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Australian temperate grasslands are among its most threatened plant communities. In agricultural landscapes, major barriers to their recovery are high soil nutrient levels that favour the growth of exotic pasture and other non-native species, high standing weed biomass creating fierce aboveground competition, and rich weed seed and bud banks providing dense emergent seedling competition. Therefore, the return of grasslands to arable landscapes through restoration must rely on overcoming these challenges, ideally by reducing soil nutrients and mitigating the effects of weeds. This study demonstrates the effectiveness of topsoil removal for restoring diverse native grassy communities by direct seeding on sites with a legacy of elevated soil nutrients and competitive exotic vegetation. Conversely, it showed that repeated shallow cultivation (four times over 12 months) to stimulate weed emergence, followed each time by herbicide application, failed to achieve this outcome, at least in the short term (three years). Grassy community restoration is imperative in Australia, but importantly, it must utilise restoration protocols that are as effective as possible so that limited time, money, and resources are not wasted. In this light, the technique of topsoil manipulation may take us one step closer to achieving this goal in agricultural locations, where their loss is most pronounced. [ABSTRACT FROM AUTHOR]

Summary: This study was conducted across twelve agricultural locations in south‐western Victoria, Australia, encompassing a range of soil types and climatic conditions. It investigated the addition of an open layer of coarse organic pine wood chip mulch (~70% surface cover) directly following direct seeding of native grassland species. The intent was to mimic positive effects of naturally occurring organic surface litter (which are typically depleted in such settings) on seedling emergence and establishment. Findings revealed negative results in that the use of an open layer of coarse pine chip mulch failed to improve native establishment at 12‐months or to moderate soil temperature and moisture extremes in comparison to non‐mulched plots. This outcome suggests the effectiveness of open surface mulches under the scenario of direct seeding may be highly site context, mulch‐type, and application approach dependent. In situations where such mulch applications are not likely to be beneficial, significant costs relating to their purchase and application could be avoided. [ABSTRACT FROM AUTHOR]

The article offers information on how ecological communities have been naturally occurring and interacting groupings of native plants and animals in a unique habitat. It mentions about the Kalbar's environmental objectives aim to minimize negative and maximize positive effects consistent with or exceeding industry practice.

Summary: This innovative roadside restoration project aimed to replace two historic non‐endemic block tree plantings with diverse native grassland. A secondary goal was to reintroduce populations of threatened species as part of the restorations (Button Wrinklewort; Clover Glycine; Hoary Sunray; and the Yam Daisy) Glycine latrobeana; Leucochrysum albicans subspr; i. The project applied what were at the time newly developed site preparation, direct‐seeding and seed production approaches designed to facilitate these outcomes. The long‐term success of these restorations (13 years) provides compelling evidence that it is feasible to restore high‐quality, low‐biomass, species‐rich native grasslands on previously exotic‐dominated roadsides. By doing so, they demonstrate that road networks offer broad canvases for restoration action and should in the future be used to create extensive native linear corridors, displaying high native biodiversity, visual and functional attributes. [ABSTRACT FROM AUTHOR]

The article offers information on the Biodiversity conservation in Australia has focused on both threatened species and ecological communities, along with conservation towards a representative set of ecosystems in the reserve network and mitigating threatening processes. In contrast, ecological restoration. It also highlights that Australia needs coordinated restoration that is integrated with conservation that includes all stakeholders to overcome any disconnect between.

The Australian native seed sector is critical for undertaking ecological restoration but faces serious challenges from interacting factors, including native vegetation loss and habitat fragmentation, low funding levels, and climate change impacts. The Australian Native Seed Survey was conducted in 2016–2017 to better understand sector structure, practitioner perceptions, and practice. It found that most native seed is collected from small and fragmented tenures and from geographic ranges that greatly exceed "local provenance"; that the diversity of species available for restoration is typically low; that native seed is seldom quality tested; and that most annual seed collections (wild or production) are small in volume suggesting overall seed yields are modest in quantity and not sufficient to support large‐scale restoration. Together, survey findings raise serious concerns about the ability of the sector, as currently constituted and resourced, to meet projected future increases in the demand for seed or for achieving the effectiveness and efficiency required to meet UN‐Decade type ecological restoration outcomes. Central to recommendations for sector improvement are the following focus areas: maturing the native seed sector; sustainability; seed production; licensing; seed testing and tracking; and research. [ABSTRACT FROM AUTHOR]

The Australian Native Seed Sector survey was conducted in 2016–2017 under the auspices of the Australian Network for Plant Conservation. Respondents self‐selected into a seed supply (Seed Collector, Seed Production Area Grower) or seed demand (Seed Purchaser, Other User) group category. Issue statements facing the sector with respect to limiting opportunities for ecological restoration were presented to survey respondents who ranked them in order of importance. Findings revealed that the order of statement importance varied depending on the primary role (Group) of the respondent in the sector. When combined across groups, the issues of most importance were: future seed demand will be difficult to meet from wild harvest; the seed market is unwilling to pay for the true cost of seed collection/seed production; there is a lack of available seed from a broad range of species; and demand for seed is inconsistent and/or unpredictable. The survey also revealed that the native seed sector is underpinned by a remarkably small and underresourced workforce, composed primarily of sole or small operators, which presents a clear concern to all users of native seed, not only in terms of current capacity for ecological restoration, but also to meet any large and rapid increases in future demand. [ABSTRACT FROM AUTHOR]

Abstract Background Integrons are genetic elements able to integrate and disseminate genes as cassettes by a site-specific recombination mechanism. These elements contain a gene coding for an integrase that carries out recombination by interacting with two different target sites; the attI site in cis with the integrase and the palindromic attC site of a gene cassette. Integron integrases (IntIs) bind specifically to the bottom strand of attC sites. The extrahelical bases resulting from folding of attC bottom strands are important for the recognition by integrases. These enzymes are directly involved in the accumulation and formation of new cassette arrangements in the variable region of integrons. Thus, it is important to better understand interactions between IntIs and their substrates. Results We compared the ability of five IntIs to carry out excision of several cassettes flanked by different attC sites. The results showed that for most cassettes, IntI1 was the most active integrase. However, IntI2*179E and SonIntIA could easily excise cassettes containing the attCdfrA1 site located upstream, whereas IntI1 and IntI3 had only a weak excision activity for these cassettes. Analysis of the secondary structure adopted by the bottom strand of attCdfrA1 has shown that the identity of the extrahelical bases and the distance between them (A-N7-8-C) differ from those of attCs contained in the cassettes most easily excisable by IntI1 (T-N6-G). We used the attCdfrA1 site upstream of the sat2 gene cassette as a template and varied the identity and spacing between the extrahelical bases in order to determine how these modifications influence the ability of IntI1, IntI2*179E, IntI3 and SonIntIA to excise cassettes. Our results show that IntI1 is more efficient in cassette excision using T-N6-G or T-N6-C attCs while IntI3 recognizes only a limited range of attCs. IntI2*179E and SonIntIA are more tolerant of changes to the identity and spacing of extrahelical bases. Conclusions This study provides new insights into the factors that influence the efficiency of cassette excision by integron integrases. It also suggests that IntI2 and SonIntIA have an evolutionary path that is different from IntI1 and IntI3, in their ability to recognize and excise cassettes.

Serratia marcescens SCH909 is a multidrug resistant strain isolated in 1988 harboring three class 1 integrons. We wondered if these integrons were retained over time and if there were other antimicrobial resistant determinants contributing to its multidrug resistant profile. Genomic analysis showed a fourth multidrug resistance integron, a Tn 7 transposon with dfrA1-sat2-ybeA-ybfA-ybfB-ybgA gene cassettes in the variable region. Insertion sequences were involved in the genesis of novel composite transposons in the L4 subtype plasmid pSCH909, such as Tn 6824 carrying an arsenic regulon and two head to head class 1 integrons surrounded by two complete IS 1. Remarkably, a novel chromosomal genomic island, SmaR, was identified, closely related to Multiple Antimicrobial Resistance Regions (MARR), usually found in AbaR0-type and AbGRI2-0 from global clones of Acinetobacter baumannii , and in M-type plasmids circulating in Enterobacteriaceae. Maintenance studies showed that the three class 1 integrons were maintained over 1 month without antimicrobial pressure. Since S. marcescens is considered a relevant nosocomial pathogen that can have a wide range of niches – human, plant, animal, soil and inanimate surfaces, our findings support the ability of this species to capture, maintain and spread a broad variety of antimicrobial resistance elements. [ABSTRACT FROM AUTHOR]

Seed production areas (SPAs) are critical infrastructure for ecological restoration, particularly in fragmented landscapes where wildland seed crops are unavailable or wildland harvest is unsustainable. SPAs are useful for a wide range of species that are amenable to cultivation. Despite increasing research on SPAs, their value for biodiversity conservation has yet to be comprehensively described. Here, we highlight the key benefits of SPAs to biodiversity conservation. First, SPAs allow restoration to be conducted on a much greater scale than could be accomplished with wildland-harvested seed, thus protecting key biodiversity assets from harvest pressures. Second, the native seed production industry adds to the base of stakeholders who are invested in restoring and enhancing biodiversity. Third, SPAs provide novel opportunities for research and public exposure to native biodiversity. We also describe how cultivation can alter plant fitness compared to wildland plants, which acts as a multiplier to their conservation implications. SPAs could lead to two interrelated negative consequences that generate risks for taxonomic and genetic diversity at multiple scales: (1) SPAs can cause and multiply negative genetic legacies as a result of cultivation practices, and (2) SPA progenies can numerically and genetically dominate wildland plant populations. Nevertheless, SPA cultivation offers an opportunity to genetically diversify SPA-derived populations for success in restoration and enlarge the pool of species available for restoration, thus mitigating or solving some of these risks. Targeted government policies toward SPAs, additional research, and sound SPA management are necessary to minimize genetic risks and taxonomic redundancy, and also to maximize the conservation benefits of SPAs. [ABSTRACT FROM AUTHOR]

The global push to achieve ecosystem restoration targets has resulted in an increased demand for native seeds that current production systems are not able to fulfill. In many countries, seeds used in ecological restoration are often sourced from natural populations. Though providing seed that is reflective of the genetic diversity of a species, wild harvesting often cannot meet the demands for large‐scale restoration and may also result in depletion of native seed resources through over harvesting. To improve seed production and decrease seed costs, seed production systems have been established in several countries to generate native seeds based on agricultural or horticultural production methods or by managing natural populations. However, there is a need to expand these production systems which have a primary focus on herbaceous species to also include slower maturing shrub and tree seed. Here we propose that to reduce the threat of overharvest on the viability of natural populations, seed collection from natural populations should be replaced or supplemented by seed production systems. This overview of seed production systems demonstrates how to maximize production and minimize unintended selection bias so that native seed batches maintain genetic diversity and adaptability to underpin the success of ecological restoration programs. [ABSTRACT FROM AUTHOR]

Grassland ecosystems across the globe have been extensively modified and degraded by agriculture and urban development, leaving conservation managers with a complex set of interacting legacies and opportunities to contend with. We advocate the use of state-and-transition models to assist conservation managers to deal with this complexity. Using a major development and compensation project as a case study (The Melbourne Strategic Assessment under the Australian Environment Protection and Biodiversity Conservation Act 1999), we discuss the uses and limitations of state-and-transition models for conservation management. We define a state-and-transition model for an endangered Australian temperate grassland. Soil and vegetation data are used to evaluate the model and confirm that the assigned states relate to observable agro-ecological patterns. We then discuss the use of this model for several different interacting purposes: as a tool for the simple communication of complex ecological processes; as a tool for landscape stratification to aid the spatial application of management and experimentation; as a framework to set and define conservation objectives; and as an aide for adaptive management. Ecosystem management is complicated by the overlapping legacies of past land uses, and the different constraints and possibilities these impose. State-and-transition models can help managers by describing these legacies and categorising the available management opportunities in a readily interpretable format. Here, we develop a state-and-transition model for an endangered grassland ecosystem, and show how it can assist management planning, monitoring, reporting and communication. [ABSTRACT FROM AUTHOR]

Summary: A restoration trial of grassy woodland on former agricultural land applied carbon at a standard rate (840 g C/m2/year) and at a high rate (4,200 g C/m2/year), to test whether further benefits to native plants and suppression of exotics would emerge. Carbon addition at the high rate reduced plant cover further than the standard rate but led to severe loss of plant species; it also reduced soil pH. Soil Al, Fe and Mn levels increased across the gradient of C addition, which would be consistent with the reduction in soil pH for Al and Mn, and a decrease in soil redox potential for Mn and Fe. Nutrient analysis of leaf tissue confirmed that uptake of Fe and Mn increased over the range of C addition, with the concentration of Mn in the high carbon treatment exceeding the threshold for toxicity for a range of species. The soil and plant tissue data are consistent with the induction of increased soil acidity and of stronger reducing conditions in the soil by high level of carbon addition and localised soil flooding. Plant uptake of Mn to toxic levels occurred subsequently, leading to negative effects on plants; aluminium phytotoxicity may also have occurred. [ABSTRACT FROM AUTHOR]

Summary: C addition has been used successfully in grassland restoration in Australia, generally as sucrose at a standard rate of 840 g C/m2/year. Previous experiments that have varied the rate of soil carbon application to reduce nitrate to favour native over nitrophilous exotic species have found that the benefits can increase over the whole range used for some native species, but only appear above particular rates of C addition for others. A restoration trial of degraded grassy woodland on former agricultural land in western Sydney combined burning and slashing to remove biomass with C addition at the standard rate, and a high rate, to reduce soil nitrate on the burnt or slashed plots. Soil was sampled for extractable nitrate, ammonium and phosphorus, and plant root simulator probes were used to measure nitrate and ammonium supply. Both extractable nitrate and nitrate supply were periodically high in the controls, at which times C addition at the standard rate significantly reduced extractable nitrate with an even greater reduction at the high rate, and resulted in negative relationships between nitrate supply and added C. Effects of added C on extractable nitrate or nitrate supply were not detectable in non‐peak periods. Extractable ammonium and ammonium supply were either unaffected or increased with added C. Colwell phosphorus showed temporal variation but was unresponsive to added C. Of the three nutrients, only the decline in nitrate matched the decline in plant cover which was lowest in value at the high carbon rate (Morris & Gibson‐Roy 2018). In the absence of added C, extractable nitrate was less than control values in the fire and slash treatments 1 year after treatment application but was similar to control values at other times. [ABSTRACT FROM AUTHOR]

The article reports about the restoration of native wildflower patches in agronomic settings for diverse and healthy pollinator populations. Topics include how angiosperms rely on animal pollinators to set seed and reproduce, thus pollination being a critical ecosystem service, underpinning plant reproductive success and, for crop species, associated yields; and how prolifically flowering native species can provide valuable floral resources for wild pollinators.

Introduction Pressure continues to grow on emergency departments in the UK and throughout the world, with declining performance and adverse effects on patient outcome, safety and experience. One proposed solution is to locate general practitioners to work in or alongside the emergency department (GPED). Several GPED models have been introduced, however, evidence of effectiveness is weak. This study aims to evaluate the impact of GPED on patient care, the primary care and acute hospital team and the wider urgent care system. Methods and analysis The study will be divided into three work packages (WPs). WP-A; Mapping and Taxonomy: mapping, description and classification of current models of GPED in all emergency departments in England and interviews with key informants to examine the hypotheses that underpin GPED. WP-B; Quantitative Analysis of National Data: measurement of the effectiveness, costs and consequences of the GPED models identified in WP-A, compared with a no-GPED model, using retrospective analysis of Hospital Episode Statistics Data. WP-C; Case Studies: detailed case studies of different GPED models using a mixture of qualitative and quantitative methods including: non-participant observation of clinical care, semistructured interviews with staff, patients and carers; workforce surveys with emergency department staff and analysis of available local routinely collected hospital data. Prospective case study sites will be identified by completing telephone interviews with sites awarded capital funding by the UK government to implement GPED initiatives. The study has a strong patient and public involvement group that has contributed to study design and materials, and which will be closely involved in data interpretation and dissemination. Ethics and dissemination The study has been approved by the National Health Service East Midlands--Leicester South Research Ethics Committee: 17/EM/0312. The results of the study will be disseminated through peerreviewed journals, conferences and a planned programme of knowledge mobilisation. [ABSTRACT FROM AUTHOR]