Context Biological invasions diminish the structures of ecosystems and biological functions. In this regard, Cyperus aromaticus (Cyperaceae) (Navua sedge), a native of Africa, recently established along the coastal regions of far north Queensland (FN-QLD), Australia, forming extensive monospecific stands and affecting both agricultural and natural landscapes.Aims This study examined the changes in soil physico-chemistry and differences in plant tissue chemical profile of C. aromaticus and its co-occurring pasture species in invaded landscapes of varying land-use types.Methods Across many C. aromaticus invaded sites in FN-QLD (N = 14), we collected above-ground vegetation and soils in invaded and nearby non-invaded patches. We also set up a microcosm trial in which C. aromaticus and a desirable pasture grass species (Urochloa humidicola) were grown individually in potted soils, and changes in soil chemistry were monitored for 3 years.Key results Neutral effects of C. aromaticus invasion were detected in soils of active agricultural lands, but significant differences occurred in other land-use types (roadside, riparian corridor, abandoned agricultural land) and in the microcosm trials. The plant tissues of C. aromaticus are higher in many micronutrients (e.g. sulfur, copper, aluminium, iron, zinc) than those of co-occurring pasture species. Significantly higher lignin concentration, but lower forage quality of fibre, cellulose, and hemicellulose were also detected in C. aromaticus.Conclusions C. aromaticus invasion is associated with changes in soil processes and systems, but its effect can be obscured by land-use (e.g. anthropogenic) practice. In invaded landscapes, the changes in soil chemistry and observed differences in tissue composition between C. aromaticus and co-occurring pasture grasses might lead to positive plant-soil feedback, thus promoting the establishment and further spread of the weed. Additionally, the lower forage quality of C. aromaticus reinforces the need to manage the weed, especially in grazing landscapes.Implications These findings highlight the capacity of C. aromaticus weed to modify soil processes and ecosystem functions, reinforcing its threat to both ecological integrity and agricultural productivity in north-eastern Queensland.

The sustainable management of almond (Prunus dulcis) hulls and shells represents a major challenge for the global almond industry. Although almond hulls possess considerable nutritional value and can be used as livestock feed, concerns about pesticide residues limit their utilisation and pose environmental and economic disposal challenges. Therefore, alternative crop protection strategies that reduce reliance on chemical pesticides while maintaining productivity are required. Silicon has been widely reported to enhance plant resistance against biotic and abiotic stresses, improve nutrient utilisation, and increase crop productivity. This study evaluated the effects of an enhanced potassium silicate formulation applied through fertigation on pest and disease incidence, plant performance, and kernel yield in a commercial almond orchard over two consecutive growing seasons. The formulation contained potassium silicate (50% w/v), amino acids (42% w/v), Complex Polymeric Poly-Hydroxy Acid (CPPA) (1.5% w/v), and water. Treatments were applied twice per season at a rate of 30 L ha−1 and compared with a grower-standard management program. Silicon-treated trees exhibited significantly lower levels of microbial disease damage in both leaves and mature nuts compared with untreated controls. Across the two growing seasons, pest- and disease-related damage to nuts was reduced by up to 59%. Silicon treatment also resulted in substantial increases in oven-dried kernel weight, ranging from 19% to 33% across the evaluated almond varieties. No adverse effects were observed on flower-to-nut conversion, chlorophyll content, kernel nutritional quality, or leaf nutrient status. The findings demonstrate that enhanced potassium silicate fertigation can improve pest and disease resistance while increasing kernel yield in commercial almond production systems. The technology offers a promising strategy for reducing reliance on chemical pesticides and supporting the sustainable utilisation of almond by-products, including their use in livestock feed and bioenergy production.

Introduction A key barrier when restoring arid ex-grazing land is the presence of artificial watering points (AWPs). Even after the cessation of domestic livestock grazing, AWPs support high numbers of wild herbivores and sustain high grazing pressure, suppressing plant species establishment. One approach to reducing total grazing pressure is to decommission AWPs; however, it is unclear how this impacts vegetation and groundcover recovery, or the efficacy of different closure methods.Objectives This study aimed to assess the impact of AWP closure methods on vegetation and groundcover in relation to distance from AWP, time, and rainfall.Methods In this 9-year study on ex-grazing land now managed for conservation, AWPs were experimentally closed using three closure methods, plus AWPs left "open" as controls. Vegetation and groundcover were measured at increasing distances from AWPs each year.Results Two years of extremely high rainfall resulted in a reversal of the piosphere effect at all AWPs regardless of closure treatment. Bare ground consistently decreased over time, and native plant cover in dunes increased. The treatment effects close to AWPs were confounded by disturbance effects, particularly at AWPs where earthmoving redistributed the soil profile.Conclusions Our results reflect the broader recovery of an ecosystem on a restoration trajectory, where outcomes have manifested after a high rainfall period. Uncertain results from this work and other AWP closure studies reflect the challenges in designing AWP closure studies at ideal spatial and temporal scales.

Pontederia (= Eichhornia ) crassipes Mart (water hyacinth) is an aquatic, free-floating, perennial plant that has been described as one of the most destructive and invasive species in the world. Whilst it is native to South America, P. crassipes can now be found in all habitable continents, which has been a result of its aggressive and rapid growth pattern, assisted by the global ornamental pond plant trade. Of particular concern, is that the spread of P. crassipes is projected to increase as a result of anthropogenic factors, climate change and inappropriate or unsuccessful management interventions. To assist in this area, this review explores the biology and ecology of P. crassipes with an aim of identifying the current most suitable methods of control, whilst also highlighting key areas of research that can help facilitate future management of the species. To combat its invasive habit, a range of control options have been tried, including biological, chemical and mechanical strategies, but many of these options have shown varying levels of effectiveness, particularly when used in isolation. In addition, the successful management of P. crassipes is largely determined by specific enabling conditions, such as (i) climatic and environmental elements, (ii) cooperation of relevant authorities and local communities, (iii) infrastructure and resource availability, (iv) national and local regulations and (v) the availability of skills and knowledge. As a result, managing P. crassipes requires an integrated approach and appropriate phytosanitary measures to prevent its spread and introduction to new areas, which is further discussed within this review.

Cyperus aromaticus (Ridley) Mattf. & K & uuml;k. (Navua sedge) is an aggressive perennial weed threatening pasture systems, sugarcane production, and roadsides in Queensland's wet tropical regions. This study assessed the efficacy of seven herbicide programs: (i) halosulfuron-methyl (single and multiple applications), (ii) Halosulfuron-methyl (multiple applications-four times), (iii) Halosulfuron-methyl (single application) followed by glyphosate spray (6 weeks after Halosulfuron application), (iv) Paraquat (single application) followed by three applications of Halosulfuron-methyl, (v) Imazapyr (single application), (vi) Imazapyr (multiple applications-four times), (vii) Florpyrauxifen-benzyl (multiple applications-four times), and (viii) an untreated control. Treatments were applied at two plant growth stages (post-mowing and flowering) across three land-use types: pasture (Malanda), sugarcane (Gordonvale), and roadside (Ingham). Weed kill percentage and tiller density were evaluated at 6, 12, and 18 months after the first herbicide application. When treatments were assessed 6 months after the first herbicide application, Imazapyr, performance averaged over the three locations in mowed plots either as a single or multiple application, resulted in poor weed control (3%-8% control); however, it showed improved performance (32%-42% control) when applied in non-mowed plots. At 6 and 12 months after the first herbicide application, multiple applications of florpyrauxifen-benzyl applied four times delivered the highest and most consistent control (77%-91%) and significantly reduced tiller production. Sequential applications of halosulfuron-methyl with glyphosate or paraquat provided effective early-stage control. Single applications of imazapyr or halosulfuron-methyl were ineffective (3%-20%) and linked with high tiller density. Six months after the first herbicide application, sequential applications of halosulfuron-methyl followed by glyphosate, and paraquat followed by halosulfuron-methyl, also provided effective weed control. In contrast, single applications of imazapyr or halosulfuron-methyl provided poor control (3%-20%) at this time and were associated with higher tiller counts. By 18 months after the first herbicide application, averaged over locations and herbicides, mowed plots achieved higher weed control (29%) and resulted in less tiller production than those at the flowering stage (20%). Further, when averaged across location and application stage, no herbicide achieved more than 34% control. Additionally, averaged over herbicides and application stage, the roadside site had better weed control (56%) than the sugarcane (11%) and pasture (7%) sites. This study highlights the importance of multiple herbicide applications, particularly halosulfuron-methyl or florpyrauxifen-benzyl applied in mowed plots for long-term suppression of C. aromaticus.

ABSTRACT Calotropis procera and C. gigantea are emerging as globally invasive plants that can significantly alter ecosystems in areas where they have escaped from attended cultivation. Without effective management, these species can form dense monospecific stands, resulting in severe economic, environmental and social impacts. Current control measures for these species are often limited in effectiveness, especially when applied as single‐use approaches. To address this issue, this review synthesises key biological and ecological traits, current and potential invasion dynamics and management options available for C. procera and C. gigantea . Although more detailed investigation is required in some areas, it appears that an integrated approach is emerging as a possible option. Such an approach should consider (i) early detection and preventative strategies, including creating and maintaining competitive pastures and reducing soil disturbance, (ii) biological control, with the potential development and release of host‐specific insects and plant pathogens, (iii) chemical control with diverse modes of action, (iv) physical control including manual removal of all plant propagules from the soil and (v) ecological burn programs to remove the aboveground biomass followed by chemical or physical interventions. It is anticipated that the implementation of these strategies is likely to significantly mitigate the impacts posed by established C. procera and C. gigantea stands, while also addressing and removing newly emerging individuals before they develop robust populations.

Almond (Prunus dulcis) production generates large quantities of hull by-products, the safe utilisation of which can be affected by pesticide residues resulting from conventional disease management practices. Identifying practical approaches that reduce pesticide use while maintaining crop health is therefore an important step towards more sustainable almond production. This study evaluated vitamin-based biostimulants as a potential alternative disease management strategy under commercial orchard conditions. Field experiments were conducted over two consecutive growing seasons in commercial almond orchards in Australia. Eight vitamin formulations containing vitamin B complex, vitamin B1, vitamin C and vitamin E were evaluated for their ability to reduce disease incidence in leaves and whole nuts, together with their effects on chlorophyll content, flower-to-nut conversion, kernel nutrient composition and other production-related parameters. A formulation containing 50 µg mL−1 vitamin B complex together with vitamin B1 consistently reduced disease incidence to levels comparable with the grower standard chemical programme. Selected vitamin treatments also maintained chlorophyll content, kernel nutrient composition and flower-to-nut conversion without adversely affecting crop performance. Overall, the results indicate that vitamin-based biostimulants have the potential to become a practical component of integrated disease management in commercial almond production. Their use may contribute to reducing reliance on conventional pesticides while supporting the sustainable utilisation of almond hull by-products and improving the environmental sustainability of almond production systems.

Invasive species pose major global threats to ecosystems and agriculture. Serrated tussock (Nassella trichotoma) is a highly competitive invasive grass species that disrupts native grasslands, reduces pasture productivity, and increases land management costs. In Victoria, Australia, it presents a major challenge due to its aggressive spread and ecological impact. While current ground surveys and subsequent management practices are effective at small scales, they are not feasible for landscape-scale monitoring. Although aerial imagery offers high spatial resolution suitable for detailed classification, its high cost limits scalability. Satellite-based remote sensing provides a more cost-effective and scalable alternative, though often with lower spatial resolution. This study evaluates whether multi-temporal Sentinel-2 imagery, despite its lower spatial resolution, can provide a comparable and cost-effective alternative for landscape-scale monitoring of serrated tussock by leveraging its higher spectral resolution and seasonal phenological information. A total of eleven models have been developed using various combinations of spectral bands, texture features, vegetation indices, and seasonal data. Using a random forest classifier, the best-performing Sentinel-2 model (M76*) has achieved an Overall Accuracy (OA) of 68% and an Overall Kappa (OK) of 0.55, slightly outperforming the best-performing aerial imaging model's OA of 67% and OK of 0.52 on the same dataset. These findings highlight the potential of multi-seasonal feature-enhanced satellite-based models for scalable invasive species classification.

Differences in the ecological stability of shallow lakes are reflected in the functional nature of the distinct phytoplankton communities in the Southern Hemisphere. Recent studies have highlighted growing uncertainties of the previous concepts regarding phytoplankton cosmopolitanism, suggesting these communities may be more regionally specialized. Consequently, the generalized applicability of traditional Northern Hemisphere-derived limnological principles can be challenged when applied to aquatic vegetation in the Southern Hemisphere. In this respect, informed comparisons among Southern Hemisphere phytoplanktonic community structures, trophic interactions and influence of submerged aquatic vegetation (SAV) on shallow lake are currently lacking. To redress this knowledge gap, a synthesis of available literature from inland water bodies of the Southern Hemisphere, including Antarctica, Australia, New Zealand, South Africa and South America, has been consolidated in this review to guide future research directions. Further, unique characteristics of Southern Hemisphere phytoplankton and SAVs, driven by global climate change and a multiplicity of anthropogenic stressors, require specific investigation to establish how such impacts have likely contributed to the observed endemic outcomes. The biogeographic framework and interactive—functional model to understand the complex interaction of factors contributing to alternative stable states in these freshwater systems has been represented.

Without appropriate and ongoing management interventions, weeds will continue to economically and environmentally disadvantage agricultural and natural ecosystems. For these management strategies to have long‐term sustained success, they need to carefully consider the biological aspects of the targeted weed. These strategies will also need to consider potential adaptations evolved by the targeted weed in response to a range of selection pressures imposed by anthropogenetic factors, climate change, changing environmental conditions, and inappropriate or unsuccessful management regimes. One group of weeds that has been observed to readily adapt to a wide range of conditions and has shown considerable challenges in their management is invasive grasses. Adding to these challenges is that several invasive grasses have also developed resistance to a range of herbicide modes of action, which, to date, has been one of the most commonly used methods of control. To address these challenges, this review explores the biology and ecology of the globally invasive annuals Echinochloa crus‐galli (Barnyard grass) and Panicum capillare (Witchgrass), and the perennial Sorghum halepense (Johnson grass) to identify (i) the most suitable management options for their control and (ii) potential research gaps that may assist in the future management direction of these species. Based on the findings of this review, it is clear that an integrated management approach that targets different aspects of the plant's biology, in combination with early detection and treatment and ongoing surveillance, is necessary for the long‐term control of these species. Although a combination of methods appears promising, further investigation still is required to evaluate their efficiency and long‐term success in a changing environment, all of which are further discussed within this review.

Eucalyptus costata is a widespread eucalypt species used in restoration works. It is common to the Mallee, a vegetation type in the semiarid temperate region of southern Australia, characterised by hot summers and mild winters, generally reliable but highly variable rainfall, and nutrient poor soils composed primarily of sands. An understanding of the germination biology of Eucalyptus costata may assist in its successful establishment. We studied the impacts of light, temperature, salinity, moisture and sowing depth on the germination of E. costata in the laboratory and considered the results in a restoration context. Germination was lowest under the highest temperature regime (35°C/25°C), high salt concentrations (>100 mM) and low water potentials (taking 14 MPa of humidity per day to germinate). Sowing depths greater than 2 cm reduced seedling emergence. These results suggest that E. costata’s germination requirements are shallow sowing in low salinity soils during periods of cool or mild wet weather, consistent with winter and spring planting.

Restoration of arid vegetation is an essential and difficult task, making the selection of the right methods for restoration an important choice. One way to determine which methods would be most effective is by accessing the accumulated knowledge of restoration practitioners, which is often unreported in the scientific literature. This study created an online survey asking questions of practitioners on the effectiveness of different methods for arid restoration, including how effective they are at promoting restoration and their financial and labour inputs. The survey was distributed to arid restoration practitioners within Australia, with a focus on the southern areas, and found that the methods most commonly used are ones that appear most effective at promoting restoration and are generally the most highly recommended. The cost and labour input did not correlate with the most used or most recommended method, suggesting that these are secondary factors and are not necessarily the most important concerns for the survey respondents. While mechanical direct seeding was indicated to have lower financial and labour inputs, both it and hand-planting were indicated to be similar in restoration ability and were both highly recommended. Grazing control methods and chemical weed control were also indicated to be effective at restoration, likely due to damage that grazing and weed competition can inflict upon plantings. Pre-seeding treatments were found to be both effective at restoration and have low labour and cost requirements, making them one of the most highly recommended methods. Soil amendments, such as water-holding gels and biochar, despite being low-to-moderate in terms of cost and labour input, were not indicated to be effective at restoration and were subsequently not highly recommended. Though some general trends could be found, respondents also commonly pointed out that the choice of methods will often depend on the site-specific conditions.

Direct seeding is a potentially valuable method for restoration in arid areas due to its low cost and labor input but suffers from the drawback of reduced survival rates, which may lead to planting failure. As such, the addition of soil amendments may be one way to increase planting success rates. This study investigated whether the addition of three types of soil amendments (fertilizers, hydrogels, and microbial inoculants) would be able to increase the emergence and survival times of direct seeding works in the semiarid Mallee region of north‐west Victoria, Australia. Seed from four native species were mechanically directly seeded into three sites across the Mallee region, along with different combinations of soil amendments. Emergence and survival time were recorded for 1 year, and the soil properties at each planting location were analyzed. The results showed that only the two larger‐seeded species ( Acacia ligulata and Callitris gracilis ) were able to emerge, while the two smaller‐seeded species ( Eucalyptus calycogona and Melaleuca lanceolata ) showed no emergence. Soil amendments had no effect on either seedling emergence or survival time. Instead, seeding location had a significant outcome for both seedling emergence and survival. It was found that locations that showed the highest emergence did not necessarily show the highest survival. Low soil nutrient sandplains contained the highest seedling emergence counts. The longest surviving seedlings were in locations with slightly higher nitrogen levels for A. ligulata seedlings, while C. gracilis survived longest in highly sandy soil under a slightly cooler, wetter climate.

Grassland reserves are vital for biodiversity and climate mitigation. Remote sensing imagery is increasingly being used to monitor vegetation health and invasive species in these vast areas. However, the spectral sparsity and mixed pixels of Sentinel-2 limit its capacity for accurate unmixing. Existing linear and deep learning methods, designed for hyperspectral imagery, cannot fully utilise the limited spectral bands and spatial information of Sentinel-2, leading to poor unmixing results. In this paper, we propose the Multi-Feature Unmixing Network (MFU-Net) - a deep learning architecture designed for Sentinel-2 unmixing. MFU-Net employs a dual-branch network that fuses spatial and spectral features through a CBAM attention mechanism and an iterative Attentional Feature Fusion (iAFF) block for adaptive integration. Our results show that MFU-Net outperforms the linear model, reducing RMSE by about 30.3% while improving $R^{2}$ from 0.0046 to 0.5234. MFUNet also outperforms a state-of-the-art deep learning method: the Multi-Feature Extraction, reducing RMSE by 2.56% and improving $R^{2}$ by 5.16%. Ablation study also confirms that spectral CBAM and iAFF module are key contributors to the relatively improved performance.

Almonds are universally recognised as a highly nutritious and economically valuable edible nut. However, the 2023/2024 global Almond production of 1.51 million metric tons generated a significant amount of waste, mainly in hulls, totalling about 5.03 million metric tons. Addressing the sustainable disposal of this waste is crucial to ensuring the industry's long-term viability. Whilst Almond hulls are a valuable source of crude protein and dietary fibre for livestock feed, when using them as feed for dairy and beef cows, it is essential to consider the possibility of carry-over pesticide residues resulting from chemical pathogen control during production. These residues have the potential to enter the food chain and appear in dairy and beef products. This study tests the hypothesis of using natural caffeine as a replacement for chemical pesticides, which could help to reduce the chemical residue levels in Almond hulls. There were three different concentrations of caffeine, 0.01, 0.1, and 0.5 % (w/v), used as foliar applications for three common Almond varieties. Caffeine treatments have been found to effectively control Almond fungal diseases like Hull Rot and Shot-Hole in commercial agriculture production, and they also show some effectiveness in reducing damage from insect pests. The treatments have been shown (i) to have a positive impact on increasing kernel weights and enhancing nut sets, not significantly affecting the plant's absorption of nutrients or the distribution of plant nutrients, and (iii) they have a neutral effect on leaf chlorophyll levels. These results indicate the potential of caffeine to address pesticide Maximum Residue Limit (MRL) issues and support its use in combination with suitably Integrated Pest Management (IPM) approaches.

Australia is home to a rich assemblage of samphires (Tecticornia and Salicornia spp.) which are largely endemic, inhabiting saline and semi-saline areas across climatically diverse regions. While these plants are adapted to harsh conditions, they are vulnerable to the effects of climate change which is anticipated to exacerbate existing management and environmental pressures. Despite the threatened and priority status of many samphires, there is an overall lack of knowledge surrounding their distribution, ecology and responses to environmental threats, data which we believe is critical to support their conservation and management. We have compiled and critically assessed peer-reviewed and online grey literature and databases to provide an overview of threatened and poorly known samphires in Australia, with particular reference to their distribution, threats and ecological responses. Of the 58 species and 19 subspecies recorded in Australia, two are federally listed as threatened, eight have a formal conservation listing in at least one state or territory, and 25 are recognised as data deficient or priority taxa. Five samphire communities are also listed as threatened and seven are considered Priority Ecological Communities. We found gaps in data relevant to these threatened and priority species, with 40

Direct seeding of restorative plants is a difficult task in arid environments due, in part, to the low moisture levels inherent to these areas. This barrier to restoration has stimulated a number of methods to help combat this issue, including the burial of seeds just below the soil surface, the addition of fertiliser and the use of other suitable low-cost soil amendments aimed at improving germination and survival. This study examines the effects of burial depth and application of soil amendments on seedling emergence under different watering regimes on four semi-arid zone species. The soil amendments used were hydrogel (EarthCare Water Crystals), fertiliser (Osmocote), and a commercial soil microbial inoculant (Bactivate5). It was found that, while heavier seeded species were able to emerge from deeper below the soil surface, all seeds in the study preferred to emerge from shallow burial depths of around 6-10 mm. Soil amendments were shown to have minimal effect on emergence rates, regardless of the watering regime, while the watering regime was found to have the largest impact. Seedlings under a low watering regime (30% water holding capacity) were found to have the lowest emergence rate, while a moderate watering regime (55% water holding capacity) produced the highest emergence across most species. Results obtained from this study suggest that shallow burial of seeds 6-10 mm below the soil surface, as opposed to surface placement or deeper burial, may enhance emergence for the species tested. Although the soil amendments did not improve plant species emergence, amendment application may still be beneficial for developing seedlings by enhancing seedling resilience to adverse growing conditions such as moisture stress or extreme temperatures.

Over the recent years, airborne Light Detection and Ranging (LiDAR) data has been used to detect the egg incubators (a.k.a. mounds) of Malleefowl on large conservation areas. However, the mound detection accuracy of the existing automated methods is not high enough to be implemented in the field. To improve the detection accuracy, this paper focuses on the mound and its habitat-based feature extraction and classification, using the distinctive geometric behaviour of and surrounding the mound. We propose a novel feature extraction method of mounds, which leverages the slope of the ground with a planar terrain model (a.k.a. the ground plane) obtained by least squares plane fitting of the ground points. By observing the features based on the ground plane, we extract structural and habitat features, and group the mound-like ground points using clustering. Finally, we apply several binary classifier models to detect areas with mounds, among them Medium Gaussian SVM performs the best (around 95 % accuracy). Our training and testing datasets contain LiDAR point cloud data captured from the Tarawi Nature Reserve by the New South Wales Government in Australia.

Arid environments have become degraded in recent times through human activity highlighting the need for restoration works to reverse this trend. One of the most common forms of restoration works is revegetation. However, revegetation is difficult in the arid zone due to a combination of environmental factors such as low moisture and extreme temperatures, as well as financial and administrative factors. In this review, we investigated the literature describing various methods available for arid revegetation, and assess their utility for revegetation activities. Each of the methods investigated were found to have potential advantages and disadvantages, though some general trends were observed. Two main planting methods were identified, “out‐planting” and “direct seeding.” Which of these methods to use depends on the conditions of the project being undertaken. Out‐planting appeared to be the most suited approach to smaller scale projects with higher budget availability, whereas direct seeding was more suited to large scale, lower budget projects. Weed control prior to planting was identified as being critical for success in most works, whereas soil ripping was beneficial for direct seeding projects. Among the soil amendments investigated, water‐holding gels were most likely to be beneficial, whereas fertilizers were riskier due to their potential to reduce drought tolerance and increase weed invasion. Microbial inoculation with mycorrhiza showed high potential to improve plant performance but may be held back by the lack of suitable commercial sources. Newer seed technologies, such as synthetic seed coats and pellets, show promise, but this issue still requires further research and development.