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.
Connecting scientific research and government policy is essential for achieving objectives in sustaining biodiversity in an economic context. Our approach to connecting theoretical ecology, applied ecology, and policy was devised using principles of restoration ecology and the requisite methodology to restore biodiverse ecosystems. Using a threatened ecological community (TEC) with >120 plant species, we posit our approach as a guide for interpreting and achieving regulatory compliance (i.e., government conditions) enacted to manage or offset environmental impacts of development. We inform the scientific approach necessary to delivering outcomes appropriate to policy intent and biodiverse restoration through theoretical and applied research into the ecological restoration of the highly endemic flora of banded ironstone formations of the Mid West of Western Australia. Our approach (1) defines scale-appropriate restoration targets that meet regulatory compliance (e.g., Government of Western Australia Ministerial Conditions); (2) determines the optimal method to return individual plant species to the restoration landscape; (3) develops a conceptual model for our system, based on existing restoration frameworks, to optimize and facilitate the pathway to the restoration of a vegetation community (e.g., TEC) using diverse research approaches; and (4) develops an assessment protocol to compare restoration achievements against the expected regulatory outcomes using our experimental restoration trials as a test example. Our approach systematically addressed the complex challenges in setting and achieving restoration targets for an entire vegetation community, a first for a semiarid environment. We interpret our approach as an industry application relevant to policy- or regulator-mediated mine restoration programs that seek to return biodiverse species assemblages at landscape scales.
Translocation of plants is used globally as a conservation action to bolster existing or establish new populations of threatened species and is usually communicated in academic publications or case studies. Translocation is also used to mitigate or offset impacts of urbanization and development but is less often publicly published. Irrespective of the motivation, conservation or mitigation, on ground actions are driven by overriding global conservation goals, applied in local or national legislation. This paper deconstructs the legislative framework which guides the translocation process in Australia and provides a case study which may translate to other countries, grappling with similar complexities of how existing legislation can be used to improve accessibility of translocation records. Each year, across Australia, threatened plants are being translocated to mitigate development impacts, however, limited publicly accessible records of their performance are available. To improve transparency and opportunities to learn from the outcomes of previous mitigation translocations, we propose mandatory recording of threatened plant translocations in publicly accessible databases, implemented as part of development approval conditions of consent. The contribution to these need not be onerous, at a minimum including basic translocation information (who, what, when) at project commencement and providing monitoring data (outcome) at project completion. These records are currently already collected and prepared for translocation proposals and development compliance reporting. Possible repositories for this information include the existing national Australian Network for Plant Conservation translocation database and existing State and Territory databases (which already require contributions as a condition of licensing requirements) with new provisions to identify and search for translocation records. These databases could then be linked to the Atlas of Living Australia and the Australian Threatened Plant Index. Once established, proposals for mitigation translocation could be evaluated using these databases to determine the viability of mitigation translocation as an offset measure and to build on the work of others to ensure better outcomes for plant conservation, where translocations occur.
Seeds are a primary source for generating plants for large-scale restoration and understanding the requirements for seed germination and establishment is fundamental to ecological restoration. Seed germination traits are central to defining the germination niche and identifying traits that may limit seedling establishment provides insights into how seeds may interact with the abiotic environment and the soil substrates specific to each restoration site and informs seed management practices. In this paper we review seed trait data derived from research to improve restoration practice across diverse ecosystems within Western Australia. We compile and evaluate seed trait data for up to 300 seed collections of 287 species that are used in restoration programmes to identify species, lifeform, and region-specific variation in seed dormancy, maximum germination, germination speed, base water potential, and germination niche breadth. Through a synthesis of this data, we outline our ecologically-guided approach to identifying key seed traits that support plant regeneration to improve the success of seed-based restoration across the biodiverse Western Australian landscape.
SummaryQuantifying ecological interactions can inform restoration practitioners of the recovery of ecosystem function in restored areas. Plant–animal interactions that move seeds are critical for plant recruitment, animal food sources and ecosystem function, but seed movement immediately after sowing can affect calculations of seedling emergence in restored areas. We set up seed cafeterias in undisturbed, native vegetation and restored areas to quantify and compare the removal of seeds of eight native plant species of banded ironstone ranges to determine the recovery of this ecological interaction and the potential effect on monitoring protocols. Overall, the average amounts of seeds removed from cafeterias over two days were between 17 and 23%, but this varied considerably between replicates. Seeds with or without a food body (i.e. elaiosome) were both removed from cafeterias by invertebrates. Seeds removed by invertebrates (most likely ants) after surface sowing for restoration are expected to negatively affect calculations of seedling emergence because the known quantity of sown seeds has been reduced, deflating emergence calculations. Restoration protocols should consider the potential negative effect of seed movement on seedling emergence. Encouragingly, these restoration areas have maintained ecological interactions that move seeds in the landscape at comparable levels to undisturbed vegetation.
Soil moisture and physical characteristics strongly influence plant-available water and surface crust strength, which affect seedling emergence. We test interactions between rainfall amount and topsoil and waste rock blends and their impact on restoration outcomes in a semi-arid environment. Seedling emergence was evaluated in eight species across three winter rainfall treatments (low (ambient) 68 mm, equivalent to 1st decile; median 144 mm; and high 182 mm, 8th decile) and three soil cover treatments (topsoil, waste rock and topsoil+waste rock blend (3:1)) to assess the effect of rainfall amounts, soil cover blend, and their interactions on plant recruitment in restoration. Seedling emergence for all species was <1% under the low winter rainfall (i.e. deficit) and significantly higher (1-5%) for median and high rainfall scenarios. Soil covers that included topsoil had nearly 3-times more seedling emergence than waste rock cover. Thus, restoration success can be significantly hampered in years with below median rainfall. When rainfall conditions were favourable, however, blended soil covers performed similarly to topsoil covers, and may be a useful approach for restoration when topsoil is a limited resource.
We have just experienced the most extensive fires ever recorded
Aims This study investigated the effect of method of blending and spreading topsoil-waste rock (as dictated by waste dump position), rock addition, topsoil source and seed burial on seedling emergence from seeds broadcast onto mine restoration sites. Methods Seed of 10 species were surface sown onto a waste rock dump plateau with six cover treatments spread by loose tipping; three topsoil source treatments (sand dunes, sandplains and stony hills) x two waste rock treatments (topsoil mixed and without waste rock). Results Emergence was greater on the waste dump plateau than slopes, where very few seedlings emerged. On the waste dump plateau, the addition of rock to topsoil increased seedling emergence >2.5-fold. Soil surface temperatures were cooler and water content at a depth of 2 cm was higher in topsoil mixed with rock than without rock. Conclusions Higher seedling emergence with the addition of rock to topsoil was due to the creation of microsites where sub-soil moisture was retained for longer durations. Lack of emergence on waste dump slopes was attributed to relatively low surface roughness that reflected operational issues associated with different methods of spreading and mixing topsoil with rock on plateau versus on slopes.
We investigated the diversity and composition of bacterial communities in rhizospheric and non-rhizospheric bulk soils as well as root nodule bacterial communities of Vachellia pachyceras - the only native tree species existing in the Kuwait desert. Community fingerprinting comparisons and 16S rDNA sequence identifications were used for characterization of the bacterial population using specific primers. The bacterial characterization of soil samples revealed four major phyla: Acidobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. In situ (desert) samples of both rhizospheric and non-rhizospheric bulk soil were dominated by the bacterial phyla Firmicutes and Bacteroidetes, whereas the phylum Betaproteobacteria was present only in non-rhizospheric bulk soil. Ex situ (nursery growing condition) V. pachyceras resulted in restricted bacterial communities dominated by members of a single phylum, Bacteroidetes. Results indicated that the soil organic matter and rhizospheric environments might drive the bacterial community. Despite harsh climatic conditions, data demonstrated that V. pachyceras roots harbor endophytic bacterial populations. Our findings on bacterial community composition and structure have major significance for evaluating how Kuwait's extreme climatic conditions affect bacterial communities. The baseline data obtained in this study will be useful and assist in formulating strategies in ecological restoration programs, including the application of inoculation technologies.