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We assessed the impact of road disturbances on the dominant mycorrhizal types in ecosystems at the global level and how this mechanism can potentially lead to lasting plant community changes. We used a database of coordinated plant community surveys following mountain roads from 894 plots in 11 mountain regions across the globe in combination with an existing database of mycorrhizal–plant associations in order to approximate the relative abundance of mycorrhizal types in natural and disturbed environments. Our findings show that roadside disturbance promotes the cover of plants associated with arbuscular mycorrhizal (AM) fungi. This effect is especially strong in colder mountain environments and in mountain regions where plant communities are dominated by ectomycorrhizal (EcM) or ericoid‐mycorrhizal (ErM) associations. Furthermore, non‐native plant species, which we confirmed to be mostly AM plants, are more successful in environments dominated by AM associations. These biogeographical patterns suggest that changes in mycorrhizal types could be a crucial factor in the worldwide impact of anthropogenic disturbances on mountain ecosystems. Indeed, roadsides foster AM‐dominated systems, where AM‐fungi might aid AM‐associated plant species while potentially reducing the biotic resistance against invasive non‐native species, often also associated with AM networks. Restoration efforts in mountain ecosystems will have to contend with changes in the fundamental make‐up of EcM‐ and ErM plant communities induced by roadside disturbance. [ABSTRACT FROM AUTHOR]

There has been extensive commentary about historical First Nations' land management in Australia, including in tall, wet forests, and therefore their condition at the time of the British invasion in 1788. Popular texts have interpreted records kept by early British invaders to argue that extensive areas of tall, wet forest were kept open through frequent burning by the First Peoples. However, these interpretations conflict with historical and ecological evidence, which is rarely acknowledged in public discourse. Here, we present evidence about what Victorian Mountain Ash (Eucalyptus regnans) forests were like at the time of the British invasion. We show that at the time of the British invasion, most areas of mainland Mountain Ash forests were likely to have been naturally dense and wet, with: (1) overstorey trees spaced relatively widely; and (2) an understorey consisting of a cool temperate rainforest mesic layer. Ecological and physiological evidence suggests that Mountain Ash forests evolved under conditions where high‐severity wildfire was comparatively rare, leading to patterns of landscape‐level cover dominated by relatively mature forests. This is broadly consistent with reports from the First Peoples, early historical accounts, paintings, and photographs. These forests were not open or park‐like, as may have been the case in some other Australian vegetation types. However, these forests were not wilderness, but places of significance to the First Peoples. Understanding forest structure at the time of the British invasion is critically important in establishing historical reference conditions for guiding appropriate restoration programmes, especially the reinstatement of traditional ecological knowledge, after long periods of post‐British invasion disturbance and degradation. Notably, the dense, wet understorey that characterizes Mountain Ash forests should be recognized as an inherent and entirely natural part of the ecological dynamics of this ecosystem, with approaches to thin, burn, or remove it highly likely to be counterproductive and have a range of detrimental environmental effects. [ABSTRACT FROM AUTHOR]

Understanding why some, but not other, plant communities are vulnerable to alien invasive species is essential for predicting and managing biological invasions. Darwin proposed two seemingly contradictory hypotheses on how native‐invader relatedness influences invasion success, emphasizing, respectively, the importance of environmental filtering and competition between natives and invaders. Despite much recent empirical research on this topic, reconciling these two hypotheses, known as Darwin's naturalization conundrum, remains a challenge.Using plot‐level data from natural forests along elevational transects covering strong environmental gradients, we examined whether the invasion of the globally invasive species crofton weed (Ageratina adenophora) can be explained by environmental filtering and/or competition from closely related species linked to environmental gradients.Abundant precipitation, warm temperatures, open canopies and postfire environments facilitated A. adenophora invasion, whereas resident taxonomic richness suppressed its invasion. Importantly, we found that invader‐resident relatedness had a strong negative effect on invader cover under resource scarcity conditions (e.g. low water availability), but not under non‐resource environmental stress gradients (e.g. low temperature).Synthesis and applications. Our results suggest that the impact of species phylogenetic relatedness on invasion success varies distinctly along resource versus non‐resource environmental gradients. These results help to reconcile Darwin's naturalization conundrum, thereby improving the ability to predict the success of alien plant invasions in a changing world. Our study stresses the need to consider adjusting forest species composition to strengthen their resistance to invasion, while taking into account resource and non‐resource environmental gradients, particularly after wildfires. [ABSTRACT FROM AUTHOR]

A combination of ecophysiological features makes some invasive plants difficult to eradicate in Mediterranean-type ecosystems. The human footprint in these ecosystems increases propagule pressure, helps habitat fragmentation, and facilitates adaptation of these invasive plants. Citizen science is as important as fundamental science and environmental management by public authorities to prevent new invasions. An in-depth analysis of the mechanistic processes underlying the evolution and ecophysiology of typical invasive plants such as Carpobrotus spp., Acacia spp., Agave spp., and Opuntia spp. in Mediterranean-type ecosystems shows very sophisticated, complex, and efficient strategies for invasion success, particularly in fragmented habitats. Propagule pressure at both geographical and temporal scales and the establishment of long-term seed banks are determinant for invasion success. A two-sword strategy based on long-term prevention and eradication is proposed for the management of Mediterranean-type ecosystems. Eradication of invasive plants in Mediterranean-type ecosystems appears to be extremely difficult nowadays and, at least for some invaders like Carpobrotus spp., long-term approaches that ultimately culminate in the elimination of seed banks is the only path for success. [ABSTRACT FROM AUTHOR]

Naturalisation risk and the vulnerability of many countries to future plant invasions is predicted to increase with human movement and climate change. Unfortunately, the geographical limitation on studies assessing unintentional human‐vectored dispersal (HVD) has hampered progress in understanding its importance, particularly its probability of introducing species that will become naturalised or invasive. The current paper used an explorative approach to determine if human clothing and vehicles disperse species with higher potential to become invasive globally. The study specifically relies on available database of unintentional human‐vectored seed dispersal and recent studies that considered the outcomes of plant species' interaction with humans around the world. The results indicate that human vehicles and clothing contribute to the spread of many extreme risk and most naturalised species of the world. For example, 55% of the 200 most naturalised species have been reported to be dispersed on vehicle while almost one ‐third (32%) have been reported to be dispersed on clothing. Also, of the 235 extreme risk species 41% have been reported to be dispersed on vehicles and 31% on clothing. The results indicate that graminoids, herbs and species with long‐term seed bank are more dispersed via HVD. Conservation managers and practitioners should consider the role of human‐vectored seed dispersal in the spread of invasive weeds, especially in popular and frequently visited areas. Individuals embracing responsible travel practices and adopting proactive measures and protocols to prevent the accidental transport of seeds can significantly enhance our conservation endeavours in our interconnected global ecosystem. [ABSTRACT FROM AUTHOR]

In response to non‐native plant invasions, many governments have established noxious weed lists to control and eradicate introduced invasive plants. However, invasive agronomic species are often unregulated, and the extent of their invasion across habitat types has never been determined. Using vegetation surveys across 222 plots, we investigated the contribution of agronomic versus noxious non‐native species to the levels of invasion across seven habitat types in central Canada. Although agronomic non‐native species, such as Poa pratensis and Bromus inermis, only made up 21.3% of the non‐native species pool, they accounted for 43.6% of non‐native plant species frequency and 74.4% of relative non‐native plant cover. They were also disproportionately overrepresented compared with noxious non‐native species across all habitat types, except saline marshes. The overabundance of agronomic non‐native plants in central Canada is likely the legacy of cultivar breeding, intentional seeding of introduced forage species and a lack of incentive for the use of native species. Synthesis and applications: Decelerating the invasion by agronomic non‐native plants will require approaches beyond noxious weed lists and initiatives in research, policy and education. These tools can include incentives to use native seed material, for example, in reclamation and forage and turf production, to reduce propagule pressure from invasive agronomic non‐native plants. [ABSTRACT FROM AUTHOR]

Although native species diversity is frequently reported to enhance invasion resistance, within‐species diversity of native plants can also moderate invasions. While the positive diversity–invasion resistance relationship is often attributed to competition, indirect effects mediated through plant–soil feedbacks can also influence the relationship. We manipulated the genotypic diversity of an endemic species, Scirpus mariqueter, and evaluated the effects of abiotic versus biotic feedbacks on the performance of a global invader, Spartina alterniflora. We found that invader performance on live soils decreased non‐additively with genotypic diversity of the native plant that trained the soils, but this reversed when soils were sterilized to eliminate feedbacks through soil biota. The influence of soil biota on the feedback was primarily associated with increased levels of microbial biomass and fungal diversity in soils trained by multiple‐genotype populations. Our findings highlight the importance of plant–soil feedbacks mediating the positive relationship between genotypic diversity and invasion resistance. [ABSTRACT FROM AUTHOR]

Non‐native‐dominated landscapes may arise from invasion by competitive plant species, disturbance and invasion of early‐colonizing species, or some combination of these. Without knowing site history, however, it is difficult to predict how native or non‐native communities will reassemble after disturbance events. Given increasing disturbance levels across anthropogenically impacted landscapes, predictive understanding of these patterns is important. We asked how disturbance affected community assembly in six invaded habitat types common in dryland, grazed landscapes on Island of Hawai'i. We mechanically disturbed 100 m2 plots in six vegetation types dominated by one of four invasive perennial grasses (Cenchrus ciliaris, Cenchrus clandestinus, Cenchrus setaceus, or Melinis repens), a native shrub (Dodonaea viscosa), or a native perennial bunchgrass (Eragrostis atropioides). We censused vegetation before disturbance and monitored woody plant colonization and herbaceous cover for 21 months following the disturbance, categorizing species as competitors, colonizers, or a combination, based on recovery patterns. In addition, we planted individuals of the native shrub and bunchgrass and monitored survival to overcome dispersal limitation of native species when exploring these patterns. We found that the dominant vegetation types showed variation in post‐disturbance syndrome, and that the variation in colonizer versus competitor syndrome occurred both between species, but also within species among different vegetation types. Although there were flushes of native shrub seedlings, these did not survive to 21 months within invaded habitats, probably due to regrowth by competitive invasive grasses. Similarly, survival of planted native individuals was related to the rate of regrowth by dominant species. Regardless of colonization/competitor syndrome, however, all dominant vegetation types were relatively resilient to change. Our results highlight that the altered post‐agricultural, invaded grassland landscapes in Hawaiʻi are stable states. More generally, they point to the importance of resident communities and their effects on species interactions and seed availability in shaping plant community response to disturbance. [ABSTRACT FROM AUTHOR]

Aims: Plant-soil feedback (PSF), which may vary across spaces and time, is considered as an important mechanism in biological invasions. However, it is still unclear how PSF changes during biological invasions in different environments. Methods: To address this problems, we measured aboveground biomass and cover of the invasive plant Ageratina adenophora, richness and diversity of its co-occurring natives, PSFs for the invader, soil nutrients and fungal communities at uninvaded, recently and long invaded sites in lightly and severely disturbed habitats. Results: Invasion time and habitats influenced PSFs for the invader interactively. As invasion time increased, the positive total PSFs (response to their soil biota relative to sterilized soil) shifted to neutral, and the negative specific PSFs (response to their own soil biota relative to other species' soil biota) became more stronger in lightly disturbed habitats, but not in severely disturbed habitats. The dominance of the invader and its ecological impacts remained similar in lightly disturbed habitats, while in severely disturbed habitats, both the invader's dominance and impacts increased. The dynamics of the PSFs were associated with soil nutrients and microbes, and the former may function indirectly via affecting the lattes. Soil pathogens and AMF contributed to the dynamics of the PSFs in some cases, but not in others. Conclusions: These findings indicate that the complex spatiotemporal dynamics of PSFs may contribute to the dynamics of dominance and impact of invasive species in forests, and highlight the need to consider the effects of invasion time and environments when studying PSFs. [ABSTRACT FROM AUTHOR]

Plant invasions driven by global environmental changes (e.g. nutrient enrichment) increasingly threaten natural ecosystems. It is unclear whether reducing nitrogen (N) inputs helps to mitigate plant invasions in natural ecosystems.Using ongoing, landscape‐scale N reductions in the Yangtze River, we combined spatiotemporal surveys before and after reducing N inputs and manipulative experiments to explore how N reductions contributed to native community recovery in estuarine marshes degraded by plant invasions.We found that native Phragmites australis patches gradually recovered in Spartina alterniflora‐invaded marshes after reducing N inputs. The competitive advantage of S. alterniflora over P. australis decreased with N reduction, shifting the competitive outcomes away from P. australis exclusion to their coexistence.Synthesis and applications. Our findings reveal that the reversal of nitrogen enrichment may shift ecosystems from being more susceptible to invasion toward successional recovery, offering a promising approach for facilitating native community recovery in the invaded ecosystems. These findings have important implications for restoring invaded ecosystems, especially as global environmental change escalates the extent and impact of invaders by exacerbating current invasions and facilitating new ones. [ABSTRACT FROM AUTHOR]

The Anthropocene witnessed the landscape spread of several invasive alien plants which can remarkably influence the ecosystem services and environmental sustainability. To this end, Chromolaena odorata (Asteraceae) is widely identified among top hundred pervasive invaders in view of its adverse influence on environment, agriculture, and wildlife. The adverse effects of C. odorata can further be exacerbated under the event of invasion interaction with other anthropogenic stressors such as climate change. Nevertheless, there exists dearth of pragmatic studies on invasion ecology, socio‐economic impacts, ecological economics, and sustainable management prospects of C. odorata. The present review discusses the invasion ecology, distribution, mechanisms, impacts, and management strategies of C. odorata invasion. The side‐effects and unsustainable use of traditional control measures (e.g., controlled fire and chemical herbicides) of C. odorata paves the way to biological control methods (e.g., gall fly). However, the control measures of C. odorata need to be assessed for their long‐term ecosystem level effects to mitigate the possible adverse environmental responses. The wise application of C. odorata biomass in marginal lands for soil fertility restoration, biosorption, biorefinery, bio‐medicine, and bioenergy in conjunction with ecological control measures can cover economic incentive to facilitate sustainable management of C. odorata in forestry/agroforestry systems. Nevertheless, the use of weed biomass as feedstock in biorefinery and ethno‐medicine may be inadequate in reducing its invasion. Future studies should explicitly elucidate the ecological mechanisms of C. odorata in concert with the quest for its field‐scale application in biorefinery to augment sustainable management. [ABSTRACT FROM AUTHOR]

• Myrtus communis is an invasive plant, particularly in South Africa. • Seed are killed by fire but plants persist through resprouting. • Fire interval, elevated atmospheric CO 2 , and successful genetic adaptation likely explain its success. • We consider M. communis to be a Category-E invasive under increased CO2 levels. • We recommend early detection and a swift response to outbreaks and the exploration of effective control treatments. A survey of recovering fynbos vegetation on the Cape Peninsula, Western Cape, South Africa, after a wildfire in April 2021, led to the discovery of a large naturalised population of the shrub Myrtus communis. This species, native to the Mediterranean Basin and Western Asia, is commonly used as an ornamental plant in many parts of the world, including Australia, Europe, New Zealand, South Africa and the United States. It is not recognized in major world invasive databases as being a problematic invasive species. We documented the recovery of this naturalised population and evaluated other records of naturalised occurrences in the Cape Town metropolitan area. We assessed the known characteristics of the species in terms of its fire tolerance, water relations, shade preference, seed set, dispersal and germination. We propose that fire constitutes a useful tool to expose this species for eradication through herbicide application. We argue that there is a limited window-period for eradication of this species locally before it spreads further and potentially exerts impacts on ecosystems. [ABSTRACT FROM AUTHOR]

The comparison of ecological, phenological, morphological and developmental traits between exotic invasive species and coexisting native species contributes to understand the driving mechanisms of successful invasions. This study aimed to examine which of these traits are related to the invasion of woody plants in the understory of deciduous North Patagonian forests of Argentina.We compared the phenology, shoot growth rate, number of leaves, biomass allocation, leaf herbivory, and recruitment type of two exotic deciduous trees, Crataegus monogyna and Sorbus aucuparia, with those of four coexisting native woody species (one deciduous, one semi‐deciduous, and two evergreen species).Spring shoot growth took place several weeks earlier in both exotic species and in the deciduous native species than in the other native species; growth rates were higher in the exotics. Compared to coexisting native species, both exotic species developed shoots that were as long as or longer, had lower biomass allocation to leaves and higher allocation to roots, suffered lower leaf damage by herbivores and exhibited higher seed than vegetative recruitment.This study supports the idea that a combination of phenological, growth rate and mass allocation traits allow exotic species to preempt resources, thus favouring invasion processes. [ABSTRACT FROM AUTHOR]

Abstract Background Globally, the structure and functioning of foreshore and riparian ecosystems are being dramatically impacted by non-native invasive plant species. Invasive species can outcompete and replace native species, modify geochemical and hydraulic cycles, alter trophic processes, and change the composition and structure of communities above and below ground. However, these impacts are often investigated in isolation, even though one invasive species might increase or mitigate the impacts of others (i.e. cumulative impacts), potentially with cascading effects. Although cumulative impacts have long been studied within other environmental contexts, research on the cumulative impacts of invasive species is comparatively scarce. We aim to develop a protocol to systematically identify and collate evidence on the individual and cumulative impacts of a set of plant species invasive in foreshore and riparian ecosystems of British Columbia, Canada. Our primary question is: what evidence is available on the individual and cumulative impacts of invasive plants in the riparian and foreshore ecosystems of British Columbia, Canada? In addition, our systematic map will identify the strengths and gaps in knowledge pertaining to invasive plant species impacts in foreshore and riparian ecosystems, with the ultimate goal of facilitating the development of evidence-based management strategies. Methods We identified the research topic and the primary and secondary questions with the support of stakeholders. We then devised a flexible string that allows for searching target invasive species. Using this string, we searched the literature for pilot species that aided the iterative development of the protocol. Once all target species are identified, we will carry out a systematic literature search on their impacts. We will search Web of Science and the CABI compendium for invasive species. We will include studies if they (i) refer to the target invasive species, (ii) focus on its environmental impacts and (iii) investigate such impacts in riparian ecosystems (iv) within North America (i.e. Canada and U.S.A.). We will use a two-stage screening process: titles and abstracts first, then the full manuscript. From each source, we will extract impact description, ecosystem component impacted, and magnitude and directionality of impacts. We will include a publicly available database of studies, descriptive statistics, and a narrative summary within our synthesis outcomes.

Alien species are colonizing mountain ecosystems and increasing their elevation ranges in response to ongoing climate change and anthropogenic disturbances, posing increasing threats to native species. However, how quickly alien species spread upward and what drives their invasion remains insufficiently understood. Here, using 26,952 occurrence records of 58 alien plant species collected over two centuries in the Czech Republic, we explored the elevation range and invasion speed of each alien species and the underlying factors driving these variables. We collected species traits relevant for invasion (e.g., clonality, flowering time, life span, invasion status, height, mycorrhizal type, native range, naturalized range, monoploid genome size, and Ellenberg-type indicator values for light, temperature, and nitrogen), human-associated factors (e.g., introduction pathways and the sum of economic use types), and minimum residence time. We explored the relationships between these factors and species' elevation range and invasion speed using phylogenetic regressions. Our results showed that 58 alien species have been expanding upward along mountain elevations in the Czech Republic over the past two centuries. A stronger effect of species' traits than human-associated factors has been revealed, e.g., clonality was a key trait supporting the invasion of alien species into the mountains, while human-associated factors showed no effect. Our findings highlight that the characteristics associated with rapid reproduction and spread are crucial for alien species' invasion into montane regions. Identifying key drivers of this process is important for predicting the spatiotemporal dynamics of alien species in high-altitude ecosystems and thus employing apposite measures to reduce the threat to native plant species. [ABSTRACT FROM AUTHOR]

Plant invasions can have major impacts on ecosystems, both above‐ and belowground. In particular, invasions by legumes, which often host nitrogen‐fixing symbionts (rhizobia), are known to modify soil bacterial communities. Here, we examined the effect of the invasive herbaceous legume Lupinus polyphyllus on the alpha diversity and community composition of soil bacteria. We also explored the relationships between these bacterial communities and vegetation cover, the cover of other (non‐invasive) legumes, or the number of vascular plants present. For this, we sampled rhizosphere soil and surveyed vegetation from ten paired sites (uninvaded versus invaded more than 10 years ago) in southwestern Finland, and identified bacterial DNA using 16S rRNA gene amplicon sequencing. The presence of the plant invader and the three vegetation variables considered had no effect on the alpha diversity of soil bacteria in terms of bacterial richness or Shannon and Inverse Simpson diversity indices. However, the composition of soil bacterial communities differed between invaded and uninvaded soils at four out of the ten sites. Interestingly, the relative abundances of the top bacterial families in invaded and uninvaded soils were inconsistent across sites, including for legume‐associated rhizobia in the family Bradyrhizobiaceae. Other factors—such as vegetation cover, legume cover (excluding L. polyphyllus), number of plant species—also explained a small proportion of the variation in bacterial community composition. Our findings indicate that L. polyphyllus has the potential to modify the composition of local soil bacterial community, at least in sites where it has been present for more than a decade. [ABSTRACT FROM AUTHOR]

The tropical seagrass Halophila stipulacea invaded the Eastern Mediterranean Sea in the late nineteenth century and progressively spread throughout the basin ever since. Its spread is expected to continue north-westward as the Mediterranean Sea becomes warmer, potentially changing the seagrass biogeography of the basin. Given the power of genomics to assess invasion dynamics in non-model species, we report the first ddRAD-seq study of H. stipulacea and small-scale population genomic analysis addressing its century-old Mediterranean invasion. Based on 868 SNPs and 35 genotyped native (Red Sea) and exotic (from Cyprus, Greece, and Italy) samples, results suggest that genetic structure was high, especially between major geographic discontinuities, and that exotic populations maintain comparably lower genetic diversity than native populations, despite 130 years of invasion. The evidence of high heterozygosity excess, coupled with previously reported male-dominated and rare flowering records in the exotic range, suggests that clonal propagation likely played a pivotal role in the successful colonization and spread of H. stipulacea in the Mediterranean. This shift in reproductive strategy, particularly evident in the Italian populations located closest to the western boundary and representing more recent establishments, underscores the importance of this cost-effective mode of reproduction, especially during the initial stages of invasion, raising questions about the species future expansion trajectory. Our findings serve as a catalyst for future research into the species' invasion dynamics, including deciphering the intricate roles of acclimatization and rapid adaptation, important for a comprehensive assessment of invasion risks and improving management strategies aimed at conserving seagrass ecosystems. [ABSTRACT FROM AUTHOR]

Invasive species pose significant challenges to successful restoration efforts worldwide. A strategy to reduce invasions is to establish communities consisting of species with varied ecological strategies. These strategies typically align along the conservative and plant size axes, and more recently, along a below‐ground collaboration axis. However, we lack understanding of how the diverse ecological strategies of Cerrado grass species, their combinations and their interactions with soil conditions can mitigate invasions.Here, we investigated how native grass communities composed by species with different ecological strategies affect the invasion success in two soil types of abandoned pastures in the Cerrado. Specifically, we tested the hypothesis that greater above‐ and below‐ground functional diversity reduces exotic species invasion. We also evaluated whether the isolated effects of native species on invasion were positive or negative.We installed an experiment with species richness ranging from zero to eight native grass species. In November 2019, we sowed species combinations to create communities composed by species with different ecological strategies. We quantified the above‐ground biomass of exotic species as a measure of invasion. To characterize the species ecological strategies, we measured five functional traits.Functional diversity of maximum height and specific root length (SRL) had the highest predictive power; however, the most parsimonious model included only SRL diversity, which represents the collaboration axis. Native above‐ground biomass was also negatively related to exotic species biomass. Furthermore, invasion was greater in less stressful soil conditions but did not interact with diversity. The effect of native species varied from facilitation to competition, with the annual fast‐growing native species favouring invasion.Synthesis and applications. Our results show that greater functional diversity of combined above‐ and below‐ground traits reduces invasion success, shedding light on an underexplored role of specific root length diversity. The competitive and facilitative effects of different native species highlight the need for careful selection of the species to be used in restoration programmes. Furthermore, the absence of interaction between diversity and soil types highlights the need for an integrated management of the functional composition and edaphic factors to increase resistance to invasion in these Neotropical grass communities. [ABSTRACT FROM AUTHOR]

Insights into ecological drivers of alien plant invasions can be gained through comparative studies of growth and fecundity of invasive alien plants versus those of co‐occurring non‐invasive alien plants and native plants across environmental conditions in common garden settings. Habitats that harbour alien plant species in many ecosystems globally are presently experiencing light pollution resulting from artificial light at night (ALAN) and increased rates of nutrient enrichment of the soil. However, the potential interactive effects of ALAN and nutrient enrichment on invasiveness of alien plant species remain unknown.Here, we performed a common‐garden experiment to test the interactive effects of ALAN and soil nutrient enrichment on the growth of a random set of ten alien (five invasive and five non‐invasive naturalized) and seven co‐occurring native ornamental plant species that are commonly cultivated within urban and peri‐urban areas of Nairobi city in Kenya. We predicted that a simultaneous increase in photoperiod via ALAN and nutrient enrichment will favour growth of invasive alien plant species over that of non‐invasive alien and native plant species. We grew the 17 plant species under natural daylight (ALAN−) versus natural daylight followed by ALAN (ALAN+) and fully crossed with two levels of nutrient enrichment (low vs. high) and competition (competition vs. no‐competition against a native plant Ocimum gratissimum) treatments.Under simultaneous high‐nutrient and no‐competition treatments, ALAN enhanced mean total biomass of invasive and non‐invasive naturalized alien species by 61.1% and 131.4%, respectively but decreased that of native plant species by 34%. In contrast, under simultaneous high‐nutrient and competition treatments, ALAN enhanced mean total biomass of invasive alien plant species by 68.6% and that of non‐invasive naturalized alien species by 51.9% and native species by 35.4%. High‐nutrient treatment enhanced flower formation more strongly in invasive and non‐invasive naturalized alien plants than in native plants. The invasive and non‐invasive naturalized alien species grew taller than native species across the light, nutrient, and competition treatments.Synthesis: The present findings suggest that light pollution and nutrient enrichment may jointly confer growth advantage to invasive alien plant species over that of co‐occurring native plant species and enhance invasiveness of alien plant species. [ABSTRACT FROM AUTHOR]

Biological invasions threaten global biodiversity and can have severe economic and social impacts. The complexity of this problem challenges effective management of invasive alien species as the contribution of many factors involved in the invasion processes across different spatial scales is not well understood.Here, we identify the most important determinants associated with the occurrence of two invasive alien plants, the North American goldenrods (Solidago canadensis and S. gigantea), commonly found in agricultural landscapes of Europe. We used Google Street View images to perform a remote, large‐scale inventory of goldenrods along 1347 roadside transects across Poland. Using open access geospatial data and machine learning techniques, we investigated the relative role of nearly 50 variables potentially affecting the distribution of studied species at five spatial scales (from within 0.25 to 5 km of the studied locations).We found that the occurrence of goldenrods along roadsides was simultaneously associated with multiple drivers among which those related to human impacts, climate, soil properties and landscape structure were the most important, while local characteristics, such as road parameters or the presence of other alien plants were less influential. However, the relative contribution of different variables in predicting goldenrod distribution changed across spatial scales.Synthesis: Mechanisms underlying plant invasions are highly complex and a number of factors can jointly influence the outcomes of this process. However, since different invasion drivers operate at different spatial scales, some important associations may be overlooked when focusing on a single spatial context. Although associations were consistent in direction (positive or negative) across scales, their relative influence on goldenrod occurrence often changed. Socio‐economic factors were largely important at local scales, while the effect of landscape factors broadly increased with increasing spatial scale. We highlight that using multi‐scale approaches involving a wide range of variables may enable setting priorities for the management of invasive alien plants. [ABSTRACT FROM AUTHOR]

Species invasions can disrupt aquatic ecosystems by re‐wiring food webs. A trophic cascade triggered by the invasion of the predatory zooplankter spiny water flea (Bythotrephes cederströmii) resulted in increased phytoplankton due to decreased zooplankton grazing. Here, we show that increased phytoplankton biomass led to an increase in lake anoxia. The temporal and spatial extent of anoxia experienced a step change increase coincident with the invasion, and anoxic factor increased by 11 d. Post‐invasion, anoxia established more quickly following spring stratification, driven by an increase in phytoplankton biomass. A shift in spring phytoplankton phenology encompassed both abundance and community composition. Diatoms (Bacillaryophyta) drove the increase in spring phytoplankton biomass, but not all phytoplankton community members increased, shifting the community composition. We infer that increased phytoplankton biomass increased labile organic matter and drove hypolimnetic oxygen consumption. These results demonstrate how a species invasion can shift lake phenology and biogeochemistry. [ABSTRACT FROM AUTHOR]

The Argentine ant, Linepithema humile, is one of the world's worst invasive species, with established populations in at least 40 countries on six continents. In this review, we synthesise the vast literature on this species in four areas, concentrating on its introduction to natural systems. The first section reviews its distribution, habitat preferences, and the factors promoting its invasion success. Second, we review current knowledge of its ecological impacts on invertebrates, vertebrates and ecosystem functions. The third section deals with behaviour and genetics, particularly traits promoting invasiveness. Finally, we address applied issues, emphasising the quantification of the economic costs and eradication strategies associated with L. humile invasion. Despite tremendous research efforts, especially over the past 40 years, numerous knowledge gaps remain in the understanding of the distribution, ecology, impacts, management, and economic costs of this species. We conclude by highlighting the most critical gaps and propose a research agenda to tackle the future challenges in the study of L. humile biology. [ABSTRACT FROM AUTHOR]

Questions: Oceanic islands are global hotspots of endemism and evolutionary radiations but many have been severely degraded by human activities and biological invasions. We evaluated the pace and direction of the natural recovery of ecosystems over 77 years across a subtropical oceanic archipelago including islands of various size, elevation, histories of human settlement and deforestation, and invasions by non‐native plants and mammals. This information is essential to guide the ecological restoration of the archipelago. Location: Forest vegetation on nine of the Ogasawara Islands in the northwestern Pacific Ocean. Methods: We first digitized historical vegetation data of the Ogasawara Islands collected during field surveys in 1935. Then, after checking their species compositions, we integrated past and present plant community types. Finally, we identified the landscape‐scale changes in forest vegetation by comparing vegetation maps from 1935, 1979 and 2012. Results: Over 77 years, the vegetation trajectories of each island varied depending on the introduction of invasive alien species and the remaining proportion of native forest, the latter of which had a strong influence on the recoverability of native forest. Conclusions: Our results highlight the importance of the history of invasive species introductions and the remaining proportion of native forest—both of which reflect the intensity of anthropogenic disturbance—in determining the degree of human intervention needed for restoration on oceanic islands. [ABSTRACT FROM AUTHOR]

To compare the capacity of native and exotic vine species established under a rainforest canopy, a comparison of growth rates and resource allocation was made amongst five exotic vine species that are serious and common invaders and two common native vine species under two light conditions reflective of edge and interior canopy conditions. All species experienced heavy reductions in growth parameters in the lowlight treatment, but three exotic species showed stronger growth under the low light. All exotic species had higher plasticity in leaf morphology showing a significant increase in SLA under low light. Native vines may have a lower capacity to change leaf morphology in shade, as a result of local adaptation to edge habitats. Higher SLA under both low and high light conditions suggests that exotic vines species are able to exploit a range of forest conditions better than the native species. Three species, Anredera cordifolia, Araujia sericifera and Cardiospermum grandiflorum, appear particularly capable of invading rainforest interiors. Individuals produced few leaves, focusing resources on roots and stems suggesting a response to reach the canopy quickly. With their long-distance seed dispersal, plasticity in leaf SLA and high RGR, these species appear most likely to invade undisturbed rainforest. [ABSTRACT FROM AUTHOR]

Experiments often find that net primary productivity (NPP) increases with species richness when native species are considered. However, relationships may be altered by exotic (non‐native) species, which are hypothesized to reduce richness but increase productivity (i.e., 'invasion‐diversity‐productivity paradox'). We compared richness‐NPP relationships using a comparison of exotic versus native‐dominated sites across the central USA, and two experiments under common environments. Aboveground NPP was measured using peak biomass clipping in all three studies, and belowground NPP was measured in one study with root ingrowth cores using root‐free soil. In all studies, there was a significantly positive relationship between NPP and richness across native species‐dominated sites and plots, but no relationship across exotic‐dominated ones. These results indicate that relationships between NPP and richness depend on whether native or exotic species are dominant, and that exotic species are 'breaking the rules', altering richness‐productivity and richness‐C stock relationships after invasion. [ABSTRACT FROM AUTHOR]

Species invasions are predicted to increase in frequency with global change, but quantitative predictions of how environmental filters and species traits influence the success and consequences of invasions for local communities are lacking. Here we investigate how invaders alter the structure, diversity and stability regime of simple communities across environmental gradients (habitat productivity, temperature) and community size structure. We simulate all three‐species trophic modules (apparent and exploitative competition, trophic chain and intraguild predation). We predict that invasions most often succeed in warm and productive habitats and that successful invaders include smaller competitors, intraguild predators and comparatively small top predators. This suggests that species invasions and global change may facilitate the downsizing of food webs. Furthermore, we show that successful invasions leading to species substitutions rarely alter system stability, while invasions leading to increased diversity can destabilize or stabilize community dynamics depending on the environmental conditions and invader's trophic position. [ABSTRACT FROM AUTHOR]

The invasion of alien plant species threatens the composition and diversity of native communities. However, the invasiveness of alien plants and the resilience of native communities are dependent on the interactions between biotic and abiotic factors, such as natural enemies and nutrient availability. In our study, we simulated the invasion of nine invasive plant species into native plant communities using two levels of nutrient availability and suppression of natural enemies. We evaluated the effect of biotic and abiotic factors on the response of alien target species and the resistance of native communities to invasion. The results showed that the presence of enemies (enemy release) increased the biomass proportion of alien plants while decreasing that of native communities in the absence of nutrient addition. Furthermore, we also found that the negative effect of enemy suppression on the evenness of the native community and the root‐to‐shoot ratio of alien target species was greatest under nutrient addition. Therefore, nutrient‐poor and natural enemies might promote the invasive success of alien species in native communities, whereas nutrient addition and enemy suppression can better enhance the resistance of native plant communities to invasion. [ABSTRACT FROM AUTHOR]

Simple Summary: The effects of invasive plants on species diversity and ecosystem stability differ owing to the different stages of invasion. Xanthium spinosum is an invasive weed that is widely distributed in Europe, Asia, and North America. Its adaptability and competitive advantage over native species have led to agricultural loss and biodiversity reduction, yet its impact on local plant communities under different degrees of invasion has not been reported. Therefore, in this study, we aimed to investigate the effects of different degrees of invasion by X. spinosum on the diversity, stability, and invasibility of local plant communities in Yining County, Xinjiang, China. We believe that our study makes a significant contribution to the literature because we found that as the degree of X. spinosum invasion increased, species diversity and community stability decreased, while community invasibility increased. Notably, a light degree of invasion was found to enhance the diversity and stability of local plant communities. Based on our findings, we recommend that X. spinosum be controlled and eradicated in the early stages of invasion to prevent further invasion and harm to indigenous species. Studying the effects of different degrees of exotic plant invasion on native plants' community structure and plant diversity is essential for evaluating the harm caused to ecosystems by plant invasion. In this study, we investigated the effects of Xanthium spinosum, a widespread invasive species, on plant community species diversity and community stability in the Ili River Valley area of Xinjiang, China, under three invasion levels (no invasion and low, moderate, and heavy invasion), and the competitive advantage index, invasion intensity, and contribution of plant community species diversity to community stability and invasibility were determined for the prickly fungus under different degrees of invasion. The results show that there were significant differences (p < 0.05) in the species diversity and community stability of plant communities caused by different degrees of invasion of X. spinosum. The species diversity and stability of plant communities were negatively correlated with the community invasibility, competitive advantage, and invasion intensity of X. spinosum (p < 0.05); therefore, the competitive advantage and invasion intensity of X. spinosum increase with the increase of its invasion degree. On the contrary, community species diversity and stability decreased with the increase of its invasion degree, ultimately leading to differences in community invasibility under different invasion degrees. The Shannon–Wiener and Simpson's indices were the greatest contributors to community stability and invasibility, respectively. Moderate and heavy levels of invasion by X. spinosum reduced the diversity and stability of local plant communities, increased the invasibility of communities, and substantially affected the structures of plant communities. Therefore, the continued invasion by X. spinosum will have an immeasurable impact on the fragile ecosystems and diversity of indigenous species in Xinjiang. We recommend that this invasive species be controlled and eradicated at the early stages of invasion to prevent further harm. [ABSTRACT FROM AUTHOR]

This paper reviews and discusses the main features of biological invasion by plants and the assisted migration theory referencing a critical common factor—belowground ecology. The risk of a plant becoming invasive and the potential failure of assisted migration programs depend on the presence or absence of soil microorganisms that regulate key ecosystem processes and mitigate adverse environmental conditions. This biotic interaction should be considered in the selection of sites for afforestation programs since it is as important as temperature and precipitation regarding conservation decisions, and assisted migration practices in response to climate change. Fungal species should be determined and included in climate change mitigation programs to avoid disease outbreaks and ensure the presence of beneficial mutualistic species in sites selected for assisted migration. Plants considered for assisted migration should pose a low risk of becoming invasive for having establishment difficulties per se. However, the real threat is that they may displace other species, introduce pathogens, or trigger disease outbreaks in introduction sites that nullify assisted migration efforts. [ABSTRACT FROM AUTHOR]

Introduced alien species are associated with lower taxonomic, functional and phylogenetic diversity of native communities and negative impacts on ecosystem functioning. This is particularly evident in habitats where human disturbance may favour alien species, posing an additional stressor on native communities. Following the community resistance hypothesis (higher diversity promotes higher resistance to invasion), we predicted: 1) higher taxonomic, functional and phylogenetic diversity (TD, FD and PD respectively) in non‐invaded bird communities (i.e. no alien bird species); and 2) higher diversity and resistance to invasion in less human‐disturbed areas. We surveyed bird communities in a modified Mediterranean landscape subject to varying levels of human disturbance. We tested whether TD, FD and PD were significantly different between non‐invaded and invaded bird communities, and assessed the effect of land classes (forest, agriculture, urban), landscape composition and heterogeneity on these metrics. We found that non‐invaded communities retained higher TD and FD, but not PD, than invaded communities. Alien birds occupied marginal niches in invaded communities, and did not fully compensate for the taxonomic and functional diversity loss caused by the absence of native species. These results were consistent across different land classes, suggesting weak environmental filtering of communities. Generally, less human‐modified and more heterogeneous areas supported higher TD regardless of the presence of alien species. FD and PD of invaded communities decreased with increases in human‐modified areas, whereas non‐invaded communities were not affected. Our results suggest that even within a human‐modified landscape, invaded community diversity is more affected by, and thus has a lower resilience to, disturbance. Restoring and protecting natural habitats within human‐modified landscapes is likely to increase the resilience of native species. [ABSTRACT FROM AUTHOR]

Climate change is increasing the frequency and intensity of extreme events like drought and flooding, which threaten to amplify other global change drivers such as species invasion. We investigate the effect of wet and dry extreme precipitation regimes on invasive species' abundances in northern tallgrass prairies. Because soil moisture is a key determinant of prairie composition, theory and evidence suggest drought conditions will hinder invasion, whereas wetter conditions will enhance invasion. To test this hypothesis, we explored the effect of precipitation on invasive plant species abundance from 2010 to 2019 in 25 managed prairies using observations from 267 transects comprising 6675 plots throughout western Minnesota, USA. We estimated how increases in the number of extremely wet or dry months in a year altered overall invasive species abundance and the abundance of the highly invasive grasses Poa pratensis and Bromus inermis. We found that a greater occurrence of abnormally wet months increased invasive species abundance but found mixed evidence that abnormally dry conditions hindered invasion. Further, more moderately wet and dry months reduced native grass abundance. Together, these results suggest that more frequent extremely wet months may intensify invasive dominance and that dry months may not counterbalance these trends. Given the considerable uncertainty still surrounding the interactive effects of climate change and invasion on native plant communities, this research represents an important step toward quantifying the complex influence of precipitation extremes on invasion dynamics in managed ecosystems of critical conservation concern. [ABSTRACT FROM AUTHOR]

Aim: Preventing the spread of range‐shifting invasive species is a top priority for mitigating the impacts of climate change. Invasive plants become abundant and cause negative impacts in only a fraction of their introduced ranges, yet projections of invasion risk are almost exclusively derived from models built using all non‐native occurrences and neglect abundance information. Location: Eastern USA. Methods: We compiled abundance records for 144 invasive plant species from five major growth forms. We fit over 600 species distribution models based on occurrences of abundant plant populations, thus projecting which areas in the eastern United States (U.S.) will be most susceptible to invasion under current and +2°C climate change. Results: We identified current invasive plant hotspots in the Great Lakes region, mid‐Atlantic region, and along the northeast coast of Florida and Georgia, each climatically suitable for abundant populations of over 30 invasive plant species. Under a +2°C climate change scenario, hotspots will shift an average of 213 km, predominantly towards the northeast U.S., where some areas are projected to become suitable for up to 21 new invasive plant species. Range shifting species could exacerbate impacts of up to 40 invasive species projected to sustain populations within existing hotspots. On the other hand, within the eastern U.S., 62% of species will experience decreased suitability for abundant populations with climate change. This trend is consistent across five plant growth forms. Main Conclusions: We produced species range maps and state‐specific watch lists from these analyses, which can inform proactive regulation, monitoring, and management of invasive plants most likely to cause future ecological impacts. Additionally, areas we identify as becoming less suitable for abundant populations could be prioritized for restoration of climate‐adapted native species. This research provides a first comprehensive assessment of risk from abundant plant invasions across the eastern U.S. [ABSTRACT FROM AUTHOR]

Aim Location Taxon Methods Results Main conclusions New areas are often simultaneously invaded by closely related alien species; however, between‐species differences in the course of their invasive spreading due to diverse ecological preferences have rarely been investigated. Here, we aim to study the species‐specific spatio‐temporal invasion patterns of Solidago canadensis and S. gigantea.Slovakia—the Western Carpathian and adjacent Pannonian regions.Invasive alien Solidago canadensis and S. gigantea.Our study was based on revised herbarium specimens, a recent field survey which included gathering abundance and habitat data, and environmental data from GIS layers. We characterised the environmental niche differentiation between S. canadensis and S. gigantea. Generalised additive models were then used to identify the key drivers of the species' occurrences and to assess their potential current and future distributions.Both species began to spread in Slovakia in the 1850s; in the first 100 years, the number of S. gigantea sites increased exponentially, while that of S. canadensis remained low. Currently, S. canadensis is more widespread in the region. The species have similar habitat preferences. Their environmental niches overlap, but are not identical. The core distribution of S. canadensis is in foothills and valleys that experience lower annual mean temperatures, while that of S. gigantea is in lowlands with higher annual mean temperatures. A large part of their potential distribution areas seems to be already invaded. Possible future climate change could stimulate the spreading of S. canadensis into higher altitudes and S. gigantea farther into lowlands and Carpathian foothills.The studied invasive Solidago species differed considerably in the early stages of invasion. Their environmental niches, current realised and potential distribution patterns are different. In the studied region, further spreading, with an increase in the number and size of populations, is likely unless effective measures are undertaken. [ABSTRACT FROM AUTHOR]

The mechanisms of species dispersal and colonization that drive the process of range expansion have always been in the focus of fundamental ecology. Typically, species' ranges change slowly, but human activities through global processes (landscape transformations, climate warming, and biological invasions) have sped up changes in species distributions, thus providing opportunities to observe and study range shifts in real time. In Kalmykia, human-induced landscape transformations from desert to steppe and vice versa allowed us to study the colonization process during range expansion in a desert-dwelling rodent, the midday gerbil (Meriones meridianus). We studied the population dynamics and changes in the range of midday gerbils in the southern part of Kalmykia, their physical conditions, and infestation with fleas on the wave of colonization, as well as demographic properties of the population of colonists compared to the source population. We found that, in recent years, the species range has been rapidly expanding to the west, where gerbils have established new colonies. The colonists differed significantly from the residents of the source population in a lower average body weight, this being associated not with the poorer physical conditions but with the age structure: the fertility rates of female colonists were much higher, and the population of colonists was much younger compared to the source population. In addition, colonists were almost not infested by fleas in contrast to the residents of the source population. Our findings indicate that the population on the wave of colonization does not experience the negative effects of low numbers, and the high reproductive rates in the colonist population account for its rapid growth and expansion. [ABSTRACT FROM AUTHOR]

Invasive species can cause drastic changes to plant communities. In many cases, removal of invasive species fails to reverse these changes, perhaps due to side effects of removal strategies, changes that co-occurred with invasion, or legacy effects. Carpobrotus edulis is a notorious invasive species in Mediterranean-type climates around the world that alters plant communities and may generate legacy effects. We investigate the impact of C. edulis invasion, removal, and potential legacy effects on coastal plant communities. We assessed community composition, species richness, diversity, and native and exotic species cover at 5 sites differing in C. edulis invasion and removal history. Community composition differed at all sites; however, the uninvaded and oldest removal sites were most similar, indicating that the previous C. edulis invasion did not influence longer-term community trajectory. Species richness and diversity were lowest at the invaded and recent removal sites but recovered to higher levels similar to the uninvaded site at the middle and oldest removal sites. Native cover was higher at removal sites than at the invaded site. Exotic species cover was highest at the invaded site but was not statistically significantly different between the invaded, oldest removal, and uninvaded sites. However, the invaded site was dominated by C. edulis, while the other sites were dominated by exotic grasses. These results suggest that C. edulis invasion reduces species richness and diversity while it is present and for a short time after it is removed, but that these effects are transient dynamics that likely do not generate soil legacy effects that alter community trajectory. However, at sites where C. edulis is absent or removed, other invasive species may dominate. [ABSTRACT FROM AUTHOR]

Invasive alien plant species (IAPS) frequently offer both ecosystem services and disservices to rural communities with high livelihood dependency on local landscapes. However, biocultural relationships with IAPS may go deeper than just provisioning uses, as they may be assimilated into local belief systems manifest in them becoming embedded in cultural constructions such as naming, stories, songs and ceremonies. It is likely that IAPS that are culturally assimilated will represent a greater conflict of interest in the face of proposed controls of IAPS in biodiversity hotspots where conservation priorities are frequently deemed paramount by external agencies. Using a mixed-methods approach we undertook roadside surveys of 17 selected IAPS along the 250 km Wild Coast section of the Maputaland-Pondoland-Albany biodiversity hotspot, accompanied by questionnaire interviews with 48 local people. The mean number of IAPS per site was four, ranging from zero (only one site) to ten, and local inhabitants deemed the abundance of all but one of the species to be increasing. All species had been in the region for decades, had a vernacular name, and all but one had direct consumptive uses. Species with multiple uses were more widely recognised. However, there was only marginal incorporation of the IAPS into stories, songs and ceremonies, although medicinal uses of some IAPS were for cultural/spiritual needs rather than physical ailments per se. These results show that despite widespread use, there was as yet relatively limited cultural assimilation of the IAPS in the Wild Coast region. [ABSTRACT FROM AUTHOR]

• Unsuitable agricultural practices in Lesotho have resulted in degradation of its rangelands, which in turn has given rise to pervasive plant invasion. • Rosa rubiginosa invasion negatively affects abundance of herbaceous vegetation, rangeland quality and subsequent livestock production. • Rosa rubiginosa affects soil properties by increasing pH and affecting nutrient concentration. The capacity of many rangelands in Lesotho is compromised due to plant invasion, resulting from unsuitable agricultural practices. Despite a high number and abundance of invasive plants in Lesotho, there are very few studies determining the invasion ecology to inform management interventions. Rosa rubiginosa L. is one of the most common invasive species invading the rangelands of Lesotho and has notable negative ecological impacts. The aim of this study was to assess rangeland condition following the invasion by Rosa rubiginosa and determine the ecological impacts thereof. This was achieved by assessing the herbaceous species cover and abundance, as well as edaphic factors following R. rubiginosa invasion. The results show that R. rubiginosa negatively affects rangelands by reducing the abundance of herbaceous species, including palatable grass species. In addition, it is shown that the plant alters soil conditions by increasing pH by 27% and affecting nutrient availability. This enhances growth of invasive species since they have competitive advantage in accessing available nutrients over native plants. It is therefore recommended that R. rubiginosa should be managed in the rangelands to improve rangeland productivity. [ABSTRACT FROM AUTHOR]

Since Baker's attempt to characterize the 'ideal weed' over 50 years ago, ecologists have sought to identify features of species that predict invasiveness. Several of Baker's 'ideal weed' traits are well studied, and we now understand that many traits can facilitate different components of the invasion process, such as dispersal traits promoting transport or selfing enabling establishment. However, the effects of traits on invasion are context dependent. The traits promoting invasion in one community or at one invasion stage may inhibit invasion of other communities or success at other invasion stages, and the benefits of any given trait may depend on the other traits possessed by the species. Furthermore, variation in traits among populations or species is the result of evolution. Accordingly, evolution both prior to and after invasion may determine invasion outcomes. Here, we review how our understanding of the ecology and evolution of traits in invasive plants has developed since Baker's original efforts, resulting from empirical studies and the emergence of new frameworks and ideas such as community assembly theory, functional ecology, and rapid adaptation. Looking forward, we consider how trait-based approaches might inform our understanding of less-explored aspects of invasion biology ranging from invasive species responses to climate change to coevolution of invaded communities. [ABSTRACT FROM AUTHOR]

Plant invasions can change native communities in complex ways. Restoring invasion-altered habitats starts with invader removal, and imposes significant physical and compositional changes. Restoration facilitates desirable plant community development, but arthropod community responses to removal and the timelines required for native vegetation establishment are difficult to predict. We examined initial effects of Elaeagnus angustifolia (Russian olive) removal on arthropod communities during a long-term experiment evaluating the combined consequences of invasive shrub removal and plant community restoration. We sampled E. angustifolia -invaded areas pre-removal (2010) and post-removal (2013) using sweep netting, and identified arthropods to family level. We found greater variation in the arthropod community composition within removal blocks than within invaded blocks after two years. These shifts resulted from changes in the relative abundance of community members (e.g. Dictynidae (Araneae), Culicidae (Diptera), and Cicadellidae (Hemiptera)), rather than overall richness or diversity. This response is likely due to increased plant diversity in E. angustifolia removal sites but also structural differences in vegetation cover after removal. Removing a dominant structural element like E. angustifolia instantly changes the successional stage of the ecosystem. Thus, restoration managers should consider methods that maintain structural continuity during restoration implementation. Arthropods provide important ecosystem services such as nutrient cycling and pollination and serve as a prey base for higher trophic levels. Thus, understanding how arthropod communities change after plant restoration events is vital to assessing future management decisions to limit ecosystem impacts of invasive plants and their management. [ABSTRACT FROM AUTHOR]

Large parts of the Earth are experiencing environmental change caused by alien plant invasions, rising atmospheric concentration of carbon dioxide (CO2), and nutrient enrichments. Elevated CO2 and nutrient concentrations can separately favour growth of invasive plants over that of natives but how herbivory may modulate the magnitude and direction of net responses by the two groups of plants to simultaneous CO2 and nutrient enrichments remains unknown. In line with the enemy release hypothesis, invasive plant species should reallocate metabolites from costly anti‐herbivore defences into greater growth following escape from intense herbivory in the native range. Therefore, invasive plants should have greater growth than native plants under simultaneous CO2 and nutrient enrichments in the absence of herbivory. To test this prediction, we grew nine congeneric pairs of invasive and native plant species that naturally co‐occurred in grasslands in China under two levels each of nutrient enrichment (low‐nutrient vs. high‐nutrient), herbivory (with herbivory vs. without herbivory) and under ambient (412.9 ± 0.6 ppm) and elevated (790.1 ± 6.2 ppm) levels of CO2 concentrations in open top chambers in a common garden. Elevated CO2 and nutrient enrichment separately increased total plant biomass, while herbivory reduced it regardless of the plant invasive status. High‐nutrient treatment caused the plants to allocate a significantly lower proportion of total biomass to roots, while herbivory induced an opposite pattern. Herbivory suppressed total biomass production more strongly in native plants than invasive plants. The plants exhibited significant interspecific and intergeneric variation in their responses to the various treatment combinations. Overall, these results suggest that elevated CO2 and nutrients and herbivory may separately, rather than synergistically, impact productivity of the invasive and co‐occurring native plant species in our study system. Moreover, interspecific variation in resource‐use strategies was more important than invasive status in determining plant responses to the various treatment combinations. [ABSTRACT FROM AUTHOR]

Urbanization results in rapid land transformations impacting bio-diversity and ecosystem services. With urban expansions population transition will predominantly occur in the peri-urban areas of the world's metropolitan cities like India, China, and Nigeria, which are often located in naturally species-rich regions and highly vulnerable to plant invasions. Thus it is increasingly important to monitor the changes occurring in the floral composition in such areas. The present study was therefore conducted across peri-urban habitats of Greater Kolkata, in order to establish a baseline data on plant species richness, invasive species co-occurrence, invader dominance and understand the bio-diversity pattern. Results showed a total of 62 plant species, mostly annual herbs, belonging to 29 families constituting the species richness in the study area. Both native (53%) and alien (47%) species were almost equally distributed and invasive species (32%) represented the majority among alien species. The findings also indicate that the species pool was dominated by sparsely distributed species. The number of invasive species varied from 2 to 9 per site, with 80% of sites supporting 3 or more species. Alternanthera philoxeroides and Mikania micrantha were the most frequently occurring invasive species. Overall, M. micrantha appeared to be the dominant species with 62% of sites with a high cover (> 70%) and was found to be evenly distributed in areas. However, they pose serious threat to local bio-diversity which shows that species-specific management is needed even in the peri-urban habitats. [ABSTRACT FROM AUTHOR]

Pre-adaptation to anthropogenic disturbance is broadly considered key for plant invasion success. Nevertheless, empirical evidence remains scarce and fragmentary, given the multifaceted nature of anthropogenic disturbance itself and the complexity of other evolutionary forces shaping the (epi)-genomes of recent native and invasive plant populations. Here, we review and critically revisit the existing theory and empirical evidence in the field of evolutionary ecology and highlight novel integrative research avenues that work at the interface with archaeology to solve open questions. The approaches suggested so far focus on contemporary plant populations, although their genomes have rapidly changed since their initial introduction in response to numerous selective and stochastic forces. We elaborate that a role of pre-adaptation to anthropogenic disturbance in plant invasion success should thus additionally be validated based on the analyses of archaeobotanical remains. Such materials, in the light of detailed knowledge on past human societies could highlight fine-scale differences in the type and timing of past disturbances. We propose a combination of archaeobotanical, ancient DNA and morphometric analyses of plant macroand microremains to assess past community composition, and species' functional traits to unravel the timing of adaptation processes, their drivers and their long-term consequences for invasive species. Although such methodologies have proven to be feasible for numerous crop plants, they have not been yet applied to wild invasive species, which opens a wide array of insights into their evolution. [ABSTRACT FROM AUTHOR]

Background: Community-driven invasion, also known as community coalescence, occurs widely in natural ecosystems. Despite that, our knowledge about the process and mechanisms controlling community-driven invasion in soil ecosystems is lacking. Here, we performed a set of coalescence experiments in soil microcosms and assessed impacts up to 60 days after coalescence by quantifying multiple traits (compositional, functional, and metabolic) of the invasive and coalescent communities. Results: Our results showed that coalescences significantly triggered changes in the resident community's succession trajectory and functionality (carbohydrate metabolism), even when the size of the invasive community is small (~ 5% of the resident density) and 99% of the invaders failed to survive. The invasion impact was mainly due to the high suppression of constant residents (65% on average), leading to a lose-lose situation where both invaders and residents suffered with coalescence. Our results showed that surviving residents could benefit from the coalescence, which supports the theory of "competition-driven niche segregation" at the microbial community level. Furthermore, the result showed that both short- and long-term coalescence effects were predicted by similarity and unevenness indexes of compositional, functional, and metabolic traits of invasive communities. This indicates the power of multi-level traits in monitoring microbial community succession. In contrast, the varied importance of different levels of traits suggests that competitive processes depend on the composition of the invasive community. Conclusions: Our results shed light on the process and consequence of community coalescences and highlight that resource competition between invaders and residents plays a critical role in soil microbial community coalescences. These findings provide valuable insights for understanding and predicting soil microbial community succession in frequently disturbed natural and agroecosystems. DpDvMjk1dTeXPyYscPCMZP Video Abstract [ABSTRACT FROM AUTHOR]

Autophagy plays an important role in plant growth and development, pathogen invasion and modulates plant response and adaptation to various abiotic stress stimuli. The biogenesis and trafficking of autophagosomes involve microtubules (MTs) as important actors in the autophagic process. However, initiation of autophagy in plants under microgravity has not been previously studied. Here we demonstrate how simulated microgravity induces autophagy development involving microtubular reorganization during period of autophagosome formation. It was shown that induction of autophagy with maximal autophagosome formation in root cells of Arabidopsis thaliana is observed after 6 days of clinostating, along with MT disorganization, which leads to visible changes in root morphology. Gradual decrease of autophagosome number was indicated on 9th and 12th days of the experiment as well as no significant re-orientation of MTs were identified. Respectively, analysis of α- and β-tubulins and ATG8 gene expression was carried out. In particular, the most pronounced increase of expression on both 6th and 9th days in response to simulated microgravity was detected for non-paralogous AtATG8b, AtATG8f, AtATG8i, and AtTUA2, AtTUA3 genes, as well as for the pair of β-tubulin duplicates, namely AtTUB2 and AtTUB3. Overall, the main autophagic response was observed after 6 and 9 days of exposure to simulated microgravity, followed by adaptive response after 12 days. These findings provide a key basis for further studies of cellular mechanisms of autophagy and involvement of cytoskeletal structures in autophagy biogenesis under microgravity, which would enable development of new approaches, aimed on enhancing plant adaptation to microgravity. [ABSTRACT FROM AUTHOR]

Forests are important ecosystems that face threats from climate change and global environmental shifts, with invasive alien plant species being a significant concern. Some of these invasive species have already become established, while others are in the process of naturalisation. Although forests are a relatively stable ecosystem, extreme weather events increase their vulnerability to change, and clearings left after natural disturbances are particularly susceptible to invasion by alien plant species (IAPS). We created risk maps of two species that have spread rapidly in the last decade: American pokeweed (Phytolacca americana) and the tree of heaven (Ailanthus altissima). We prepared a generalised linear model based on the occurrence data collected within the LIFE ARTEMIS project. Eleven environmental variables were used to determine habitat characteristics. We constructed two models for each species: one covering the entirety of Slovenia and the other specifically for the forested areas in Slovenia, with the latter incorporating forest-specific variables (such as forest sanitation felling and monocultures). We observed the presence of both species at lower altitudes and in close proximity to water sources. American pokeweed tends to occur nearer to railways, while the presence of the tree of heaven is associated with areas lacking carbonate parent material and influenced by land use patterns. In forested areas, the occurrence of American pokeweed is influenced by forest habitat characteristics, such as disturbances caused by extreme weather events or the prevalence of Norway spruce monocultures. In contrast, the occurrence of the tree of heaven is influenced by more general environmental variables, such as altitude and proximity to railways. Consequently, we have generated risk maps for the entirety of Slovenia and separately for forested areas, both of which indicate similar levels of risk, particularly for the tree of heaven. The risk map for American pokeweed highlights numerous vulnerable areas, especially forest edges, which are highly susceptible to invasion. Furthermore, there is a higher likelihood of this species occurring in areas that have undergone sanitation felling. This study suggests that the production of risk maps of IAPS could be improved by focussing on habitat types and taking into account habitat-specific variables. This approach could enhance the early detection and management of these invasive species. [ABSTRACT FROM AUTHOR]

Preserving the dwindling native biodiversity in urban settings poses escalating challenges due to the confinement of remaining natural areas to isolated and diminutive patches. Remarkably scarce research has scrutinised the involvement of institutions, particularly universities, in introducing alien plant species in South Africa, thus creating a significant gap in effective monitoring and management. In this study, the Tshwane University of Technology in Tshwane Metropole, South Africa serves as a focal point, where we conducted a comprehensive survey of alien plants both within the university premises and beyond its confines. The investigation involved the classification of invasion status and a meticulous assessment of donor and recipient dynamics. Our findings encompass 876 occurrence records, revealing the presence of 94 alien plant species spanning 44 distinct families. Noteworthy occurrences among the dominant plant families are Asteraceae and Solanaceae. Herbaceous and woody plants emerged as the most prevalent alien species, with common representation across both sampling sites. A substantial majority of recorded species were initially introduced for horticultural purposes (51%) before escaping and establishing self-sustaining populations (62%). Furthermore, 43 species identified are listed in South African invasive species legislation, with some manifesting invasive tendencies and altering the distribution of native species in the remaining natural areas. The notable overlap in species observed between the university premises and adjacent areas provides crucial insights into the influence of institutions on the dynamics of plant invasions within the urban landscape. This underscores the prevailing gaps in the management of invasive alien plants in urban zones and accentuates the imperative of an integrated approach involving collaboration between municipalities and diverse institutions for effective invasive species management in urban environments. [ABSTRACT FROM AUTHOR]

Soil biotic and abiotic factors can affect the interaction between invasive and native species. However, it is not yet clear how arbuscular mycorrhizal (AM) symbiosis affects the interaction between adult invasive plants and neighboring seedlings. We used an invasive weed (Bidens frondosa) to test the hypothesis that adult invasive plants facilitate the growth of neighboring seedlings through AM symbiosis, and this facilitation can be inhibited by the biological stress of root‐knot nematode infection. The results showed that the height and total biomass of seedlings near the adult plant increased, indicating that the belowground effects mediated by AM symbiosis played a facilitative role. The positive growth response to resource allocation between adult plant and neighboring seedlings through mycorrhizal connection was inhibited when adult plants were infected by root‐knot nematode. Only the total biomass and root–shoot ratio of adult plants were increased, while seedling growth performance did not change. Our results supported the hypothesis that adult invasive plants can facilitate their neighboring seedlings growth through AM symbiosis and the benefits vary with biotic stress on adult plant. These findings provided important evidence to explain the role of AM symbiosis in plant invasion. [ABSTRACT FROM AUTHOR]

This article discusses the challenges posed by non-native forest insects and the importance of risk mapping approaches to address this threat. It highlights the impacts of invasive forest insects on forest health, ecosystem services, and the economy. The article emphasizes the importance of pest risk models and maps in assessing the risk posed by invasive pests and guiding management and surveillance strategies. It also presents various modeling methods and tools that have been developed to predict the phenology, climate suitability, and spread of invasive insects. The article concludes by emphasizing the need for engagement with end users and improving outreach and training to ensure the broader uptake of pest forecasting tools and map products. The given text consists of a list of references and citations related to the topic of invasive forest insects and their impact on ecosystems. The references cover various aspects of the issue, including the ecological and economic impacts of invasive insects, the role of climate change in facilitating their spread, and the development of decision support systems for risk assessment and management. The text emphasizes the need for surveillance and early detection of high-consequence pests and pathogens to prevent their establishment and spread. It also highlights the importance of accurate species distribution modeling and phenology forecasting in managing invasive forest pests. [Extracted from the article]