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Xanthium spinosum (X. spinosum) is a highly invasive weed native to South America and distributed in 17 provinces (municipalities) of China. It has severely negative influences on ecosystems, agriculture, and husbandry. However, few studies have reported on the impact of human activity and climate change on the future distribution and centroid shift of X. spinosum. This study aimed to investigate the potential geological distribution of X. spinosum in China, as well as the distribution pattern, centroid shift, and key environmental factors influencing its distribution, under four future climate scenarios (SSP1-26, SSP2-45, SSP3-70, and SSP5-85) based on the biomod2-integrated model. The results indicated that the suitable habitats for X. spinosum would expand in the future, mainly in Inner Mongolia, Northeast China, and the plateau regions (e.g., Xinjiang and Xizang). Under future climate scenarios, the centroid would shift toward the northwest or northeast part of China, with the SSP2-45-2050s scenario showing the maximum shift distance (161.990 km). Additionally, the key environmental variables influencing the distribution of X. spinosum, including human impact index, bio5, bio7, and bio12, were determined, revealing that most of them were related to human activities, temperature, and precipitation. This study enhances the understanding of the influence of human activity and climate change on the geographic range of X. spinosum. It provides references for early warning and management in the control of X. spinosum. [ABSTRACT FROM AUTHOR]

The pyrolysis of water hyacinth is gaining attention and acceptance as a resource recovery technique due to its availability and economic viability. However, the presence of lignin, one of the three major biomass fractions, presents significant challenges for profitable water hyacinth processing for biofuel production. Fungal pretreatment of water hyacinth for lignin breakdown has been explored but the application of Trichoderma atroviride as a pretreatment for pyrolysis is relatively novel. The efficacy of T. atroviride pretreatment in improving water hyacinth's pyrolytic products using a fixed‐bed reactor was therefore investigated in this study. The optimization process was studied using a central composite design in response surface methodology with Design Expert 13. Delignification of the biomass was established because the elemental analysis showed a 25.42% increase in cellulose content and a 23.40% and 3.37% decrease in lignin and hemicellulose content, respectively. The biomass pretreatment applied influenced the physical and chemical characteristics of the pyrolytic products. The highest pyrolysis oil yield increased by 25.81% at 575 °C and particle size 2290 μm, and the highest char yield decreased by 4.23% at 273 °C and particle size 1500 μm. This research is crucial for policy and research conversations as it offers a scientific basis for the application of T. atroviride pretreatment in biomass pyrolysis technology and emphasizes the optimal utilization of water hyacinths to obtain socio‐environmental benefits. [ABSTRACT FROM AUTHOR]

Ailanthus altissima (Mill.) Swingle (# AILAL) is a significant invasive alien plant (IAP) in the Mediterranean Basin. It was introduced in Tunisia as a street ornamental tree and became naturalized in several urban cities. Thereby, predicting its potential geographic distribution can provide theoretical support for managing its spread. A biomod2 ensemble model (EM) was used to forecast its potential geographical distribution in Tunisia; explore the environmental variables shaping its distribution; estimate its ecological niche dynamic; and understand its migration trajectory under future scenarios. The simulation trials selected four optimal species distribution models: Random Forest, Maximum Entropy, Generalized boosting model and Artificial neural networks. EM increased the precision of fitting and decreased the uncertainty of fitting generated by single models. The mean TSS, and AUC values for the EM were 0.996 and 0.999, respectively. AILAL potential distribution is largely influenced by built-up areas, precipitation of the coldest quarter, grassland areas and mean temperature of wettest quarter. It is well adapted to occur in built-up areas, its natural regeneration was positively associated with dense urban areas and it decreases with the increasing of grassland range areas. It requires an optimal precipitation of 200–600 mm in the coldest quarter, a precipitation of 40–80 mm in the warmest quarter and an optimal temperature in the wettest quarter of 8–11 °C. Its most suitable geographical area in Tunisia is the northern part. Under future climate conditions, these areas are at a high risk of AILAL invasions. Notably, its highest predicted expansion, under the scenarios SSP2.6, is about 140%, 150%, 128%, and 139% for 2030s, 2050s, 2070s and 2090s, respectively. For the SSP8.5 scenario, its expansion could reach about 137%, 142%, 119%, and 74%, respectively. Accordingly, management, control and surveillance actions should focus on the northern part of Tunisia to avert the spread of AILAL. [ABSTRACT FROM AUTHOR]

Protected areas (PAs), particularly those in developing countries such as Nepal, are facing multiple anthropogenic threats including plant invasions. Despite the population-level recovery of some threatened wildlife species in Nepal’s PAs, their habitats have been degraded by invasive alien plants (IAPs). We quantified the threats of plant invasions in Nepal’s PAs by analyzing species checklists, propagule pressure, and climate suitability including potential invasion hotspots (i.e., the area with high potential vulnerability). Altogether 144 alien plant species have established in Nepal’s 20 PAs. They accounted > 10% of the total vascular plants in five PAs of southern lowlands. Seventeen PAs were invaded by 1–20 IAPs. Propagule pressure ranged from high to medium in 12 PAs with the highest level observed in a PA located near Nepal’s capital city. Nearly half of the PAs are at risk of being invaded by additional IAPs because they are climatically suitable for many IAPs already present in Nepal. Potential invasion hotspot accounted for > 50% of the total area in eight PAs; all but one of these PAs lie in southern lowlands. Overall, the results indicate that threat of plant invasions is higher to the southern lowland PAs than in the northern mountainous ones. Nevertheless, the risk of further invasions by additional IAPs is high in both lowland and highland PAs. Policy and management responses commensurate with the scale of plant invasion problems identified here will help achieve national PAs management objectives and consequently meet the global targets such as the Kunming-Montreal Global Biodiversity Framework Target 6. [ABSTRACT FROM AUTHOR]

Cocklebur (Xanthium strumarium L.) is one of the most widespread and abundant invasive plants in East Africa, including Ethiopia. It rapidly forms large stands that displace other plant species. Thus, the current study was conducted to assess the effect of X. strumarium on the herbaceous plant species composition and diversity of rangelands in eastern Ethiopia. The study was conducted in six districts, purposefully selected based on the level of X. strumarium invasion in the rangelands of eastern Ethiopia. A total of 72 sample plots consisting of 36 invaded and 36 uninvaded sites were selected using random sampling methods. Plant species composition and abundance were recorded using a 4 m2 quadrat. The collected data were subjected to univariate and multivariate analyses using R version 4.4.1. A total of 85 plant species were found in the uninvaded sites, whereas the invaded sites contained 57 plant species, reflecting a decline of 32.9%. Species richness, Shannon–Wiener diversity index, Simpson diversity index, and Pielou's evenness indicated that the uninvaded sites were more diverse than the invaded sites. A higher Sorensen and Jaccard similarity index of herbaceous plant species was observed at Haramaya (0.75, 0.60), whereas Sofi exhibited the lowest values (0.29, 0.17). The rank abundance curve also demonstrated that species abundance, richness, diversity, and evenness were greater in the uninvaded sites than in the invaded sites. The results of the NMDS and PERMANOVA also revealed that plant species composition and structure were significantly different between the invaded and uninvaded sites. Consequently, X. strumarium is one of the most dominant invasive alien plant species, and poses a severe threat to species diversity, composition, and structure in the rangelands of eastern Ethiopia. Therefore, effective policy planning, strategic intervention, and the adoption of appropriate control and management practices in the rangeland environment are crucial for mitigating the current impact and preventing potential future challenges. [ABSTRACT FROM AUTHOR]

In Ethiopia, Parthenium hysterophorus (P. hysterophorus) is an invasive alien plant affecting various ecosystems. P. hysterophorus displaces native plant species and causes a serious threat to biodiversity. With this background, we aimed to assess the soil seed bank of P. hysterophorus under major land use types and assess the perception of the community toward the effects of P. hysterophorus on social aspects in the lower Hare watershed. For this study, 210 soil samples were collected from 15 transect lines in grassland, cropland, and forest land use types. Statistical analysis using three-way factorial analysis of variance (ANOVA) was used to analyze the difference in density of P. hysterophorus among various land uses soil depths and sites (P < 0.05). For assessing the perception of local communities regarding the effects of P. hysterophorus, a total of 117 respondents were enrolled and semi-structured and close-ended questionnaires were used for data collection. It was found that all factors, that is, land use, site, and soil depth, significantly affected the soil seed bank density in the lower Hare watershed (P < 0.05). Results indicated that the mean density of seeds was the highest in croplands among the land use types. Meanwhile, the highest mean density of seeds was identified in 0–10 cm soil depth, but the lowest mean density of seeds was identified in 10–15 cm soil depth. The highest seeds were identified at Chano Cheliba, but the density of seeds the lowest in Kola Shera. Moreover, 38.5% of households in Kola Shera and 21.4% of households in Kola Cheliba, but 8.5% of households in Kola Doriga said that it had effects on ecosystem services such as crop yield and livestock production. There should be a need for increased awareness about the density of P. hysterophorus in various land uses and its impacts on native plant species. Seeking for possible solutions such as mechanical control methods in terms of abortion of its seed set and weeding in early vegetative period are among the local people, researchers, and extension workers can use for the management of its invasion, and appropriate control measures can be designed to combat its further invasion and impacts on different land uses of the region.

Road verges can be important habitats for vascular plant communities and the organisms that, in turn, depend on them. However, the plant diversity in Swedish road verges is threatened by the invasive perennial plant Lupinus polyphyllus Lindl. Therefore, this study aimed to investigate the effects of L. polyphyllus on species richness, diversity, and biotic and abiotic characteristics of dissimilar plant communities in road verges. The study was performed in 24 road verges of high nature value (i.e. with high flowering plant diversity) in central Sweden. We selected road verges within two study areas, one dominated by forest (west) and the other by agricultural land (east). In each road verge we established a pair of 1 m2 plots. One plot was dominated by L. polyphyllus while in the other plot L. polyphyllus either had very low occurrences or was completely absent. We investigated whether species richness, effective number of species, and the probability of occurrence of species belonging to three functional groups (based on their competitive ability and affiliation to nutrient rich soil) differed between plots with vs without lupine and if responses varied between the study areas. We found that L. polyphyllus reduced species richness and diversity of plant communities in road verges. However, we found that even though the direction of the effect was similar, the magnitude was strongly dependent on the pre‐existing communities. Community composition differed between the study areas. The study area in the west hosted a lower proportion of competitive species typical for nutrient poor soils compared to the east. We conclude that invasion by L. polyphyllus is a serious threat to vascular plant communities but that the response is context dependent. Communities with high abundance of vulnerable and poor competitive plant species should be prioritised for eradication and control of the invasive. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) present a significant threat to ecosystems and agricultural production, necessitating rigorous monitoring and detection for effective management and control. To realize accurate and rapid detection of invasive alien plants in the wild, we proposed a rapid detection approach grounded in an advanced YOLOv9, referred to as YOLO-IAPs, which incorporated several key enhancements to YOLOv9, including replacing the down-sampling layers in the model's backbone with a DynamicConv module, integrating a Triplet Attention mechanism into the model, and replacing the original CIoU with the MPDloU. These targeted enhancements collectively resulted in a substantial improvement in the model's accuracy and robustness. Extensive training and testing on a self-constructed dataset demonstrated that the proposed model achieved an accuracy of 90.7%, with the corresponding recall, mAP50, and mAP50:95 measured at 84.3%, 91.2%, and 65.1%, and a detection speed of 72 FPS. Compared to the baseline, the proposed model showed increases of 0.2% in precision, 3.5% in recall, and 1.0% in mAP50. Additionally, YOLO-IAPs outperformed other state-of-the-art object detection models, including YOLOv5, YOLOv6, YOLOv7, YOLOv8, YOLOv10 series, Faster R-CNN, SSD, CenterNet, and RetinaNet, demonstrating superior detection capabilities. Ablation studies further confirmed that the proposed model was effective, contributing to the overall improvement in performance, which underscored its pre-eminence in the domain of invasive alien plant detection and offered a marked improvement in detection accuracy over traditional methodologies. The findings suggest that the proposed approach has the potential to advance the technological landscape of invasive plant monitoring. [ABSTRACT FROM AUTHOR]

The intensive invasion of the species Impatiens glandulifera was discovered during a route survey organised in 2023 in the areas where potentially invasive alien plant species was already registered. As determined, the main population has been experiencing a substantial increase since 1991, going from just 10–15 individuals to around 500. Additionally, a separate population of this species was found over 6 km away from the initial locality with over 700 individuals. It is assumed that the species was introduced as an ornamental plant for cultivation on an erf, from where it "escaped" and naturalised in a semi-natural habitat. The paper presents history of the introduction, establishment as well as current status of the discovered populations in Armenia. Hence, further research and monitoring of the entire population are necessary to determine the vector of penetration, predict the further spread of this species, and develop control measures. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Methods Results Main Conclusion We aim to investigate whether invasive alien plants introduced at different times exhibit variations in elevational distribution patterns and to explore the correlations of these patterns with climate, native plants and human activity.Guangxi, China.We recorded plant richness and cover across elevational gradients at 25–34 sites within each reserve, utilising 84–134 roadside plots per site. Using generalised linear mixed model (GLMM), we assessed the impacts of climate, native plants and human activity on the distributions of all, old and new invasive alien plants across the region and within the nature reserves.At regional scales, the cover of all, new and old invasive alien plants decreased with increasing elevation, while only the richness of old invasive alien plants exhibited a similar pattern. Contrasting patterns were observed in Dayao Mountain, where the cover of old invasive alien plants decreased while the cover of new invasive alien plants increased. The richness patterns of all and new invasive alien plants were opposite between Dayao Mountain and Yachang Orchid. Moreover, native plant richness was negatively correlated with the richness of invasive alien plants, while interference intensity positively affected new invasive alien plants at both regional and reserve scales. At the regional scale, native plant richness accounted for 78.27%, 91.94% and 60.9% of all, old and new invasive alien plants respectively. Interference intensity accounted for 33.85% of the variation in new invasive alien plants. Annual mean temperature positively influenced the cover of all and old invasive alien plants at both regional and reserve scales, explaining 36.91% and 74.28% of their regional variation. Additionally, interference intensity and distance to human settlements positively impacted the cover of new invasive alien plants, contributing to 50.95% and 31.92% of their variation at regional scales.The distinct distribution patterns of old and new invasive alien plants highlight the significance of residence time in understanding their dynamics. Climate factors constrain the cover distribution of all and old invasive alien plants, whereas interference intensity and distance to settlements determine the distribution of new invasive alien plants. Notably, native plants play a vital role in preventing the establishment and spread of invasive alien plants within nature reserves, and their effectiveness increases with longer residence times. Our findings highlight the critical importance of minimising human interference and conserving native species for the effective management of invasive alien plants in nature reserves. [ABSTRACT FROM AUTHOR]

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Simple Summary: The water primrose (Ludwigia peploides) is believed to have been planted as an ornamental aquatic plant in South Korea. It spread to natural ecosystems through rivers, and its distribution is gradually expanding in Suwon, Hwaseong, Busan, and Jeju. However, there has been no specific study on the ecological risk of L. peploides introduced into South Korea. This study, therefore, investigates the distribution status and ecological risks of L. peploides in South Korea through field surveys and allelopathic material analysis, as well as assessing abiotic risk factors. The distribution was confirmed at a total of 19 sites. The species was observed to primarily inhabit aquatic environments but were also observed to inhabit moist terrestrial areas such as riverbanks or wet grasslands. The results of this study are expected to aid in the identification of the current distribution and potential ecological risks of L. peploides in South Korea, providing vital information for the development of effective management strategies. The number of alien species introduced into South Korea continues to increase over the years. In particular, several plants have been introduced as ornamentals. Ludwigia peploides, which is native to the Americas and Australia, is believed to have been planted as an ornamental aquatic plant called "water primrose" and "primrose". It spread to natural ecosystems through rivers, and its distribution is gradually expanding in Suwon, Hwaseong, Busan, and Jeju. However, there has been no specific study on the ecological risk of L. peploides introduced into South Korea. This study, therefore, investigates the distribution status and ecological risks of L. peploides in South Korea through field surveys and allelopathic material analysis, as well as assessing abiotic risk factors. The distribution was confirmed at a total of 19 sites, with high-density mats of a single species forming along the water's edge and on the water surface. The maximum distribution area was 13,922 m2 in Chilgok Reservoir in Anseong. Stems and plant fragments transported along waterways were continuously forming colonies through vegetative propagation. When evaluating the overall risk, it is determined that L. peploides has a high potential to cause significant damage to the ecosystem if not managed promptly. Therefore, continuous monitoring is necessary to effectively manage and prevent the habitat expansion of L. peploides. The results of this study are expected to aid in the identification of the current distribution and potential ecological risks of L. peploides in South Korea, providing essential data for ecological risk assessment and the development of effective management strategies. [ABSTRACT FROM AUTHOR]

• Nassella trichotoma is a serious invasive grass in South Africa's Mountain grasslands. • N. trichotoma alters soil nutrients, which impacts reestablishment of native plant species. • N. trichotoma invasion is associated with lower native and higher non-native species richness. • Native plant diversity is reduced by N. trichotoma invasion. Nassella trichotoma (Poaceae) is a highly invasive South American grass that is invading montane grasslands in the Eastern and Western Cape provinces of South Africa. Although N. trichotoma has been recognised as a major problem in these mountains for decades, the primary concern has been on impacts on rangeland productivity and management, while the impacts of invasions on plant biodiversity have not been considered. To understand the impact of N. trichotoma on local plant biodiversity, 81 pairs of plots (total of 162 plots) were laid out in the Sneeuberg and Eastern Cape Drakensberg mountains, Eastern Cape, in March 2020 and March 2021. At each site plots were located in grassland invaded by N. trichotoma and in nearby uninvaded grassland (control). A total of 20 N. trichotoma patches were sampled with two to four plot pairs per site. All vascular plant species were recorded in all plots, the cover abundance of each species per plot was visually estimated, and the topsoil was sampled and analysed for differences in nutrient and physical factors between invaded and uninvaded plots. Plant species diversity was 24 % higher in uninvaded areas, and the native grasses Pentameris airoides (Χ2 = 4.93, d.f. = 1, p < 0.01), Tenaxia disticha (Χ2 = 5.51, d.f. = 1, p < 0.01), and Themeda triandra (Χ2 = 9.28, d.f. = 1, p < 0.001) were significantly less abundant in invaded plots. Uninvaded areas had greater native species diversity (65 species) and fewer alien species (3) than invaded areas (47 and 9 respectively). Of the 18 soil variables measured, the following were significantly higher in invaded areas than uninvaded areas: boron (23 %), calcium (18 %), phosphorous (58 %), silt (10 %), total cations (12 %), and zinc (68 %). This suggest that N. trichotoma alters soil nutrients. The results indicate that N. trichotoma is a powerful driver of native biodiversity erosion in these montane grasslands and should be a cause for major concern by landowners and government. [ABSTRACT FROM AUTHOR]

Invasion by invasive alien plants is a global challenge and South Africa has invested billions of Rands to manage invaders through the Working for Water programme. However, regular monitoring after alien plant clearing is hardly done, yet it forms the basis for assessing clearing programme effectiveness, particularly ecosystem recovery trajectories. I monitored both vegetation and soil recovery 6 years after Eucalyptus grandis clearing by Working for Water at Zvakanaka Farm in Limpopo Province of South Africa. Vegetation diversity and soil physical properties were surveyed in 2019 and re‐surveyed in 2022 on fell‐and‐removal and fell‐and‐stackburn cleared treatments and compared to the nearby uninvaded treatment. Results show a significant increase in species richness in 2022 compared to 2019 in the fell‐and‐removal treatment. Cover of both native trees and shrubs as well as forbs was significantly higher in 2022 compared to 2019 in the fell‐and‐removal treatment compared to the fell‐and‐stackburn treatment. Most secondary invaders such as Acacia mearnsii, E. cloeziana, Lantana camara and Rubus rigidus that frequently occurred in 2019 showed decreased occurrence in 2022 on both cleared treatments. Between the two sampling years, soil compaction improved on the fell‐and‐removal treatment only, whereas hydraulic conductivity increased significantly in 2022 compared to 2019 in both the fell‐and‐removal and fell‐and‐stackburn treatments. Soils that were strongly and severely repellent in 2019 in the fell‐and‐stackburn treatment were becoming slightly repellent in 2022. These results show varied vegetation and soil improvements between 2019 and 2022 in both the fell‐and‐removal and fell‐and‐stackburn cleared treatments an indication that recovery is moving towards a positive vegetation and soil recovery trajectory in the direction of the uninvaded treatment. Recommendations for successful passive restoration such as secondary invasion follow‐up clearing are discussed. [ABSTRACT FROM AUTHOR]

Klasea quinquefolia (M.Bieb. ex Willd.) Greuter & Wagenitz is a perennial and rhizomatous herb native to the Russian Caucasus, Armenia, Azerbaijan, Georgia, Iran, and Asian Turkey. The natural habitats of the species are deciduous forests or open areas in hill/mountain areas. Outside the native range, the species is mainly known for its ethnobotanical and pharmaceutical uses but in recent years, it has been also recorded as an alien species in Austria. In this work, we reported the first occurrence of K. quinquefolia in Italy. The species was recorded in August 2023 in the Monza Park (Lombardy, N-Italy) in a mesophilous woodland dominated by Carpinus betulus. The new population was subdivided in 10 subpopulations distributed in habitat patches with surface areas ranging from 0.085 to 95,008 m2. The total population accounted almost 500 individuals with a flowering population size of about 350 individuals. Likely, the establishment of K. quinquefolia is linked to the presence of internationally frequented facilities that might have favoured its unintentional arrival (e.g. the Monza Racetrack) or to historical reasons of past introductions to Royal Gardens of the Monza Palace. Presently, it should be treated as a naturalized alien species in Italy even if its further spreading could be favoured by the species' habitat preference and climate change. [ABSTRACT FROM AUTHOR]

The present study deals with an exploratory survey on the uses and role of invasive alien species (IAS) in the local Naga livelihoods in the mountainous region of eastern Himalayas. IAS was randomly sampled from an anthropogenic disturbed forest and a community protected forest to comparatively analyse the type of IAS prevailing in those conditions. Later, group discussions were arranged with local inhabitants to distinguish and identify the various uses of IAS. A total of 31 plant species belonging to 18 different families were identified, out of which 21 species were reported to be used as bio-resources. The majority of the identified species were found to possess medicinal or curative properties. Considering the importance of IAS despite some of their negative impacts, it is important to impart traditional knowledge of their uses to the upcoming generations and initiate necessary steps to distinguish harmful species from harmless ones for better ecological sustenance. [ABSTRACT FROM AUTHOR]

Plant invasions threaten the biodiversity of islands, causing serious impacts on their ecosystems. To investigate the distribution patterns of invasive alien plants on subtropical islands, the environmental determinants of species richness, and the growth forms of invasive alien plants, this study analyzed the composition and origin of invasive alien plants on 77 islands in Fujian. The similarity in the distribution of invasive alien plants between islands was assessed using the UPGMA. Moreover, feature selection, best-subset regression, and variance decomposition were performed using 19 environmental variables characterizing climate, anthropogenic disturbance, and landscape/geography, as well as the species richness and growth forms of invasive alien plants. Through the analysis, the main environmental factors affecting the species richness and growth forms of invasive alien plants on the Fujian islands were identified. The results showed 142 species of invasive alien plants in 38 families and 102 genera on 77 islands in Fujian. Annual herbs constituted the most representative growth form of invasive alien plants and tropical America was the main origin of invasive alien plants. The distribution of invasive alien plants across the 77 islands in Fujian showed a high degree of similarity, suggesting a nested pattern in their distribution. The proportions of building and farmland area (BFA), island area (A), and maximum elevation (ME) were the main driving factors of species richness and growth forms for invasive alien plants. In particular, BFA played a key role in driving plant invasion. The results of this study can help establish an early warning mechanism for invasive alien plants and better implement island ecological management, which are important for the protection of subtropical island ecosystems. [ABSTRACT FROM AUTHOR]

Xanthium spinosum (X. spinosum) is a highly invasive weed native to South America and distributed in 17 provinces (municipalities) of China. It has severely negative influences on ecosystems, agriculture, and husbandry. However, few studies have reported on the impact of human activity and climate change on the future distribution and centroid shift of X. spinosum. This study aimed to investigate the potential geological distribution of X. spinosum in China, as well as the distribution pattern, centroid shift, and key environmental factors influencing its distribution, under four future climate scenarios (SSP1-26, SSP2-45, SSP3-70, and SSP5-85) based on the biomod2-integrated model. The results indicated that the suitable habitats for X. spinosum would expand in the future, mainly in Inner Mongolia, Northeast China, and the plateau regions (e.g., Xinjiang and Xizang). Under future climate scenarios, the centroid would shift toward the northwest or northeast part of China, with the SSP2-45-2050s scenario showing the maximum shift distance (161.990 km). Additionally, the key environmental variables influencing the distribution of X. spinosum, including human impact index, bio5, bio7, and bio12, were determined, revealing that most of them were related to human activities, temperature, and precipitation. This study enhances the understanding of the influence of human activity and climate change on the geographic range of X. spinosum. It provides references for early warning and management in the control of X. spinosum.

The ability to balance the allocation of resources between growth and reproduction as a response to stress factors, can be an advantage for plants in disturbed environments. Invasive alien plants (IAPs) often show high levels of phenotypic variability in resource allocation, a key trait that plays a crucial role in their success to invade new areas. Control management for IAPs must consider this capacity in the development of effective strategies. In this study, we performed continuous measures of leaf growth and reproductive traits of Cortaderia selloana, an IAP of global concern, and applied generalised linear models (GLMs) to evaluate trade‐offs between vegetative growth, leaf composition and reproductive success at different cutting moments. Cutting moment, but not flowering, affected the length of the vegetative growth period (VGP) and average growth rate (AGR), and the interaction with flowering affected AGR and final leaf length (vegetative growth total, VGT). Specific leaf area (SLA), leaf nitrogen (N) content and the isotopic value of δ13C were affected by cutting, and N was also affected by flowering and the interaction with cutting time. Silica also showed a negative correlation with leaf carbon (C) depicting a trade‐off between both structural components. Cortaderia selloana successfully adapted its leaf growth and composition to cutting moment, but this was also modulated by flowering. Moreover, the species is dioecious, and its response may differ between female and hermaphroditic plants. This suggests flexible trade‐offs in resource allocation, therefore the time for cutting must be precisely scheduled to suppress flowering. [ABSTRACT FROM AUTHOR]

Improving success rates of classical weed biocontrol programs is an ongoing effort that requires a variety of different approaches. Previous assessments indicated biocontrol agent taxonomy and feeding characteristics and weed life history traits are associated with better control outcomes. We examined weed biocontrol releases for correlations between biocontrol agent and target weed traits associated with different levels of reported establishment and control. Data collated in the 5th edition of 'Biological Control of Weeds: A World Catalogue of Agents and Their Target Weeds' were used as the basis for this global analysis. Published literature was used to augment the catalog with data for eight biocontrol agent traits and four target weed traits. Biocontrol agent establishment and impact data were analyzed against these traits using generalized linear mixed models and categorical models, respectively. Analyses for biocontrol agent establishment reveal the following agent traits were correlated with a greater probability of establishment: being an internal feeder, feeding on above-ground plant tissues, multivoltine agents and agents that feed during both their adult and immature life stages. Insect taxon did not affect establishment except for the order Lepidoptera, which had the lowest establishment probability. For weed traits, those occurring in aquatic or riparian habitats were associated with a higher probability of biocontrol agent establishment. Regarding agent impact, using the definition categories in the catalog, agents feeding externally and on vegetative plant tissues, multivoltine agents and those with both adult and immature plant-feeding life stages were strongly correlated with greater impact. Perennials, reproducing only vegetatively and invading aquatic or riparian habitats were associated with greater biocontrol impact. Our findings could facilitate both the prioritization of invasive plants targeted for biocontrol and the selection of suitable biocontrol agent candidates, which should further improve biocontrol project outcomes. [ABSTRACT FROM AUTHOR]

A cost benefit analysis of all weed biocontrol in New Zealand (NZ) was undertaken, using available data, to support future funding decisions by stakeholders. The analysis showed that 2022 investment in weed biocontrol in the productive sector was NZ$0.69 million, yielding an annual benefit of NZ$85 million (potentially reducing to NZ$57 million to avoid double-counting where biocontrol suppressed a secondary invasive weed that only became a problem because an earlier weed was biologically controlled). In contrast, 2022 investment in environmental weed biocontrol was NZ$0.65 million, yielding a slightly negative economic return of NZ$0.56 million. Historically, from 1926 to 2022, the overall benefit–cost ratio for all weed biocontrol in NZ (calculated from present values, discount rate 4%) was strongly positive (155:1) for productive sector weeds (or 110:1 with secondary weed invasion). In contrast, for environmental weeds, the overall benefit–cost ratio (0.88:1) showed a negative return on investment (based on relatively easily quantifiable, market-based measurements). Conclusions were robust to sensitivity testing of key parameters. Benefits from weed biocontrol in the productive sector (increased pasture productivity, or reduced weed control costs) were relatively straightforward to calculate. In contrast, the economic benefits of weed biocontrol of environmental weeds were hard to quantify because data were difficult to source or did not exist, and intended benefits were environmental such as biodiversity conservation or restoration of ecosystem services, which remain a challenge to monetarise. Until an acceptable method for monetarising environmental benefits becomes available, strictly economic benefit–cost analyses, based on relatively easily quantifiable, market-based measurements, of environmental weed biocontrol programmes seem of questionable value. [ABSTRACT FROM AUTHOR]

Biological invasions can have major social-ecological consequences for rural communities across the world. However, the dimensions (characteristics, infestation and socio-ecological impacts) of emerging invasive alien plants are often less known and urgent information is needed to guide policy and management. In light of this, this paper assesses the social-ecological impacts of Vernonanthura polyanthes, an emerging invasive alien plant found in a Zimbabwean upland landscape which supports conservation and livelihoods. The paper employs qualitative methods—community mapping, time series analysis, and key informant interviews—involving individuals from diverse socio-economic backgrounds, to examine the socio-ecological and economic implications of V. polyanthes and its management in Chimanimani, Zimbabwe. We found that there are nuanced perspectives regarding this invasive alien plant among different socio-economic groups in the region who have different experiences of living with V. polyanthes. Some are embracing it for apiculture, firewood, and ethnomedicine while, on the other hand, some see the tree as negatively affecting key livelihoods (crop farming, pastoralism, and tourism) that are common in the region. Local people also identified that V. polyanthes is associated with ecological impacts that include loss of biodiversity, promoting pests, and negatively affecting watersheds and associated water sources. These mixed experiences concerning the plant are leading to different management practices, in turn inducing some conflicts among various actors. Based on our findings, we suggest more should be done to better manage this invasive alien plant in the region before negative impacts become too great, particularly in protected areas. [ABSTRACT FROM AUTHOR]

• The introduction history, extent of naturalization and drivers of invasion success was assessed for Myoporum in South Africa. • We confirm the presence of M. insulare, M. laetum and M. montanum in the country (listed in decreasing order of range size). • Myoporum species are at a relatively early phase of expansion in South Africa, indicating a substantial invasion debt. • Myoporum insulare is naturalizing and invading most rapidly. Myoporum is a genus of trees and shrubs native to the Northern Hemisphere that has been introduced to many parts of the world, mainly for ornamental purposes. We assessed the introduction history, distribution, and extent of naturalization/invasion for Myoporum species in South Africa. Information was collated to determine key events associated with the introduction, establishment, and naturalization of Myoporum in South Africa. Data were collated to determine the current distribution of the genus in South Africa. Twenty sites in the Western Cape were sampled to determine correlates of naturalization. Myoporum was first recorded in South Africa in 1934. Three species were confirmed to be present in South Africa: M. insulare, M. laetum and M. montanum (37 %, 25 % and 24 % of all iNaturalist records respectively). Most records are from the Western Cape (91 %) and small parts of the Eastern Cape; isolated populations occur in Gauteng and the Northern Cape. We could not confirm the presence M. petiolatum, M. tenuifolium or M. tetrandrum. Field surveys revealed widespread naturalization of M. insulare (46 % of all Research Grade observations in iNaturalist); this species was categorized code D1 in the introduction-naturalization-invasion continuum. Myoporum laetum (C3) and M. montanum (C2) are also widely naturalized but over smaller areas. Naturalized populations comprised predominantly juvenile M. insulare plants occurring in highly disturbed (transformed) habitats. Formal risk analyses for all Myoporum species in South Africa are needed as the basis for re-evaluation of their status in national legislation. [ABSTRACT FROM AUTHOR]

Biological invasions has caused significant damage to the ecological environment and economy of the world. Pest risk assessment is the most cost-effective means of preventing biological invasions to identify potentially suitable indexes for constructing pre-border weed risk assessment methods for China, we screened 80 metrics derived from 53 plant characteristics known to be related to invasive alien plants in other parts of the world and tested whether these metrics differed significantly between two groups of 103 invasive alien plants and 107 non-invasive plants in China. The results showed significant differences in 30 characteristics between invasive and non-invasive plants in China. Compared to the non-invasive plant group, the invasive plant group in China had a greater proportion of (1) plants native to the Americas, (2) plants belonging to the Asteraceae family, (3) polyploid plants, and had (4) a smaller proportion of plants propagated asexually only. The 30 metrics with significant differences were selected for LASSO regression to develop a predictive model to determine how well the metrics could distinguish between invasive and non-invasive alien plants already present in China. Finally an optimal model with 18 metrics was screened out. The optimal model was able to accurately discriminate 75% of non-invasive plants and 90% of invasive plants on the test set. Therefore the present study screened a range of useful metrics for the identification of invasive plants in China, and the high discriminative power of our models indicates that the subset of 18 variables retained in the final model could be useful for establishing a pre-border invasive plant screening tool for China in the future. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) present a significant threat to ecosystems and agricultural production, necessitating rigorous monitoring and detection for effective management and control. To realize accurate and rapid detection of invasive alien plants in the wild, we proposed a rapid detection approach grounded in an advanced YOLOv9, referred to as YOLO-IAPs, which incorporated several key enhancements to YOLOv9, including replacing the down-sampling layers in the model’s backbone with a DynamicConv module, integrating a Triplet Attention mechanism into the model, and replacing the original CIoU with the MPDloU. These targeted enhancements collectively resulted in a substantial improvement in the model’s accuracy and robustness. Extensive training and testing on a self-constructed dataset demonstrated that the proposed model achieved an accuracy of 90.7%, with the corresponding recall, mAP50, and mAP50:95 measured at 84.3%, 91.2%, and 65.1%, and a detection speed of 72 FPS. Compared to the baseline, the proposed model showed increases of 0.2% in precision, 3.5% in recall, and 1.0% in mAP50. Additionally, YOLO-IAPs outperformed other state-of-the-art object detection models, including YOLOv5, YOLOv6, YOLOv7, YOLOv8, YOLOv10 series, Faster R-CNN, SSD, CenterNet, and RetinaNet, demonstrating superior detection capabilities. Ablation studies further confirmed that the proposed model was effective, contributing to the overall improvement in performance, which underscored its pre-eminence in the domain of invasive alien plant detection and offered a marked improvement in detection accuracy over traditional methodologies. The findings suggest that the proposed approach has the potential to advance the technological landscape of invasive plant monitoring.

Climate is one of the key factors governing the biological invasions of alien species, thus its change may have significant consequences for the scale of this process. We analyzed the predicted influence of climate change on the invasiveness of alien species in Poland and identified species susceptible to climate change. A total of 60 species of alien plants and 58 animals were assessed through an expert elicitation process. For 79 species climate change was assessed as the factor enhancing the likelihood of introduction, establishment, spread and/or impact in the future. Currently, the majority of these species are not widespread in Poland, and this list includes species totally absent, or present only in cultivation and captivity. Climate change will increase the number of high-risk invasive alien species (IAS) from 38 to 63. Species originating in warmer parts of the world are most susceptible to climate change. The majority of the high-risk IAS are regulated under the EU and Polish legislature. However, no restrictions have been imposed on some of the high-risk IAS. Since climate change will further increase their invasiveness, implementation of legal provisions towards these species is recommended.

Background and aims: Biological invasions are causing massive environmental, social, and economic impacts worldwide. Understanding the ecological factors that affect the regeneration of invasive plants is critical to develop action plans based on empirical biological evidence. In this study, we investigate ecological limits in the regeneration of Cortaderia selloana, an invasive species with a strong impact in temperate regions. Methods: We sampled 22 sites invaded by C. selloana along an environmental gradient in northern Spain to evaluate the influence of flower predation, environmental stress, and transgenerational effects on the performance of C. selloana offspring. Key results: We found that over half of the sampled flowers per individual contained larvae of Spanolepis selloanae, a recently discovered predator of C. selloana. This finding suggests that the presence of this natural enemy extends over a larger area than previously thought, which might drastically reduce seed production. A common-garden experiment conducted with over 5,200 seeds revealed that seed germination is significantly enhanced with increasing temperatures (with an optimum temperature of 22/12 °C day/night temperatures), and that seedling survival and growth are highest under waterlogged soil conditions. Our experiments also suggest that the minimum temperature for germination of C. selloana is 10 °C, and that seedlings can survive up to one month without water. These findings can improve management programs by delineating which areas are at high risk of invasion and which ones are unsuitable for the regeneration of C. selloana. We also found that seed mass and maternal plant size are positively correlated with seed germination and early seedling growth. Progeny from dry maternal environments performed better under continuous drought conditions and the opposite was found under wet conditions. Conclusions: Overall, our results suggest that flower predators, environmental stress, and transgenerational effects have complex and profound effects on early demographic stages of C. selloana, influencing seed production, seed germination, seedling growth, and seedling survival.

Ecological infrastructure (natural ecosystems that provide important services and save on built infrastructure costs) can have an important role in securing water supply, particularly in water-scarce areas, but this importance is not reflected in investment decisions, partly due to a lack of evidence. In South Africa, one of the main threats to water supply is the proliferation of woody invasive alien plants which significantly reduce stream flow and water yields. We used existing spatial data and estimates of the impact of woody invasive plants on flows and water yields and on restoration costs to analyse the viability of investing in ecological infrastructure at the scale of major water supply areas. The analysis involved comparison of the costs and effects on water yields of catchment restoration with those of planned built infrastructure interventions designed to meet increasing water demands in the medium to long term. The cost-effectiveness analysis used the unit reference value as a measure of comparison, which is based on the discounted flows of costs and water supplied over a defined time. Restoration could supply 24% of the combined yield of planned built infrastructure interventions by 2050, and is not only cost-effective but has the added advantage of a range of co-benefits delivered by improving ecosystem health. This finding suggests that investing in ecological infrastructure should be considered ahead of new built-infrastructure projects. Significance: • Clearing invasive alien plants from South Africa’s main water catchment areas could increase water yields by 997 million m3 by 2050 relative to a business-as-usual approach, equivalent to a quarter of the yield gains through implementation of built infrastructure interventions planned over the same period. • Invasive alien plant clearing would be more cost-effective than built infrastructure interventions in all water supply systems, except one, the Orange River System. • These findings add to the growing body of literature that advocates for ecological infrastructure investments to secure hydrological ecosystem services.

This study aimed to investigate the structure and distribution of invasive alien plants in Jinyun County by surveying various towns and villages and analyzing literature data. The research results revealed that there were 59 species of invasive alien plants in Jinyun County, belonging to 25 families and 48 genera. The most prominent family was Asteraceae, with 20 species, accounting for 33.9% of the total species. Moreover, 46 species were originally from America, accounting for 78.0% of the total. Alternanthera philoxeroides, Alternanthera philoxeroides, Erigeron canadensis, Impatiens balsamina, Bidens pilosa, Phytolacca americana, Ageratum conyzoides, and Euphorbia maculata are the most widely distributed species. The presence of various invasive alien plants in Jinyun County has already impacted the ecological diversity of local species. The study provides a detailed investigation into the types and distribution of invasive alien plants in Jinyun County, which can serve as a basis for developing strategies to control invasive alien species and protect ecological and species diversity. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) have serious environmental and economic impacts, especially in vulnerable areas of China. However, IAP richness distribution patterns, their driving factors, and the dynamic shifts in potential distribution areas remain elusive. We assessed IAP richness distribution patterns and drivers using 402 IAPs recorded in China at 88 926 occurrence points, and then predicted their potential distribution areas. The results show that IAP hotspots were mainly located in southeastern China, especially coastal areas of the South and East and large inland cities. Population density, gross domestic product (GDP), and four climate variables associated with precipitation and temperature jointly influenced the richness distribution pattern of all IAPs. Specifically, population density and GDP impacted the richness distribution pattern of narrow‐range IAPs, and population density, GDP, distance to the nearest national highway, and five climate variables affected the richness distribution pattern of widespread IAPs. Only GDP contributed significantly to the richness distribution pattern of the top 5% hotspot grid cells, whereas population density, GDP, and precipitation in the driest month (BIO14) significantly influenced the richness distribution patterns of hotspots for both the top 10% and top 20%. Prediction analysis demonstrated that southeastern China would have particularly high invasion risk under both current and future climate scenarios. Regions with increases in predicted species richness are more common (44.83–64.97%) than those with decreases, except under the Representative Concentration Pathway (RCP) 4.5 scenario. Climate change will contribute greatly to the expansion of potential IAP distribution areas under both optimistic (RCP 2.5) and pessimistic scenarios (RCP 8.5). The results of this study provide insights into the priority management of IAPs by developing promising strategies for the control and prevention of IAP invasion. [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]

The growth of Heteranthera reniformis, an invasive alien paddy weed, can be affected by cultivation practices. The experiments were conducted using herbicide-free soil to understand the effects of irrigation regimes and nutrient treatments on the growth of H. reniformis, as well as yield parameters while competing with a pre-existing seedbank. The pot experiments were conducted in a randomized complete block design (RBCD) with three replicates and twelve treatments. The four irrigation regimes (IRs): continuous irrigation (CI), soil condition at near saturation (non-puddled) (S), alternate wetting and drying (AWD) irrigation under two conditions [rewatered when the soil water potential reached −25 kPa (25P) and −35 kPa (35P)], and three nutrient treatments (NTs) of 0–0–0 NPK (NT0), 40–25–30 NPK (NT1), 80–50–60 NPK (NT2), kg ha−1 were established. The IRs had a significant effect on the growth of H. reniformis and other paddy field weeds, and the growth of H. reniformis was suppressed in the AWD regimes. NT2 resulted in more rice panicles, higher grain yield, and increased irrigation water use efficiency (IWUE). The highest grain yield and protein content were observed in S–NT2 and 25P–NT2 treatments. The IR and NT can be maintained to prevent yield penalties and reduce the invasiveness of weeds. [ABSTRACT FROM AUTHOR]

Biological invasion is triggered by human development activities such as the construction and expansion of road networks. Road verges serve as important habitats and corridors for the distribution of invasive alien plant species (IAPS) between geographically distant habitats. However, the trajectory of plant invasion and the data regarding the impact of roads on IAPS distribution are relatively poor in Nepal. Here, we surveyed two road types (main roads and feeder road) in the Middle Mountain region of central Nepal in order to investigate how different road types are driving the dispersal of IAPS along road verges and the adjacent natural habitats. Systematic sampling was conducted at ca 2.5 km intervals along the roads. At each sampling site, paired plots (25 m × 4 m) were sampled: one adjacent to and along the road, and another 20 m away and parallel to it in the interior habitat. Our results revealed that the main road verges had a higher cover (33%) and a larger number of IAPS (14 species) than the feeder road (25%; 10 species). The IAPS cover and richness were significantly higher along verges than in the adjacent interior habitats for both road types, indicating that roads are contributing as corridors for the dispersal of IAPS in the Middle Mountain areas of central Nepal. Further, elevation, tree canopy, and disturbances (grazing/mowing/trampling) were found to be the key factors that determine spatial distribution of IAPS along road verges. We emphasize that regular monitoring of vegetation along the road verges can help with the early detection and control of potential IAPS in the region before they become problematic. [ABSTRACT FROM AUTHOR]

This paper presents the invasive alien plant species in the Polog region, North Macedonia. As a result of the floristic research of this area, during the period 2021-2023 and based on the preliminary data of local and foreign botanists, 12 invasive alien plant species have been found, 7 of which belong to the Asteraceae family, while the other species belong to the following families: Solanaceae, Fabaceae, Amaranthaceae, Anacardiaceae and Poaceae. Excepting the species Sorghum halepense (L.) Pers., native to northeast Africa (and, probably, western and central Asia), all the other invasive plant species identified in the study region are of American origin (North, Central and South America). The alien invasive species identified in the Polog region belong to three life forms, where Therophytes (T) predominate (66.66%) among the identified species, while Geophytes (G) and Phanerophytes (P) represent only 16.67% each. [ABSTRACT FROM AUTHOR]

Plantations, and associated invasions, of exotic Pinus trees occur extensively in the southern hemisphere, threatening the persistence of biodiverse Mediterranean‐climate vegetation. Large‐scale decommissioning of such plantations in the eastern Cape Floristic Region (South Africa) enabled a wide‐ranging study showing successful passive restoration of fynbos vegetation after afforestation. Using a paired study design, we compared the diversity, and floristic and growth‐form composition of post‐fire recovering fynbos in former plantations with that in recently burnt neighboring fynbos in a natural state within the Garden Route National Park. The fynbos of the study area showed good autogenic recovery after several decades of pine afforestation and a fire subsequent to the clearcutting of these trees. On average, native plant abundance and species richness (particularly of shrubs) were significantly lower, and non‐native plant species richness significantly higher, in former plantation areas than in natural fynbos, but these differences were small. Species diversity (Shannon–Wiener index) did not differ significantly between the two vegetation states. The former plantations harbored 91% of the number of native species that the natural fynbos had, while the similarity of the two floras was 65%. Non‐metric multidimensional scaling ordination and multivariate generalized linear models accordingly showed no clear distinction in community composition between the two vegetation states. We concluded that the restoration potential of the montane grassy fynbos in the study area is superior to that previously documented in montane proteoid fynbos, and that fire and invasive alien plant control after clearcutting of the plantations is essential to promote fynbos restoration. [ABSTRACT FROM AUTHOR]

Ageratina adenophora and Chromolaena odorata belonging to the family Asteraceae are the two most noxious invasive alien plant species in the natural forests of Mizoram, a part of the Indo-Burma biodiversity hotspot. These two noxious invasive species should either be controlled by eradication or managed by exploiting them as a resource for bioprospecting like antimicrobial medicines. The present study has explored the two abundantly available invasive species, for bioprospecting and investigating their antimicrobial potential. The obtained results revealed the presence of varying amounts of flavonoids, steroids, tannins, and alkaloids in the polar and non-polar solvent extracts of A. adenophora and C. odorata. The methanol extract of A. adenophora revealed promising antifungal activity against the test plant pathogenic fungi whereas petroleum ether extract of A. adenophora and C. odorata exhibited significant antibacterial potential against both Gram-positive and Gram-negative test bacteria. The results also revealed the solvent extracts of the studied invasive alien plants exhibited almost similar or more effectiveness with that of commonly used synthetic antifungals like Bavistin and broad-spectrum antibiotics like Gentamicin. Investigating the minimum inhibitory concentration of the plant extracts revealed their effectiveness even at minor concentrations. Therefore, the antimicrobial property of these two noxious invasive alien plant species can be recognized as a beneficial resource for medicinal as well as economic purposes for antibacterial and antifungal materials.

Water hyacinth, Pontederia crassipes, is a highly invasive plant native to South America and one of the most invasive aquatic plants in the world. For its control, the planthopper Megamelus scutellaris Berg (Hemiptera: Delphacidae), a phloem feeder also native to South America has been introduced to the USA and South Africa. Considering predicted climate change scenarios, understanding their impacts on biological control agents is crucial. An intriguing yet scarcely explored subject, is the effect of climatic changes on the obligate endosymbionts associated with sap-sucking feeders. Planthoppers establish an obligate relationship with yeast-like symbiotes (YLS), unicellular fungal microorganisms that play an important role in their development, providing missing nutrients in their diet. Considering that increased atmospheric CO2 affects plant chemical composition, this might have a direct impact on their insect host and on their number of YLS. We evaluated the effect of two different CO2 environments: current (cCO2 − 400 ppm) and elevated (eCO2 − 800 ppm) on the abundance of YLS (number of YLS cells/insect) of M. scutellaris, as well as the, age structure, sex, and weight of insects. Heavier females harbored more YLS under eCO2 which underscores the importance of the interaction of CO2 levels and insects’ weight in shaping the abundance of YLS. Additionally, there was a significant increase in the total abundance of insects for instars III to V and adults under eCO2 conditions. However, male number significantly exceeded that of females under both CO2 conditions. Our results suggest a potential positive impact of eCO2 on M. scutellaris populations, which could, in turn, enhance the control of P. crassipes.

Many alien tree species were introduced into grassland ecosystems in South Africa by the commercial forestry industry for paper and timber for furniture. Over decades some of these introduced species escaped into neighbouring farms and community land. Adult trees from these alien species now provide other ecosystem services, notably fuelwood. Depending on the spatio-temporal context, many of these species can also negatively affect ecosystem services. We collected interview data from commercial and communal farmers in the upper Umzimvubu catchment in South Africa to compare farmers' knowledge and perceptions of invasive wattle species invasion and their associated ecosystem services and disservices. Fuelwood and fencing poles were the most common uses of wattle by commercial (83%; 67%) and communal (99%; 49%) farmers. On the other hand, the reduction of grass cover and loss of grazing land were the most commonly mentioned negative impacts of wattles by commercial (83%; 75%) and communal (92%; 80%) farmers. Although both groups recognise the importance of wattles in providing ecosystem services, most communal farmers perceived wattles to have more negative effects than benefits. The findings demonstrate that both farmer groups highly depend on ecosystem services and are affected by disservices of wattles. However, while large-scale commercial households favour the presence of wattles in the landscape, communal households prefer complete removal of the wattles from the landscape. This may be due to lack of locally available alternative options or inability to replace or purchase ecosystem services affected by wattles from other sources or markets like commercial farmers. [ABSTRACT FROM AUTHOR]

Key message: Exotic tree species Syzygium cumini and Taliparti tiliaceum affect restinga forest regeneration growing under them, in comparison to native species, mainly because they reduce saplings' abundance. Biological plant invasions are a considerable threat to native vegetation biodiversity, mainly when the invaded site consists in suppressed fragmented remnants surrounded by urbanization. Although this is the case of Brazilian restinga forests, knowledge on potential invasion events in these environments remains scarce. We herein identified differences between these communities by comparing natural regeneration on plots planted with exotic tree species Syzygium cumini and Talipariti tiliaceum to those planted with native trees on an urban restinga forest park in Rio de Janeiro city. We observed that natural regeneration communities were impacted by exotic trees, resulting in alterations to both their structure and floristic composition. Furthermore, the magnitude of this impact depended on the identity of the exotic tree in question. Somehow, plant community regeneration based on species T. tiliaceum was significantly different from that in native plots, at all parameters: species richness, mean abundance of individuals, mean plant height, total basal area, absolute density and abundance of seedlings. S. cumini, in its turn, seemed to have only significantly changed regeneration's abundance parameters. Therefore, based on our findings, S. cumini and T. tiliaceum presented potential invasive impact to native flora. These species should be monitored and likely managed in other restinga forests, since prevention is the key action to preserve our native environments from biological invasions. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) are recognized as major threats to the environmental and ecological systems with great potential to disrupt global biodiversity, forestry, livelihood, and human health. Nevertheless, ecological and socio-economic investigations of IAPs to facilitate restoration strategies are insufficient in many species. The potential risks posed by Tithonia diversifolia (Hemsl.) A. Gray, an emerging Asteraceae IAP has scantily been addressed in terms of its nature and/or impacts (e.g., phytochemistry, allelo/aroma-chemicals, chemical ecology, livelihood, and human well-being). This review aims to provide a first-hand assessment on potential threats and benefits of T. diversifolia and other Asteraceae IAPs in a multifaceted 'environment-agriculture-energy-health nexus' or 'biorefinery' prospects. Standard methods were used to quest the multifaceted implications of T. diversifolia invasion, mainly in the time frame of 2011 to 2023. Research platforms such as Scopus, Sciencedirect, and Google Scholar facilitated the literature collection. Adequate operation of filters was performed in selecting articles (n = 255) to deliver the state of the art knowledge in South Africa and globally. Applications of T. diversifolia are also discussed to cover diverse fields (e.g., agriculture, food industry, pharmaceuticals, bio/ethnomedicine, environmental remediation, bioenergy, biochar production, and phytosynthesis of engineered nanoparticles). An explicit assessment of IAPs can enable a judicial cost-benefit analysis to help determine its ecological economics while pursuing the targets of the United Nations Sustainable Development Goals and Decade on Ecosystem Restoration. [Display omitted] • Invasive alien plants (IAPs) in Asteraceae can exert detrimental impacts on the biodiversity, environment, agriculture, and livelihood. • Reproductive attributes and allelochemic metabolites of T. diversifolia can facilitate their landscape spread. • Biomedical and biorefinery prospects of IAP are explored using T. diversifolia. • T. diversifolia can contribute to agriculture, environmental remediation, and human health facilitating sustainable management [ABSTRACT FROM AUTHOR]

River valleys are known to be of high natural value; however, they are exposed to a strong human influence. Anthropogenic changes are evident in the structure and species composition of plant assemblages; therefore, vegetation is a very good indicator of the state of the environment. Convolvuletalia sepium tall herb communities are a natural component of riverside vegetation; they are protected in the EU (habitat 6430), yet have been very poorly studied, especially in SE Europe. Information regarding the geographical distribution of these communities, and their floristic composition and threats, along with effective conservation and restoration strategies, remains insufficient; therefore, this study was aimed at a comprehensive investigation of tall herbs. The paper presents results of the first detailed study of this group of communities in Montenegro. Classification of 70 vegetation samples (relevés) using the UPGMA produced six clusters corresponding to plant communities which were included in the Dorycnio recti-Rumicion conglomerati. Two of them were ranked as associations: Mentho longifolii-Pulicarietum dysentericae and Rubo sancti-Eupatorietum cannabini, the latter new to science. Others (communities of Rubus caesius, Rubus caesius-Eupatorium cannabinum, Helianthus ×laetiflorus, and Helianthus tuberosus) were left without a syntaxonomic rank. The ordination analysis with the CANOCO software confirmed the authors' hypothesis that the variability of the vegetation patches studied was related to the land use type and river size. Relevés taken in watercourses flowing through built-up areas were dominated by invasive alien species (IAS). Vegetation samples taken in heavily flooded areas, along the Zeta, one of the largest rivers surveyed, had a simplified species composition. Studies in Montenegro should be continued. Moreover, comparative studies of the Convolvuletalia sepium communities described in the Mediterranean region are also necessary. Attention is drawn to the overly narrow interpretation of habitat 6430 in the lowlands, as it lacks a representation of Mediterranean tall herbs. [ABSTRACT FROM AUTHOR]

Palmer Amaranth (Amaranthus palmeri, Amaranthaceae) is one of the most competitive, troublesome, and noxious weeds causing significant yield reductions in various crops. A. palmeri was also a herbicide-resistant weed causing a serious eco-environmental problem. Given that the process of invasion is dynamic, the A. plamer invasion may already be quite severe where invasive species management and surveys are chronically lacking. Predicting the potential habitat of A. palmeri can help to develop effective measures for early warning and long-term detection. However, the invasive history and distribution patterns of A. palmeri in China remain largely unknown. Here, the invasive history and distribution patterns of A. palmeri from 1985 to 2022 in China were reconstructed, and then the potential geographical distribution of A. palmeri was predicted under current and future climate scenarios (SSP1-2.6, SSP2-4.5, SSP5-8.5) using the optimal MaxEnt model (V 3.4.4) and ArcGIS 10.8.2. The mean AUC values of A. palmeri were 0.967. Under the current climate conditions, the suitable habitat areas for A. palmeri reached 1,067,000 km2 in China and were mainly distributed in north and central China. Under the future scenarios, the highly suitable habitats were mainly distributed in Beijing, Tianjin, and Hebei. Under SSP2–4.5, the future suitable areas will reach the maximum and expand to 1,411,100 km2 in the 2060s. The centroid distribution would northwestward extend under future climate scenarios. The human footprint index, mean temperature of the warmest quarter (Bio_10), April wind speed (Wind_4), temperature seasonality (standard deviation × 100) (bio_4), topsoil gravel content (T_gravel), and precipitation of warmest quarter (Bio_18) were key environmental variables affecting distribution and growth of A. palmeri. Climate change would increase the risk of A. palmeri expanding to high latitudes. Our results will help in developing effective strategies for the early warning, prevention, control, and management of A. palmeri in China. [ABSTRACT FROM AUTHOR]