene, with this effect being amplified in two species (B. filifolia and B. rorida) following a period of warm, dry after-ripening. Seed-dormancy depth and the germination response of seeds to both KAR1 and ethylene were partitioned more strongly among habitats than among species. Populations on shallow (<20-cm soil depth) sandy soils produced less dormant seeds than did populations of the same species on deeper sandy soils (40+ cm) or on heavy cracking clays. The upper soil profile of shallow soil habitats was exposed to higher average temperatures, greater diurnal temperature fluctuation and greatly reduced moisture persistence compared with deeper soils. Fine-scale differences in the thermal and hydrological conditions of seasonally wet habitats appear to be strong drivers of dormancy depth in seeds of tropical Byblis. Widely distributed species exhibit high levels of plasticity in seed-dormancy depth and germination response among different habitats, with similar responses being observed for sympatric species. So as to fully understand species turnover in tropical ephemerals, future studies should examine phenotypic plasticity and the rate of local adaptation of seed traits in greater detail. [ABSTRACT FROM AUTHOR]

The use of distributed temperature sensing (DTS) for ecological applications has increased rapidly in the last 6 years. Here we demonstrate the first use of DTS to measure soil temperatures during a fuel reduction burn - in an urban grassy Tuart-Banksia woodland remnant near Perth, Western Australia. Optical fibre with an acrylate material coating (diameter 242 μm), but no other jacketing or cabling, was buried in the soil at depths between 0 and 5 cm. Measurements were recorded over 316 m of optical fibre using a DTS measurement unit, providing data over a 5.5-h period at 20-s intervals; resulting in 1243 temporal measurements at 60-cm spatial resolution. Soil temperatures were calibrated to an error of ± 6.8% at 250°C. Methods for installation, calibration and data visualisation are presented. Issues associated with assessment of DTS data in a fire ecology context are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Glow‐worms are the larvae of fungus gnats that use bioluminescence to lure night‐flying insects to their webs. They are found in still, humid environments such as rainforest gullies, the vicinity of waterfalls or inside caves. Arachnocampa flava is endemic to south‐east Queensland where it is the focus of night‐time tourism at a number of subtropical rainforest locations. For management of tourist populations as well as understanding the natural dynamics of the bioluminescence display, previous studies of A. flava used photographic imaging or quadrat‐based counts to assess the number of larvae glowing. Here, time‐lapse digital photography with an SLR camera is employed in a rainforest gully to image a glow‐worm colony at 10 min intervals. Recordings took place between April and December of 2010. Blocks of continuous recording lasted 13–35 continuous days. This sampling frequency revealed the nightly bioluminescence intensity profile and the influence of some environmental conditions. On nights without rainfall, larvae initiated glowing soon after dusk, rapidly rose to a peak intensity and then progressively decreased their intensity through to dawn when they douse in response to approaching dawn. Bioluminescence output increased substantially on nights when rainfall was recorded. Use of a tipping‐bucket rain gauge at the site showed that larvae increased their intensity and the number glowing increased immediately when rain began falling. Moonlight around the time of a full moon inhibited larval bioluminescence output. The time‐lapse photographic method proved to be a useful monitoring tool that has revealed correlations between climate and season and the intensity of the glow‐worm display. [ABSTRACT FROM AUTHOR]

Abstract: Heat‐triggered fruit opening and delayed release of mature seeds are widespread among plants in fire‐prone ecosystems. Here, the material characteristics of the seed‐containing follicles of Banksia attenuata (Proteaceae), which open in response to heat frequently caused by fire, are investigated. Material analysis reveals that long‐term dimensional stability and opening temperatures of follicles collected across an environmental gradient increase as habitats become drier, hotter, and more fire prone. A gradual increase in the biaxial curvature of the hygroscopic valves provides the follicles in the driest region with the highest flexural rigidity. The irreversible deformation of the valves for opening is enabled via a temperature‐dependent reduction of the elastic modulus of the innermost tissue layer, which then allows releasing the stresses previously generated by shrinkage of the fiber bundles in the adjacent layer during follicle drying. These findings illustrate the level of sophistication by which this species optimizes its fruit opening mechanism over a large distribution range with varying environmental conditions, and may not only have great relevance for developing biomimetic actuators, but also for elucidating the species' capacity to cope with climatic changes. [ABSTRACT FROM AUTHOR]

Seed science is fundamental to many fields of endeavour, from agricultural production, to restoration, and conservation of threatened species and communities. This is especially the case in Australia which has seen hugely increased involvement and outputs from seed scientists across many sectors over the last three decades. This escalation in research is reflected in the program and outcomes of the first National Seed Science Forum that was held in March 2016 and was attended by delegates representing many scientific institutions, industry, non-government organisations and volunteer groups. There were delegates from nine countries, and keynote presentations and workshops by global leaders in seed science. A key outcome of the Forum was the unique opportunity for discussion and collaboration across sectors. Another key outcome of the Forum, the Seed Science Special Issue of the Australian Journal of Botany, captures some of the emerging topical research and themes seed scientists are working on. Of particular note is the growth in germplasm conservation of native and agricultural floras, in line with, and at the forefront of, international collaborative efforts. The other strong theme across the Forum is the increasingly sophisticated use of seeds in restoration and the enabling technological advances. Future potential advances in Australian seed science are discussed. [ABSTRACT FROM AUTHOR]

Translocation of threatened species is challenging in semiarid environments, especially when seeds are the principal means of in situ establishment. Worldwide, the overall success of translocations using seeds is highly variable and generally unpredictable. Most seed-based translocations are embarked upon with limited understanding of the species' seed biology or the nuances of the local abiotic environment in which to guide restoration approaches. For instance, within Australia just 14% of threatened species translocations use directly sown seeds and consequently, to improve the chances of restoration success, both the seed biology and the influence of the abiotic environment need to be adequately understood. Weinvestigated these aspects in Ricinocarpos brevis R.J.F.Hend. & Mollemans - a short-range Banded Ironstone endemic - by focusing on a series of laboratory and field experiments to understand the key drivers of dormancy alleviation and germination promotion, as well as in-situ conditions of natural and recipient translocation sites. Fresh seeds were found to have high viability, fully developed linear embryos and possess physiological dormancy, with enhanced germination when exposed to smoke water, karrikinolide (KAR[sub 1]) and gibberellic acid (GA[sub 3]). Under laboratory conditions, seeds germinated over a range of temperatures (15-30°C), but germination was suppressed by light and highly sensitive to water stress. Seeds had reduced germination when sown on the soil surface, but could emerge from up to 13 cm in depth. Under field conditions, in-situ emergence was <2%. Using in-situ emergence results, soil loggers and rainfall data, we developed a model of the recruitment bottlenecks faced by this species under in-situ conditions, an approach that provides useful insights to assist future translocations. Understanding seed biology and seed ecology enables better insights into the principal bottlenecks restricting in-situ emergence and consequently restoration success, leading to the development of more effective approaches for conserving other threatened flora in future. [ABSTRACT FROM AUTHOR]

The use of native plant seeds is fundamental to large-scale rehabilitation and the re-establishment of self-sustaining ecosystems after high-impact mining activity has ceased. However, many of the biological attributes of seeds are often overlooked in large-scale rehabilitation programs. Multi-disciplinary, long-term research collaborations are required to improve seed-based mine rehabilitation. In this paper, we review the steps that BHP Western Australia Iron Ore (WAIO), a large iron ore mining company that operates in the Pilbara bioregion of north-west Western Australia, has taken over the past 9 years to ensure continuous improvement in rehabilitation procedures. We introduce the mining activities that WAIO undertake in the Pilbara, and emphasise specific examples of how research findings have led to incremental improvements in the seed management cycle, growth media management and mine rehabilitation practices. Specifically, we outline how the implementation of structured seed collection and storage programs has created the capacity to maintain high-quality seed stocks sufficient for 3-5 years of future rehabilitation. Research has documented the prevalence of seed dormancy in the flora (>70% of 105 species examined produce dormant seeds), with physical and physiological classes of dormancy most commonly encountered. We discuss the development of seed-treatments such as optimised wet-heat and dry after-ripening that have increased the germination capacity of many previously dormant seed batches. In addition, we highlight how seed enhancement technologies, such as hydro-priming with smoke-derived germination stimulants and polymer seed coating, and a greater understanding of the biological and physical limitations present in the growing environment, have vastly improved seedling emergence performance under field conditions for key framework Triodia species. Ongoing industry support (e.g. construction of a purpose-built rain manipulation shelter) has ensured research in the Pilbara will continue to unpack and resolve the complex challenges associated with seed regeneration of biodiverse native plant communities after mining. [ABSTRACT FROM AUTHOR]

Background The Mantispidae are a distinctive group of Neuroptera known for the adults' possession of raptorial forelegs. There are four recognised, extant subfamilies of Mantispidae: the Mantispinae, Symphrasinae, Calomantispinae and Drepanicinae. The life history and larval behaviour of the subfamily Mantispinae is best known: the immatures are spider egg predators. Among the three remaining subfamilies, larval Symphrasinae and Calomantispinae most likely predate on other small arthropods, while the immature life history of Drepanicinae, until now, remained completely unknown. New information Here we provide observations of annual, near-synchronised, mass emergences of adults of the drepanicine, Ditaxis biseriata (Westwood), within a well-established Macadamia orchard in northern New South Wales, Australia. A female deposited fertile eggs, allowing this first report of egg batch and first instar morphology. The mass emergence of mobile pharate adults from the ground was observed in the same month in two consecutive years. The pharates climbed tree-trunks for a distance before undergoing eclosion. The newlyhatched first instar larvae are campodeiform and prognathous; a typical morphology among Mantispidae. After hatching, they drop to the ground and burrow into soil. They are unpigmented and appear to lack stemmata. Together, the observations infer that the immature component of the life cycle takes place underground in forested habitats. If this feature is common among the Drepanicinae, it might explain why so little is known of the biology of the immature stages.. [ABSTRACT FROM AUTHOR]

Demand for restoration of resilient, self-sustaining, and biodiverse natural ecosystems as a conservation measure is increasing globally; however, restoration efforts frequently fail to meet standards appropriate for this objective. Achieving these standards requires management underpinned by input from diverse scientific disciplines including ecology, biotechnology, engineering, soil science, ecophysiology, and genetics. Despite increasing restoration research activity, a gap between the immediate needs of restoration practitioners and the outputs of restoration science often limits the effectiveness of restoration programs. Regrettably, studies often fail to identify the practical issues most critical for restoration success. We propose that part of this oversight may result from the absence of a considered statement of the necessary practical restoration science questions. Here we develop a comprehensive framework of the research required to bridge this gap and guide effective restoration. We structure questions in five themes: (1) setting targets and planning for success, (2) sourcing biological material, (3) optimizing establishment, (4) facilitating growth and survival, and (5) restoring resilience, sustainability, and landscape integration. This framework will assist restoration practitioners and scientists to identify knowledge gaps and develop strategic research focused on applied outcomes. The breadth of questions highlights the importance of cross-discipline collaboration among restoration scientists, and while the program is broad, successful restoration projects have typically invested in many or most of these themes. Achieving restoration ecology's goal of averting biodiversity losses is a vast challenge: investment in appropriate science is urgently needed for ecological restoration to fulfill its potential and meet demand as a conservation tool. [ABSTRACT FROM AUTHOR]

Animals use adhesive secretions in a plethora of ways, either for attachment, egg anchorage, mating or as either active or passive defence. The most interesting function, however, is the use of adhesive threads to capture prey, as the bonding must be performed within milliseconds and under unsuitable conditions (movement of prey, variable environmental conditions, unfavourable attack angle, etc.) to be nonetheless successful. In the following study a detailed characterization of the prey capture system of the world-renowned glowworm group Arachnocampa from the macroscopic to the ultrastructural level is performed. The data reveal that the adhesive droplets consist mostly of water and display hygroscopic properties at varying humidity levels. The droplet core of Arachnocampa luminosa includes a certain amount of the elements sodium, sulphur and potassium (beside carbon, oxygen and nitrogen), while a different element composition is found in the two related species A. richardsae and A. tasmaniensis. Evidence for lipids, carbohydrates and proteins was negative on the histochemical level, however X-ray photoelectron spectroscopy confirm the presence of peptides within the droplet content. Different to earlier assumptions, the present study indicates that rather than oxalic acid, urea or uric acid are present in the adhesive droplets, presumably originating from the gut. Comparing the capture system in Arachnocampa with those of orb-spiders, large differences appear not only regarding the silky threads, but also, in the composition, hygroscopic properties and size of the mucous droplets. [ABSTRACT FROM AUTHOR]

The author discusses ecological restoration of an ecosystem through seed production in Australia. Topics discussed by the author include restoration targets of negative environmental and social factors caused by land degradation, global assessment of forest genetic resources to reinforce national seed programs for sufficient quantities of genetically appropriate seeds, and availability of seed production areas (SPA).

Ecological restoration of grasslands using wild-collected seeds is a major undertaking in many parts of the world. Impediments to effective seed use such as low seed quality, difficult-to-handle and bulky collections of seeds, and seed dormancy and germination constraints contribute to restoration failure. Native grass florets are typically irregular in shape, with appendages that impede efficient mechanized sowing and render agricultural technologies, such as the application of polymer seed coatings, impractical. Our goal was to investigate the application of a novel flaming device to remove floret appendages and improve geometry using Triodia wiseana (C.A. Gardner [Poaceae]), a key framework grass of arid ecosystems in north-western Australia, as a test species. Through the modification of a rotary seed coater with an engineered flaming apparatus, a flash flaming technique was developed. We demonstrate that flash flaming is a highly effective and efficient means of removing floret appendages and subsequently improving geometry. Once flamed, the bulk density of florets was significantly increased, the application of polymer coatings was more effective, and germination was enhanced. The improved floret geometry through flaming therefore shows promise for enhancing the mechanization of direct seeding of grasses. [ABSTRACT FROM AUTHOR]

With nearly a quarter of global dryland systems considered to be degraded, the level and scale of degradation often exceed the thresholds for autogenic recovery, requiring human intervention to ensure that ecosystem biodiversity, structure, and function can be improved. A 'Think Tank' workshop focusing on advancing the ecological approaches to large-scale restoration in degraded environments was held at Kings Park and Botanic Garden, Western Australia. Acknowledging that adaptive and broadly multidisciplinary strategies are paramount to achieving restoration in a repeatable and cost-effective manner, the workshop served as a forum to bring together plant scientists, ecologists, engineers, and environmental managers involved in dryland restoration from around the globe. This introductory paper to this special issue summarizes important contemporary challenges facing dryland restoration worldwide, offers a synthesis of the fundamental workshop themes, and provides a contextual overview for the series of invited papers in this issue, comprising reviews and case studies in seed and restoration technologies. [ABSTRACT FROM AUTHOR]

Reinstating dominant Triodia grassland communities following disturbance has been a focus of arid land restoration practitioners for decades in Australia. Yet, seed quality and variable seed germination have seriously hindered the reestablishment potential of Triodia species to date. This study set out to examine diaspore quality, germination requirements, and seed dormancy in seven Triodia species to identify first, then resolve, germination impediments. Freshly collected florets from all species were cleaned to ensure that each floret contained a viable seed and then evaluated for their initial germination capacity. Very low germination from florets (<10%) indicated the presence of physiological seed dormancy ( PD) in all species. However, germination was significantly improved (up to 57%) with the use of 0.67 µm karrikinolide ( KAR1), and to a lesser degree with 289 µm gibberellic acid ( GA3). When the covering floret structures (i.e. lemma and palea) were removed, germination increased up to 59%, which was further enhanced after exposure to GA3 (up to 66%) and KAR1 (up to 92%). Optimal germination temperatures varied from 20 to 35°C and were species specific. Dry after-ripening ( DAR −30°C and 50% relative humidity [ RH]) of florets and seeds promoted the progressive loss of PD over 12-24 months storage for most species. Germination, dormancy level, and response to incubation temperature differed amongst species, experimental units (florets and seeds), DAR treatments, and after exposure to germination stimulants ( GA3 and KAR1). For use in restoration seeding programs, careful consideration of seed pre-treatments is necessary to improve germination in Triodia species. [ABSTRACT FROM AUTHOR]

A thorough knowledge of soil functionality is critical to successful restoration of disturbed ecosystems, and its evaluation involves the assessment of soil properties and processes as a component of a healthy ecosystem. Here, we propose a set of soil quality indicators to assess the soil status in restored soils (topsoil and waste material) and test new methods that are easy to apply, interpret, and cost-effective for the analysis of soil biological indicators in restored ecosystems. We show that in addition to organic carbon and C:N ratio, biological indicators (microbial diversity and activity in particular) are the most sensitive indicators to detect differences among reconstructed soils and analogue undisturbed soils in semiarid areas. The use of the 1-day CO2 test is proven to be an alternative cost- and time-effective method to measure microbial activity and assess soil functionality of restored soils. Our results show a positive effect of vegetation on reconstructed soils and a recovery of soil functionality in waste material to levels similar to topsoil once vegetation is established. However, soil functionality in both restored waste materials and topsoils is still far from that in undisturbed native soils. We conclude that soil functionality is critical in the restoration process, particularly in semiarid areas, and the methods used here could be effectively applied in a broad range of restoration projects in arid and semiarid environments. [ABSTRACT FROM AUTHOR]

The relative effectiveness of wet- and dry-heat treatments on alleviating physical dormancy (PY) of seeds of seven species of Fabaceae and five species of Malvaceae was determined to optimise seed handling procedures for ecological restoration. Seeds of all species were treated at different temperatures (40 -- 100°C) for various durations (2 and 5min of wet heat, and 5, 10 and 30min of dry heat). Prior to treatment, seeds of all species exhibited low germination (0-38%). As hypothesised, there was variation among species with respect to the efficacy of the heat treatments. In general, wet-heat treatments at temperatures >70°C for 2 or 5 min were effective in breaking PY for all Fabaceae species, and two Malvaceae species, with resultant germination typically >75%. For dry-heat treatments, higher temperatures and longer durations were required to achieve similar germination results. In the three Malvaceae species that were least responsive to heat (Abutilon otocarpum, Hibiscus haynaldii and Sida echinocarpa), there was a trade-off between treatment temperature and duration; lower temperatures (<70°C) failed to alleviate PY, whereas higher temperatures either rendered seeds permeable but not germinable (70 -- 90°C), or resulted in seeds losing viability (e.g. 100°C). Therefore, combinational dormancy (PY + physiological dormancy) appears to be present in a proportion of the seeds of these Malvaceae species (i.e. those that imbibed and remained viable, but did not germinate). Scanning electron imagery established that the majority of wet-heat treatments resulted in the rupture of the water gap in the seed testa of all species. The results clearly demonstrate that optimal heat treatments for the alleviation of PY are species-specific. Restoration practitioners handling seeds of diverse species should be mindful of treating seeds at the lowest effective temperature (70 -- 90°C) to avoid injury through inadvertent exposure to temperatures that are higher and longer than necessary to break dormancy. [ABSTRACT FROM AUTHOR]

Despite the unprecedented global decline in extant populations of Aldrovanda vesiculosa in the last century, little is known about the reproductive biology of this iconic aquatic carnivorous plant. This study aimed to investigate the role of seed-based reproduction in the ecology of A. vesiculosa, with particular focus on the interplay between the regulation of seed dormancy by temperature cues and the efficacy of exogenous ethylene gas to act as a germination stimulant, the desiccation capacity and long-term storage potential of seeds for conservation purposes. Sexual reproduction appears to be extremely limited in both natural and naturalized populations across three continents, with high variability in the success of flowering and seed set between sites and between seasons. Overall, flowering yielded few fertile fruit (6-19% of flowers producing fertile fruit) and seed viability was variable but generally low (29-88%). Fecundity appears to be influenced by seasonal climatic conditions and microhabitat characteristics. Aldrovanda vesiculosa possesses physiologically dormant seeds, with germination stimulated by exposure to ethylene gas (>90% germination) at 25 °C. Seeds appear sensitive to desiccation and sub-zero temperature storage, with no germination and markedly reduced embryo growth after storage of seeds for >1 month at 15 °C and 15% relative humidity or after short-term (24 h) storage at −18 °C. In the absence of significant conservation and restoration initiatives, the continuing decline of dystrophic freshwater wetland habitats globally leaves A. vesiculosa facing extinction. As the successful long-term storage of seeds appears unfeasible based on the approaches described in this study, other alternatives for germplasm conservation such as cryostorage of vegetative tissues or zygotic embryos must be considered for establishing long-term ex situ collections of critical germplasm. [ABSTRACT FROM AUTHOR]

Question Freshwater rock pools ( FRP) are small, highly stressed wetland habitats that harbour many range-restricted and specialized plants. We examined the phytosociological patterns of FRP in a biodiverse monsoon-tropical region, to establish the influence of hydro-geological drivers on vegetation patterns in rock pool plant communities. Location Gardner Plateau, central North Kimberley, Western Australia (centre of the study area: 14°47′46″ S, 126°31′27″ E). Methods A total of 1066 phytosociological relevés (microplots), as well as measurements of physical habitat characteristics, were collected from 580 rock pools. Communities were classified using clustering and table sorting. The hydrological regime of each rock pool was dynamically modelled, and the most significant predicative hydro-geological factors were determined for each species and vegetation community using canonical correlation analysis, classification and regression trees and random forests. Results Variation in maximum rock pool depth, hydroperiod and the number of annual innundation events were identified as the most significant environmental predictors of community composition. All resident taxa were either regional or narrow-range endemics, with four species representing strict FRP specialists. FRP-specialist taxa exhibited the highest levels of hydro-geological specialization, and these species occurred in distinct communities characterized by longer periods of inundation and fewer annual inundation events than assemblages of non-specialist rock pool species. Eight distinct plant communities were recognized. Conclusions FRP in the monsoonal tropics are dynamic and hydrologically unpredictable aquatic ecosystems that harbour a number of unique plant communities. The duration and periodicity of seasonal inundation represent major ecological drivers of vegetation assemblages in these habitats, with inhabitant species exhibiting a progression of specialization to hydro-geological factors along a gradient of hydrological stability. Although the colonization of individual rock pools by wetland plants appears to be a random process governed by the serendipity of seed arrival events, the comparative stability of FRP over long geological time frames may have facilitated the persistence of a small number of highly specialized taxa in these ecosystems. [ABSTRACT FROM AUTHOR]

• Background and Aims Rock pools are small, geologically stable freshwater ecosystems that are both hydrologically and biologically isolated. They harbour high levels of plant endemism and experience environmental unpredictability driven by the presence of water over variable temporal scales. This study examined the hypothesis that the sediment seed bank in monsoon tropical freshwater rock pools would persist through one or more periods of desiccation, with seed dormancy regulating germination timing in response to rock pool inundation and drying events. • Methods Seeds were collected from seven dominant rock pool species, and germination biology and seed dormancy were assessed under laboratory conditions in response to light, temperature and germination stimulators (gibberellic acid, karrikinolide and ethylene). Field surveys of seedling emergence from freshwater rock pools in the Kimberley region of Western Australia were undertaken, and sediment samples were collected from 41 vegetated rock pools. Seedling emergence and seed bank persistence in response to multiple wetting and drying cycles were determined. • Key Results The sediment seed bank of individual rock pools was large (13 824 ± 307 to 218 320 ± 42 412 seeds m-2 for the five species investigated) and spatially variable. Seedling density for these same species in the field ranged from 13 696 to 87 232 seedlings m-2. Seeds of rock pool tax a were physiologically dormant, with germination promoted by after-ripening and exposure to ethylene or karrikinolide. Patterns of seed- ling emergence varied between species and were finely tuned to seasonal temperature and moisture conditions, with the proportions of emergent seedlings differing between species through multiple inundation events. A viable seed bank persisted after ten consecutive laboratory inundation events, and seeds retained viability in dry sediments for at least 3 years. • Conclusions The persistent seed bank in freshwater rock pools is likely to provide resilience to plant communities against environmental stochasticity. Since rock pool communities are often comprised of highly specialized endemic and range-restricted species, sediment seed banks may represent significant drivers of species persistence and diversification in these ecosystems. [ABSTRACT FROM AUTHOR]

Dispersal of plant propagules by ocean currents can result in long-distance dispersal and is important for the persistence of coastal species. However, the ability of such species to disperse via the ocean is often unknown because there is relatively little evidence that demonstrates that seeds or fruits can float and survive for extended periods in seawater. Furthermore, the seed or fruit traits, and intraspecific variation in these traits, that facilitate buoyancy remain largely unidentified. The genus Scaevola (L.) contains several widespread coastal species that may be capable of oceanic dispersal, such as S. crassifolia (Labill). We collected fruits of S. crassifolia along 700 km of a latitudinal environmental gradient. These fruits were used to determine the influence of fruit morphology and anatomy on fruit buoyancy. Morphological and anatomical variation in S. crassifolia was associated with dispersal potential. Our empirical data demonstrated that fruits with larger aeriferous mesocarp layers have greater buoyancy and, therefore, enhanced capacity for long range oceanic dispersal. Of three characters hypothesised to affect buoyancy (aeriferous mesocarp, air pockets in empty locules, and number of vascular cavities), only the properties of the mesocarp were significant. Intraspecific variation can significantly affect dispersal potential, and should not be overlooked in dispersal ecology. Seed dispersal is important for the persistence of plant species. Here, we investigated the amount of within-species variation in fruit morphology of a coastal species, and the effect this had on buoyancy. We found that fruits with larger aeriferous mesocarp layers had the greatest buoyancy, and therefore greater capacity for oceanic dispersal. Intraspecific variation that imparts greater buoyancy and promotes oceanic dispersal may facilitate range shifts and assist coastal species to persist through climate change. [ABSTRACT FROM AUTHOR]