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Invasive alien species represent a major threat to global biodiversity and the sustenance of ecosystems. Globally, mountain ecosystems have shown a degree of resistance to invasive species due to their distinctive ecological features. However, in recent times, the construction of linear infrastructure, such as roads, might weaken this resistance, especially in the Mediterranean basin region. Roads, by acting as efficient corridors, facilitate the dispersal of alien species along elevation gradients in mountains. Here, we investigated how the ecological features and road-associated disturbance in native plant communities affected both the occurrence and cover of alien plant species in Central Apennines (Italy). We implemented the MIREN road survey in three mountain transects conducting vegetation sampling in plots located both adjacent to and distant from the roads at intervals of ~ 100 m in elevation. We then used community-weighted means of Ecological Indicator Values for Europe together with Disturbance Indicator Values applied to plant species of native communities as predictors of alien species occurrence and cover in a machine-learning classification and regression framework. Our analyses showed that alien species' occurrence was greater in proximity to the road where high soil disturbance occurred and in warm- and light-adapted native communities. On the other hand, alien species cover was more strongly related to moderate grazing pressure and the occurrence of nitrophilic plant communities. These findings provide a baseline for the current status of alien plant species in this Mediterranean mountain region, offering an ecological perspective to address the challenges associated with their management under global change. [ABSTRACT FROM AUTHOR]

Despite their strategic importance as biodiversity hotspots and water sources, montane ecosystems are among the most neglected conservation areas. In particular, the monitoring and management of invasive alien plants in this critical biome is limited. This study presents an analysis of long‐term invasive alien plant removal within montane grassland ecosystems, drawing on insights from 25 years of the Working for Water (WfW) program on the northern Drakensberg Escarpment. We assessed the response of vegetation communities to invasive alien plant removal in this region. Using data from the WfW program on clearance activities, expenditure, and re‐visit times, we compared plant species richness, diversity, and composition in sites managed under the WfW program to adjacent patches of pristine vegetation. Results showed minimal variation in species richness between cleared sites and unmanaged sites. However, these vegetation communities remain distinctly dissimilar across sites. These findings suggest the need for active restoration of montane vegetation communities if they are to return to their natural condition and further highlight the need to conserve the remaining habitats for critically endangered species, even in their depauperate state. [ABSTRACT FROM AUTHOR]

The establishment and spread of plants in their native or alien geographical ranges are determined by their germination. This study investigated the impact of different factors on variations in cardinal temperatures. We used the lm procedure and measured the effect size by the Eta-square approach to find the association of different factors (species, ecotypes, origin (native/alien), year, and life cycle) with the cardinal temperatures of 31 species. Our results showed that the base, optimum, and maximum temperatures responded differently to these factors. The base temperature was less impacted by ecotypes compared with the optimum and maximum temperatures, whereas the species had a higher impact on the variation in the base temperature. The effect of the origin of weedy plants on the base temperature was higher than the optimum and maximum temperatures. The effect of the year on the optimum temperature was more prominent than that on the base and maximum temperatures. The results confirmed that weedy alien plants preferred high and narrow ranges of base, optimum, and maximum temperatures and probably will be more problematic in summer crops. The results indicate that alien plants can benefit from warmer conditions in invaded areas at the germination stage. These findings lay the foundation for further studies to elucidate which factors are more important. [ABSTRACT FROM AUTHOR]

One of the characteristic features of urban floras is their homogenization, which is synonymous with the loss of regionally unique species and a reduction in functional diversity. Here we examined the species composition of native and alien species in the flora of Russian cities to identify the contribution of these groups of species to the homogenization and differentiation of urban floras. The results we obtained showed that the species similarity of urban flora depends on the distance between cities—urban flora of geographically close cities have the lowest species dissimilarity. This distance-dependence is highest for neophytes dissimilarity and lowest for archeophytes dissimilarity. Thus, the homogenization of the species composition of the Ural and Volga region urban floras is provided mainly by archeophytes, while a group of neophytes increases the β-diversity of urban flora. [ABSTRACT FROM AUTHOR]

Background. Special attention is paid in many regions to invasive plant species introduced into natural plant communities. Studying the degree of naturalization of Berberis aquifolium Pursh and Daphne laureola L. on the Crimean Peninsula is important because these species are currently observed in different types of forest vegetation, including Protected Areas. Materials and methods. Forest plant communities with B. aquifolium and D. laureola served as the research target. A geobotanical survey was conducted in 2019–2021 using the Braun-Blanquet approach. The JUICE platform and the PC-ORD 5.0 algorithm were employed to perform the cluster analysis, and the PAST 3.26 software for the ordination analysis. Twelve factors were considered: soil humidity (Hd), humidity fluctuation (fH), substrate acidity (Rc), anionic composition (Tr), carbonate content (Ca), nitrogen content (Nt), granulometric (mechanical) composition of the substrate (Ae), illuminance of the community (Lc), thermal regime (Tm), aridity/humidity (Om), cryoregime (Cr), and climate continentality (Kn). Phytoindication technique was used to determine the parameters of ecological niches. Results and conclusion. The communities with B. aquifolium and D. laureola on the Southern Coast of Crimea were found to belong to the Quercetea pubescentis and Erico-Pinetea classes of vegetation. The species appeared to be most widespread in the pine-oak-hornbeam and oak-hornbeam-dogwood forest communities where they occurred mainly along riverbeds, near springs, and along gully bottoms. According to a majority of edaphoclimatic factors, their habitat conditions corresponded to the parameters of the fundamental niches for the studied species, which explains their high degree of adaptation to the natural environments on the Southern Coast of Crimea.

Orenburg Region is located in the South Urals, mostly in the steppe zone and is characterised by various landscapes suitable for many Chenopodiaceae. The species of Chenopodiaceae are present in all major plant communities (saline vegetation, steppes, on limestone, chalk and sand, and as degraded or ruderal communities). In the steppe zone, many native subshrubby species (Atriplex cana, Caroxylon laricinum, Suaeda physophora) playing a crucial role in semi-deserts (known as southern steppes in the recent Russian literature) located southwards of Orenburg Region are locally found, and several annuals (Salicornia perennans, Suaeda spp.) are most common dominants in plant communities. Some typical semi-desert species (Kalidium foliatum, Bassia hyssopifolia, Soda foliosa, Spirobassia hirsuta) are found in the easternmost part of the region.We compiled a checklist of Chenopodiaceae in Orenburg Region, with two new records (Chenopodium virgatum, Corispermum laxiflorum), based on our critical revision, comprehensive inventory of herbarium specimens and documented observations and field research. In total, we report 76 species in the Region, which is the third-highest number of the Chenopodiaceae species compared with other administrative territories of European Russia, North Caucasus and West Siberia. Alien and native taxa are distinguished. Zonal patterns of species distributions are confirmed. A preliminary conservation status is proposed for each native species. Three species are recommended for exclusion from the Red Data Book of Orenburg Region: Petrosimonia triandra (because of its extensive distribution), Kalidium foliatum and Anabasis salsa (because of the lack of actual threat to their populations). Arthrophytum lehmannianum and Salsola rosacea are considered threatened (Vulnerable) because of their restricted occurrence and population size and because their localities are under anthropogenic pressure. Atriplex hortensis, Atriplex rosea, Chenopodium acuminatum, C. karoi, C. praetericola, C. vulvaria, Climacoptera affinis, C. crassa, Halimocnemis karelinii, Salsola paulsenii and Xylosalsola arbuscula are excluded from the checklist, based on various reasons as discussed in the paper. Point distribution maps are provided for each species. Agriophyllum pungens (Vahl) Link is accepted as the correct authorship instead of "M.Bieb. ex C.A.Mey."

Plant invasions have a negative impact on biodiversity and lead to species loss. Although studies on traits promoting invasiveness have been largely developed, comparative studies on germination traits of closely related native versus alien invasive species, which also take into account threatened species, are lacking. We analysed the germination requirements of two congeneric Lindernia species inhabiting paddy field in Northern Italy. Germination tests were conducted exposing seeds of both species across a broad range of temperature and conditions (i.e., cold-wet stratification, dark condition, alternate temperature, gibberellic acid). The invasive L. dubia showed higher and faster germination, occurring over a broader range of temperatures compared to the native threatened L. procumbens, along with a lighter non-deep physiological dormancy. These results show a competitive advantage of the alien species already in the early stages of plant regeneration and provide a comprehensive overview of the germination requirements, necessary for the development of future conservation and management plans. [ABSTRACT FROM AUTHOR]

Range shifts are a key mechanism that species employ in response to climate change. Increasing global temperatures are driving species redistributions to cooler areas. Studies have documented climate change–induced shifts in species distributions. The range shift in three plant species, namely Bellis perennis L., Cannabis sativa L., and Portulaca oleracea L. to the Himalayan highlands of Ladakh, India, is reported for the first time. These species are not native to the region but have naturalized and are currently occurring as large natural populations at multiple sites. By providing detailed information on taxonomic descriptions, habitat characteristics, distribution maps, global distribution and ecology, the study aims to facilitate the identification of these species in the field which is required for early response and timely interventions to prevent them from becoming invasive in the natural habitats of the Himalayan region. [ABSTRACT FROM AUTHOR]

Background: Orenburg Region is located in the South Urals, mostly in the steppe zone and is characterised by various landscapes suitable for many Chenopodiaceae. The species of Chenopodiaceae are present in all major plant communities (saline vegetation, steppes, on limestone, chalk and sand, and as degraded or ruderal communities). In the steppe zone, many native subshrubby species (Atriplex cana, Caroxylon laricinum, Suaeda physophora) playing a crucial role in semi-deserts (known as southern steppes in the recent Russian literature) located southwards of Orenburg Region are locally found, and several annuals (Salicornia perennans, Suaeda spp.) are most common dominants in plant communities. Some typical semi-desert species (Kalidium foliatum, Bassia hyssopifolia, Soda foliosa, Spirobassia hirsuta) are found in the easternmost part of the region. New information: We compiled a checklist of Chenopodiaceae in Orenburg Region, with two new records ( Chenopodium virgatum, Corispermum laxiflorum), based on our critical revision, comprehensive inventory of herbarium specimens and documented observations and field research. In total, we report 76 species in the Region, which is the third-highest number of the Chenopodiaceae species compared with other administrative territories of European Russia, North Caucasus and West Siberia. Alien and native taxa are distinguished. Zonal patterns of species distributions are confirmed. A preliminary conservation status is proposed for each native species. Three species are recommended for exclusion from the Red Data Book of Orenburg Region: Petrosimonia triandra (because of its extensive distribution), Kalidium foliatum and Anabasis salsa (because of the lack of actual threat to their populations). Arthrophytum lehmannianum and Salsola rosacea are considered threatened (Vulnerable) because of their restricted occurrence and population size and because their localities are under anthropogenic pressure. Atriplex hortensis, Atriplex rosea, Chenopodium acuminatum, C. karoi, C. praetericola, C. vulvaria, Climacoptera affinis, C. crassa, Halimocnemis karelinii, Salsola paulsenii and Xylosalsola arbuscula are excluded from the checklist, based on various reasons as discussed in the paper. Point distribution maps are provided for each species. Agriophyllum pungens (Vahl) Link is accepted as the correct authorship instead of "M.Bieb. ex C.A.Mey." [ABSTRACT FROM AUTHOR]

Some biological differences between native and alien plants are relevant to their dispersal mechanisms. One of them is the fruiting period: it is shifted in time, peaking later than in natives. Here we report the case study showing the temporal distance in fruiting phenology between native and alien plants and their seed dispersal via carnivorous mammals. From 2009 to 2011, scats of badgers Meles meles, foxes Vulpes vulpes, martens Martes spp. (M. martes and M. foina) and possibly also raccoon dogs Nyctereutes procyonoides (N = 820) were collected along transects totaling 30.4 km in length each month from June to November. We analyzed the frequency of occurrence of seeds (FO %) and the seed load in sampled scats; 61.7% of the sampled feces contained seeds of 18 fleshy-fruited native and alien plant taxa, and the most abundant seeds were from species with multi-seeded fruits such as Vaccinium myrtillus (94.6%), Rubus sp. (2.0%), and drupes of Prunus serotina (1.0%). The structure of dominance was characterized by seeds of Vaccinium myrtillus (15.0%), Pyrus sp. (14.8%) and Prunus serotina (13.0%) with aliens reaching high frequency of occurrence (FO %). The shares of seed FO % in the samples differed between alien and native plants. For seed load there were also significant interactions between the status of the seeds (alien or native) and the month of the vegetation period. Our data show the coincidence of two factors – the late fruiting period of alien plants and the decreasing availability of native fruits during the vegetation period. Such a set of factors may promote the dispersal of alien plant seeds by carnivorous mammals, which, unlike migrating birds, are constantly present in autumn. The limited availability of native fruits after their fruiting period, creating a phenological gap, makes alien plants the main source of fleshy-fruits at the end of vegetation period in forest ecosystems; this is expressed in high proportion of alien plants in seed FO %, and in significant interactions in the seed load in carnivore scats. [ABSTRACT FROM AUTHOR]

Invasive plant species (IPs) are widespread in forests and cause substantial environmental, economic and social impacts. They occupy native ecological niches, causing local extinctions to the detriment of native biodiversity and disrupting ecosystem services provision. How landscape characteristics may determine the success of IPs remains unclear and, more importantly, how land-use and land-cover changes may result in spatial shifts in the invasion risk. Furthermore, the study of how landscape factors may influence biological invasions has focused on particular species, but not the IPs' community. In this study, we identify and assess landscape variables that influence the presence and distribution of the IPs' community in temperate forests of a global biodiversity hotspot in south-central Chile. We fitted spatially explicit models, combining field-sampling information and landscape variables related to land-use/land-cover, topography, climate, soil characteristics and anthropogenic factors to explain and predict the presence and distribution of the IPs' community. From the whole sampling of plant species, we identified eight plant species classified as IPs: three trees and five shrubs. We used field data from 125 500 × 2 m-transects, in which we registered species richness, abundance and basal area of IPs' community. Distance to forest plantations was the landscape variable with the most substantial influence on IPs' presence and distribution. Richness, abundance and basal area of IPs' trees were higher at shorter distances from forest plantations. The basal area of IPs' trees was the best model explaining the relationship between IPs' community and landscape variables. All descriptors of the IPs' community showed similar spatial patterns: species richness, abundance and tree basal area are higher in more disturbed areas. Our findings contribute to increasing our understanding of the distribution patterns of IPs in forest landscapes. Our models can be suitable tools for designing strategies to prevent, mitigate or make integrated control of the impacts of invasive species in forest landscapes. [ABSTRACT FROM AUTHOR]

The establishment and spread of plants in their native or alien geographical ranges are determined by their germination. This study investigated the impact of different factors on variations in cardinal temperatures. We used the lm procedure and measured the effect size by the Eta-square approach to find the association of different factors (species, ecotypes, origin (native/alien), year, and life cycle) with the cardinal temperatures of 31 species. Our results showed that the base, optimum, and maximum temperatures responded differently to these factors. The base temperature was less impacted by ecotypes compared with the optimum and maximum temperatures, whereas the species had a higher impact on the variation in the base temperature. The effect of the origin of weedy plants on the base temperature was higher than the optimum and maximum temperatures. The effect of the year on the optimum temperature was more prominent than that on the base and maximum temperatures. The results confirmed that weedy alien plants preferred high and narrow ranges of base, optimum, and maximum temperatures and probably will be more problematic in summer crops. The results indicate that alien plants can benefit from warmer conditions in invaded areas at the germination stage. These findings lay the foundation for further studies to elucidate which factors are more important.

Acmella radicans (Jacquin) R.K. Jansen is a new invasive species recorded in Yunnan Province, China, and little is known about its allelopathic potential and allelochemicals. In this study, the allelopathic effects of the essential oil (EO) of A. radicans on seed germination and seedling growth of four common plants, Brassica napus, Brassica rapa ssp. chinensis, Digitaria sanguinalis, and Lolium multiflorum, were explored. The results showed that the seed germination index, germination rate, root length, stem length, and biomass of B. napus and B. rapa ssp. chinensis were significantly inhibited at all EO concentrations of A. radicans, but there was a 'low-promotion and high-inhibition effect' on the root length of D. sanguinalis and L. multiflorum at low concentrations of 0.5 μL·mL−1 and 0.5–1.0 μL·mL−1, respectively. With increasing concentrations of EO, the inhibition rates of seed germination and seedling growth of four common plants gradually increased, and D. sanguinalis and L. multiflorum were the most inhibited, followed by B. rapa ssp. chinensis, and the least inhibited was B. napus. Thirty-two components were identified using GC–MS, representing 99.07% of the EO in A. radicans. The major components were 2-tridecanone (30.46%), caryophyllene oxide (19.18%), 4,8,11,11-tetramethylbicyclo[7.2.0]undec-3-en-5-ol (7.84%), β-caryophyllene (7.67%), and widdrol (4.7%). Among the compounds we identified, (E,E)-2,4-decadienal, 2-tridecanone, γ-cadinene, δ-cadinene, (E)-α-cadinol, spathulenol, caryophyllene oxide, and widdrol have been previously reported as having possible allelopathic effects. Our study was the first to show that A. radicans could potentially release allelochemicals to influence neighboring plants during its invasion and expansion. [ABSTRACT FROM AUTHOR]

The composition and structure of soil seed banks provide insight into the long-term implications of plant invasions on resident communities. The effect of Salpichroa origanifolia (Sa) on the seed bank of a coastal mesophile forest (Tuscany) was studied by growing Sa-rhizomes in soils from low and high invaded sites, in full sun and canopy shade. Sa growth patterns, and the composition, biomass, nitrogen, and phosphorus contents of seedlings which emerged from seed banks were determined. Seed bank abundance and richness were also determined from under and 2 m apart established Sa populations. Sa plants' leaf traits and biomass allocation changed in response to light conditions. The germination of seed bank seedlings was not affected or even promoted by Sa, while their biomass as well as N and P uptake were more than halved in both light conditions, leading to a progressive depletion of the forest seed bank. Richness was lower under established Sa populations. Sa seedlings exerted a greater suppression on residents than Sa adults, and these appeared more competitive against their own seedlings than on residents. Sa is an invader of concern for Mediterranean forests because of its adaptability to shaded conditions, the competitiveness of its seedlings, and its vegetative spread by means of rhizomes. [ABSTRACT FROM AUTHOR]

Aims: Most naturalized plants are escapees from cultivation. Inventories of cultivated introduced species thus offer unique, still underutilized, opportunities to assess naturalization drivers of introduced plants. We used a comprehensive inventory of 13,718 introduced species cultivated in China's botanical gardens to test which species characteristics distinguish the 739 species that have naturalized. Locations: China. Methods: We used generalized linear models to test whether the naturalization of cultivated introduced plants in China is associated with functional traits, propagule pressure, environmental niche and introduction history. To test direct and indirect effects of those variables and their relative importance in driving naturalization, we used structural equation models. Results: We showed that species were more likely to naturalize when they originate from the Americas, are more widely cultivated, and have a longer residence time. Moreover, species were more likely to naturalize if they have a good environmental match, are short‐lived herbs, are predominantly propagated from seeds, and, in the case of herbs, are relatively tall compared to other herbs. Part of the latter effects are mediated by how these variables relate to propagule pressure proxies, and this varies among short‐lived herbs, long‐lived herbs and woody plants. Main Conclusions: Naturalization is partly driven by life‐form‐dependent cultivation biases. [ABSTRACT FROM AUTHOR]

iNaturalist defines itself as an "online social network of people sharing biodiversity information to help each other learn about nature" and it is likely one of the largest citizen science web portals in the world, as every year millions of observations across thousands of species are gathered and collectively compiled by an engaged community of nearly 3 million users (November 2023). The strengths and potentialities that explain the success of the platform are reviewed and include, among others, its usability and low technical requirements, immediacy, open-access, the possibility of interacting with other users, artificial-intelligence-aided identification, versatility and automatic incorporation of the validated records to GBIF. iNaturalist has, however, features that scientists need to carefully consider when using it for their research, making sure that the quality of observations does not limit or hinder its usefulness in plant research. While these are identified (e.g., the lack of representative photographs for many observations or the relatively frequent identification errors), we provide some suggestions to overcome them and, by doing so, improve the use and add value to iNaturalist for plant research. [ABSTRACT FROM AUTHOR]

Ornamental horticulture is a significant contributor to the introduction of invasive plant species, such as Impatiens glandulifera. Native to the temperate and humid regions of Asia, particularly the Himalaya Mountains, the species was first reported in Europe in 1839, introduced for ornamental and nectar-producing purposes. Its presence in Romania dates since 1882. Over the past few decades, the species' invasive nature has led to its inclusion in the List of Invasive Alien Species of Union concern. The existing studies have systematically examined the plant's morphology, habitat requirements, ecology, life cycle, and genetic aspects, emphasizing the traits associated with its high invasive potential. The species exhibits a preference for moist to wet and nutrient-rich soils, commonly found in river valleys and associated riparian habitats. Our research, based on samples collected from Romania, aims to identify and detail the structural features of the vegetative body of Impatiens glandulifera that contribute to its adaptive ability to specific environmental conditions. The anatomical investigations revealed a secondary root and stem structure, enhancing this annual species' robustness and resistance in plant communities. [ABSTRACT FROM AUTHOR]

Invasive alien plants (weeds) are a growing, worldwide problem. Importation ('classical') biological control, using exotic insects, may be a key component in controlling invasive plants. Two‐thirds of plant species targeted worldwide by biocontrol programs experience some level of control, but the success rates are geographically variable and still hard to predict. Better understanding of the interactions of the species involved, and the effects of changing climate, may help to further improve both the efficacy and the predictability of this method. This requires pre‐release studies, as well as post‐release studies that quantify the impact at the population level to validate methodologies and assumptions of pre‐release studies. The 12 original papers of this special issue include pre‐ and post‐release studies on 13 insect species from five orders. The studies cover a wide range of methodologies and altogether they highlight that both target and non‐target impact are highly context dependent. This dedicated issue includes directions for methodological improvements to better assess ecological host ranges of agents and to avoid rejection of safe agents. [ABSTRACT FROM AUTHOR]

An updated inventory of the invasive flora of Bosnia and Herzegovina is presented. The checklist includes 66 taxa (63 species, one subspecies and two hybrids), distributed between 46 genera and 28 families. The most common family is Compositae (20 taxa; 30.30%) and the most diverse genera are Amaranthus (five taxa) and Erigeron, with four taxa. The predominant life forms are therophytes (54.54%) and hemicryptophytes (22.73%). Most invasive alien plant species are native in the Americas (46) and Asia (14). Most taxa in the invasive alien flora of Bosnia and Herzegovina (43 taxa, 65.15%) have been introduced accidentally, 19 taxa (28.79%) have been introduced deliberately, whereas the remaining four taxa (6.06%) have been introduced in both ways: deliberately and accidentally. Five invasive alien taxa of concern to the European Union have been recorded in Bosnia and Herzegovina. [ABSTRACT FROM AUTHOR]

Background: This study conducted a survey for establishing in-situ and ex-situ conservation measures for northern lineage plants that are vulnerable to climate change and for designating Forest Genetic Resource Reserve for 25 algific talus slope sites, which are specific areas of forest biodiversity. The survey was conducted in South Korea within a distance of 50 m to the east, west, north and south from the core area where wind blows to the algific talus slopes. The study was conducted once or twice per season from April 2016 to November 2021. New information:Vascular plants of 25 algific talus slope sites in South Korea included a total of 1,052 taxa of 125 families, 486 genera, 947 species, 23 subspecies, 75 variety and 7 forma. The maximum surveyed area was 0.09 km, accounting for only 0.00014% of the 62,860 km forest area in Korea, but comprise 22.27% of the 4,724 species of vascular plants in Korea. The algific talus slopes are areas rich in forest biodiversity. Six taxa were categorized as endangered, including Paeonia obovata Maxim. Sixty-seven taxa, including Astilboides tabularis (Hemsl.) Engl.; 58 taxa endemic to the Korean Peninsula, including Weigela subsessilis (Nakai) L.H. Bailey; and 317 taxa of floristic target plants were categorized as rare plants in the Red list. Further, 181 taxa were identified as northern lineage plants and 32 taxa, including Sillaphyton podagraria (H. Boissieu) Pimenov, were limestone area plants. Regarding alien plants, 75 taxa, including Oenothera biennis L., were identified and the naturalization and urbanization rates were 7.13% and 12.12%, respectively. Plants specific to the phytogeography of the 25 algific talus slope sites in this study were Vaccinium vitis-idaea L., Rosa koreana Kom., Syringa villosa Vahl subsp. wolfii (C.K. Schneid.) Jin Y.Chen & D.Y. Hong, Lonicera chrysantha Turcz. ex Ledeb., Tephroseris flammea (Turcz. ex DC.) Holub, among others. [ABSTRACT FROM AUTHOR]

Knowledge of the weed flora of a certain area, as well as knowledge of the relationship between cultivated plants and weed plants, is important for successful weed control and the efficient application of agrotechnical measures. The aim of this paper is to provide an overview of the weed flora in maize fields in the area of Novi Grad, as well as a taxonomic analysis, an analysis of the biological spectrum, a phytogeographical analysis and an analysis of ecological indicators of the maize weed flora. During field research on two maize fields in the area of Donji Rakani village (Novi Grad), a total of 38 species of vascular plants were collected, which were systematized into 35 genera and 16 families. The most abundant in terms of species numbers were the families Compositae (31.58%) and Poaceae (18.42%), as well as the genera Erigeron, Ranunculus and Setaria. Hemicryptophytes (36.84%) and therophytes (31.58%) dominated the biological spectrum. Phytogeographical analysis revealed the dominance of the Eurasian (25.81%) floral element. A total of seven adventive species were recorded. The paper also presents the results of the analysis of ecological indicators for soil moisture, soil reaction, nutrients, light and temperature. The results of our research contribute to a better knowledge of the weed flora in maize fields, which could be useful for creating more efficient weed control measures.

Abstract It is presented the first taxonomic study of the tribe Coreopsideae (Asteraceae) in Northeastern Brazil. A total of seven genera and 16 species were recorded in the region, with Bidens being the richest genus (8 spp.). Bidens tenera and Cosmos bipinnatus were recorded for the first time to the region, and Heterosperma ovatifolium represents the first record to Brazil. Bidens, Chrysanthellum, and Dahlia are taxonomically problematic that is reflected by several misidentifications found in the herbaria collections. Coreopsis, Cosmos, and Dahlia species are cultivated as ornamental but are scarcely represented in the herbaria. This study provides a checklist, an identification key to all species, in addition to discussing the importance of studying alien species for a better understanding of the Brazilian flora.

Background. Land use change is a key catalyst of global biodiversity loss and ecosystem degradation. Deforestation and conversion of natural habitats to agricultural or urban areas can profoundly disrupt plant-flower visitor interactions by altering their abundances and distribution. Yet, specific studies analyzing the effects of land use change on the structure of networks of the interactions between particular groups of flower visitors and their plants are still scarce. Here, we aimed to analyze how converting native habitats affects the species composition of butterfly communities and their plants, and whether this, in turn, leads to changes in the structure of interaction networks in the modified habitats. Methods. We performed bi-monthly censuses for a year to record plant-butterfly interactions and assess species diversity across three habitat types, reflecting a land-use change gradient. From original native juniper forest to urban and agricultural zones in central Mexico, one site per land use type was surveyed. Interactions were summarized in matrices on which we calculated network descriptors: connectance, nestedness and modularity. Results. We found highest butterfly diversity in native forest, with the most unique species (i.e., species not shared with the other two sites). Agricultural and urban sites had similar diversity, yet the urban site featured more unique species. The plant species richness was highest in the urban site, and the native forest site had the lowest plant species richness, with most of the plants being unique to this site. Butterfly and plant compositions contrasted most between native forest and modified sites. Network analysis showed differences between sites in the mean number of links and interactions. The urban network surpassed agriculture and native forest networks in links, while the native forest network had more interactions than the agriculture and urban networks. Native plants had more interactions than alien species. All networks exhibited low connectance and significant nestedness and modularity, with the urban network featuring the most modules (i.e., 10 modules). Conclusions. Converting native habitats to urban or agricultural areas reshapes species composition, diversity and interaction network structure for butterfly communities and plants. The urban network showed more links and modules, suggesting intricate urban ecosystems due to diverse species, enhanced resources, and ecological niches encouraging interactions and coexistence. These findings emphasize the impacts of land use change on plant-butterfly interactions and the structure of their interaction networks. [ABSTRACT FROM AUTHOR]

Crataegus species (Rosaceae) or hawthorns form dense thickets and displace native vegetation out of their native range. In South Africa, Crataegus monogyna and C. mexicana are under surveillance but there is lack of information on their pollination ecology. Therefore, this study sought to investigate the pollination mechanism and potential insect pollinators of these plants. Pollinator exclusion experiments were conducted on ten plants each of C. monogyna and C. mexicana near the towns of Hogsback and Seymour respectively, in the Eastern Cape Province. Flowers of each of these species were also observed to determine the diversity and distribution of insect visitors throughout the day (i.e. morning, mid day and afternoon). The results showed that C. monogyna and C. mexicana are capable of self and cross-pollination. Fruit set from open inflorescences of C. monogyna was 40.88 ± 0.08%, significantly higher than bagged inflorences. Fruit set from open inflorescences of C. mexicana was 48.18 ± 0.03%, significantly higher than those of bagged inflorescences. Hymenopterans were the most frequent visitors on C. monogyna flowers while dipterans were the most frequent visitors on C. mexicana flowers. The distribution of insects did not vary with the time of day for each plant species. Insect pollination, therefore, plays a significant role in the fruiting of C. monogyna and C. mexicana in the Eastern Cape. The results of this study contribute to the understanding of the ecology and phenology of Crataegus species in South Africa and thus the evaluation of their invasive status. [ABSTRACT FROM AUTHOR]

Soil microbes can profoundly affect species coexistence and alien plant invasion via plant–soil feedbacks (PSFs). Theoretically, plants can modify soil biotic communities (e.g. fungal and bacterial communities) sequentially via rhizo‐inputs in the growing season and via litter decomposition in the non‐growing season, and in this way affect the performance of plant individuals that establish in the same soil in the following growing season. However, how plants affect soil microbes via sequential rhizosphere and litter inputs and how these soil microbial legacies feedback to subsequent plants remains unclear.Here, we first explored the sequential effects of living individuals and their leaf litter on soil fungal communities, using 42 common alien and native species in China, and then estimated their PSF effects on three common test species.Our results show that living plants growing in field soil developed distinct rhizosphere fungal communities within one season. After the removal of conditioning plants, the fungal communities in these conditioned soils changed more dramatically in the absence than in the presence of leaf litter, suggesting that leaf litter inputs prolonged the species‐specific legacies that conspecific living individuals exerted in the soil. Moreover, leaf litter induced general negative effects on all test species in the second growing season. Conditioning plant origin (native vs. alien) and life cycle (annual vs. perennial), respectively, had a slight or no impact on fungal community composition, and conditioning plant origin did not affect PSF responses of the test species.Synthesis: These findings show that leaf litter prolongs soil fungal legacies of conspecific living individuals, which can lead to carryover effects on heterospecific plant growth in the next season. Our findings highlight the importance of leaf litter for plant–soil interactions and thereby stress the potential importance of plant litter as a driver of plant community dynamics. [ABSTRACT FROM AUTHOR]

This paper specifies the invasibility of common plant community types in the natural habitats of the Middle Urals. Invasibility was defined as the vulnerability of a community to alien plant species invasions, regardless of the conditions in which the community existed. We analyzed 749 vegetation relevés made in natural bogs, floodplains, rocky grasslands, meadows, and forest communities. We surveyed urban and non-urban habitats (30–40 km from the city). Invasibility was calculated in two different ways based on two parameters: the number and proportion of alien species in the relevé. These invasibility parameters are widely applicable and comparable, scale-independent, measurable, and reliable, based on data that do not require the destruction of ecosystems or biota and are based on available data. Based on the invasibility degree, we identified three community-type groups with two subgroups in one group. In ascending order of invasibility degree, the community types were arranged as follows: (1) bogs with and without trees; (2a) coniferous forests; grass communities in floodplains; (2b) deciduous forests, coniferous plantations, floodplain communities with woody plants; and (3) dry meadows and rocky grasslands. Obtained results of the assessment of different plant community invasibility may be used to understand patterns of alien plant distribution in local habitats and the reasons for the different vulnerability of communities to plant invasions. [ABSTRACT FROM AUTHOR]

The adventive fraction of the flora of Seymskiy Regional Landscape Park (Sumy Oblast, Ukraine) including 237 species of 183 genera and 62 families, is described. Its systematic and biomorphological structures was analyzed. The major families, namely Asteraceae, Poaceae, Brassicaceae, Fabaceae, Rosaceae, Lamiaceae, Boraginaceae, Chenopodiaceae, Solanaceae and Malvaceae are represented by 152 species (64.1% of the alien fraction). Therophytes (49.4%), hemicryptophytes (28.7%) and phanerophytes (17.7%) were found to be the prevailing life forms in the alien flora of the park. According to the time of immigration, kenophytes (69%) predominate among alien species of the park. The most common species belonged to the group native of North America (23.2%), the Mediterranean (21%), Asian (17.7%) and Mediterranean-Iran-Turanian (11.4%). Xenophytes (54.4%) predominated by way of penetration into the territory, ergasiophytes were represented by 39.6% and xeno-ergasiophytes by 5.9% of the species. According to the degree of naturalization epoecophytes (30%) and agrio-epoecophytes (27.8%) had high ranked positions as part of the alien flora and there are slightly less ephemerophytes (14.8%), colonophytes (14.3%), agriophytes (6.8%) and ergasiophygophytes (6.3%). At the time of the survey, we considered 162 species as naturalized, 50 taxa as casuals, 16 species as potentially invasive, and 9 as those of invasive status. The obtained data indicated the need for action to stop the increase in the adventive species within the park's flora in order to reduce their negative impact on natural habitats and the native flora.

Background Land use change is a key catalyst of global biodiversity loss and ecosystem degradation. Deforestation and conversion of natural habitats to agricultural or urban areas can profoundly disrupt plant-flower visitor interactions by altering their abundances and distribution. Yet, specific studies analyzing the effects of land use change on the structure of networks of the interactions between particular groups of flower visitors and their plants are still scarce. Here, we aimed to analyze how converting native habitats affects the species composition of butterfly communities and their plants, and whether this, in turn, leads to changes in the structure of interaction networks in the modified habitats. Methods We performed bi-monthly censuses for a year to record plant-butterfly interactions and assess species diversity across three habitat types, reflecting a land-use change gradient. From original native juniper forest to urban and agricultural zones in central Mexico, one site per land use type was surveyed. Interactions were summarized in matrices on which we calculated network descriptors: connectance, nestedness and modularity. Results We found highest butterfly diversity in native forest, with the most unique species (i.e., species not shared with the other two sites). Agricultural and urban sites had similar diversity, yet the urban site featured more unique species. The plant species richness was highest in the urban site, and the native forest site had the lowest plant species richness, with most of the plants being unique to this site. Butterfly and plant compositions contrasted most between native forest and modified sites. Network analysis showed differences between sites in the mean number of links and interactions. The urban network surpassed agriculture and native forest networks in links, while the native forest network had more interactions than the agriculture and urban networks. Native plants had more interactions than alien species. All networks exhibited low connectance and significant nestedness and modularity, with the urban network featuring the most modules (i.e., 10 modules). Conclusions Converting native habitats to urban or agricultural areas reshapes species composition, diversity and interaction network structure for butterfly communities and plants. The urban network showed more links and modules, suggesting intricate urban ecosystems due to diverse species, enhanced resources, and ecological niches encouraging interactions and coexistence. These findings emphasize the impacts of land use change on plant-butterfly interactions and the structure of their interaction networks.

The plant species Erechtites hieraciifolius (Asteraceae) is here reported for the first time in Italy as a naturalized neophyte in the Classical Karst. The species was observed in 2023 in post-fire forest areas burnt by wildfires in the summer 2022. The features of findings suggest for a naturalization of the species with putative invasive character. This novel occurrence highlights the need for additional research to better understand its colonization and expansion, suggesting the need of early eradication actions.

The purpose of the study was to estimate invasion levels of alien plants in various natural and anthropogenic habitats of the Middle Urals in two urbanization manifestation variants: (1) within the boundaries of a large city; and (2) in suburban areas. In total, 965 geobotanical relevés produced in natural (bogs, floodplains, petrophytic areas, meadows, and forests) and anthropogenic (wastelands, public gardens, and residential areas) habitats were analyzed. Natural habitats were surveyed within the boundaries of a large city and in its suburban zone (at distances of 30–40 km from the city). Invasion levels were determined based on the number and proportion of alien (adventitious) species in the description. Both in suburban and urban conditions, the lowest numbers of alien species were recorded in bog habitats (on average, 0–0.6 species per description); while the largest numbers, in anthropogenic habitats (on average, 9.8–17.6 species per description). Outside the city, average numbers of alien species in natural habitats (except for bogs) varied in the range of 1.0–2.8 species per description; within the city, 3.8–6.2 species per description. In natural habitats (except for bogs), average shares of alien species varied in the range of 1.8–5.6% outside the city and in the range of 8.1–16.2% within the city; in anthropogenic habitats, they varied in the range of 22.8–32.8%. Suburban and urban wastelands did not differ in numbers and proportions of alien species (10.3 and 12.9 species per description and 25.3 and 30.2%, respectively). Invasion levels identified in suburban areas are consistent with those recorded in Europe. [ABSTRACT FROM AUTHOR]

Both urban and rural environments around the globe have become dominated by alien plant species to the extent that plantscapes from one region or country have become difficult to distinguish from many others. This process of plant community homogenisation comes at a cost to cultural identity and undermines people's sense of place. Although invasive alien plant species have received considerable attention in recent decades, issues with non‐invasive alien plant species have largely been ignored, and yet they contribute significantly to biotic homogeneity and impose an ever accumulating invasion debt: a debt that increases in proportion with their population sizes. By contrast, an abundance of native species in the places where people live is important for strengthening commitment to biodiversity conservation. Is there therefore sufficient evidence of harm from increasing numbers of non‐invasive alien plants to justify local and central governments introducing measures to substantially reduce the proportion of non‐invasive aliens in both urban and rural environments? [ABSTRACT FROM AUTHOR]

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Human-assisted introduction of alien plants is causing ecosystem transformations worldwide and is considered an important threat to biodiversity. We provide a European assessment of habitat levels of invasion in heathlands and scrub and identify successful alien plants and invasion trends across biogeographical regions. We analysed a geographically stratified data set of 24,220 dwarf shrub and scrub vegetation plots sampled across Europe. Among the 6547 vascular plant taxa occurring in these plots, we identified 311 neophytes (4.8%, i.e. alien species introduced in Europe or its sub-regions after 1500 AD) and compared five metrics of the level of invasion in (i) EUNIS habitats, (ii) broad habitat groups and (iii) biogeographical regions of Europe. We related habitat-specific levels of invasion to elevation and climatic variables using generalized linear models. Among neophytes, phanerophytes of non-European origin prevailed. The most frequent neophytes in the plots were Prunus serotina, Robinia pseudoacacia and Quercus rubra among phanerophytes, Impatiens parviflora among therophytes, and Erigeron canadensis and Solidago gigantea among hemicryptophytes. Levels of invasion significantly differed among habitats and biogeographical regions. The most invaded habitat was Macaronesian lowland scrub, followed by riparian scrub, Rubus scrub and forest-clearing scrub of temperate Europe, and coastal dune scrub of the Atlantic region. The levels of invasion were low in the shrublands of the Arctic and Mediterranean regions and decreased with elevation within habitats. Results suggest that insularity, low elevation, frequent disturbances, and high availability or considerable fluctuation of resources promote neophyte invasions in European shrublands. [ABSTRACT FROM AUTHOR]

The assumption that climatic growing requirements of invasive species are conserved between their native and non-native environment is a key ecological issue in the evaluation of invasion risk. We conducted a growth chamber experiment to compare the effect of water regime and temperature on the growth and mortality of native and invasive populations of common gorse seedlings (Ulex europaeus L.). Seeds were sampled from 20 populations of five areas from both native (continental France and Spain) and non-native areas (New Zealand, Canary and Reunion islands). The seedlings were grown over 36 days in two temperature treatments (ambient and elevated) combined with two water treatments (irrigated or droughted). The elevated temperature (ET) was defined as the highest temperature observed at the niche margin in the different countries. While ET increased seedlings growth, the drought treatment increased mortality rate and limited seedlings growth. Under ET and drought, native populations showed a greater mortality rate (53%) than invasive populations (16%). Invasive seedlings also showed higher above- and belowground development than native ones under these constrained climatic conditions. While phenotypic plasticity did not differ between native and invasive populations, the difference between populations in terms of total dry mass could be related to differences in the climate of origin (precipitation in particular). Assessing the importance of phenotypic changes between populations within invasive species is crucial to identify the margins of their climatic distribution range and to highlight areas where management efforts should be concentrated in order to limit its spread. [ABSTRACT FROM AUTHOR]

The general shape (from linear to complex curve), direction (negative and positive) and strength (steepness of the slope) of abundance–impact relationships for different impact metrics are poorly known, despite their importance in understanding and predicting ecological repercussions of invasive species. It is also an open question how the functional traits of invasive species may influence the abundance–impact relationship.We studied 11 widespread herbaceous invasive alien species of East‐Central Europe and their 16 impact metrics (resident plant communities' ecological characteristics, trait composition, functional diversity and soil parameters) by sampling invaded and similar, uninvaded sites (space‐for‐time substitution method). Our aim was to (1) investigate the detailed ecological impacts of invasive plants on native plant communities; (2) explore the type of cover–impact relationships across impact metrics and their consistency across species and (3) study whether the cover–impact relationship depends on functional traits of invasive species.When considering all invasive species together, we found that invaded plant communities were less species rich and less functionally even but showed higher values of Rao's Q diversity index, and higher nitrogen, phosphorus and organic carbon soil nutrient content compared to uninvaded communities. However, the species‐wise analyses revealed strikingly different impacts among the 11 invasive species and also among impact metrics.Regarding the type of cover–impact relationships, we found no consistencies across invasive species and impact metrics. Still, nonlinear relationships prevailed when species were analysed together and linear relationships when species were studied individually. The functional traits of the invasive species explained only a small part of this response heterogeneity; mostly, the small‐seeded perennial invasive species affected the cover–species richness relationship.Synthesis: Herbaceous invasive plant species have a cover‐dependent impact on resident plant communities, but there are no consistent patterns across impact metrics and invasive species. Specific traits or trait syndrome of invasive species may affect the heterogeneity of cover–impact relationships, but that would need further study. We highlighted the importance of impact assessments involving invasive species' abundance to unmask cryptic impacts for species that show contrasting effects along an abundance gradient. [ABSTRACT FROM AUTHOR]

This paper presents the main directions and range of man-made changes to the vascular flora and their effects at the vegetation level. The native flora of Poland, located in the temperate zone of Central Europe, comprises approximately 2639 species. The effect of human pressure, which began in the Neolithic and has intensified in the last 200 years, has caused changes in the native flora and has included an inflow of 975 alien species, 560 of which have become permanently established. Currently, at least 704 native species are recognized as endangered, and only 623 are recognized as being able to occupy habitats that were created or strongly transformed by humans. Native species (apophytes) and aliens (anthropophytes) have co-created completely new plant communities in these habitats. Among the alien plants, neophytes (399 species) outnumber archaeophytes (161 species). Additionally, many neophytes (123 species) can penetrate seminatural and natural communities. Research has shown that the proportions of apophytes, alien plants, and declining species can be used to clearly differentiate plant communities and be used as an indicator of anthropogenic changes. A comparison of the man-made changes in Polish flora and vegetation in other countries showed that the changes in Poland are part of the global process of environmental degradation and are aggravated by the country's economic development. [ABSTRACT FROM AUTHOR]

As a result of a floristic survey carried out in riparian ecosystems of the south-eastern part of the Iberian Peninsula (Spain), the first report of well-established populations of the alien cultivated plant species Cucurbita moschata Duchesne for the Iberian Peninsula is provided here. Data about the morphological description (compared to other Cucurbita species), certain clarification aspects about the typification status of this name and related synonyms, and the ecological and climatic conditions of the riparian area are given together with an identification key of the Cucurbita species to facilitate further identification. The alien status and distribution of C. moschata together with its relatives C. ficifolia, C. pepo and C. maxima are reviewed for the Spanish references. This study outlines the first record of a naturalized population of C. moschata in Spain, well supported by the stability of the population over the years and in the ecological conditions. Finally, detailed ecological data indicate that agricultural activities together with riparian habitatsare starting points and corridors, respectively, for seed dispersal for the process of the invasion of alien plants in the south-eastern Iberian Peninsula. [ABSTRACT FROM AUTHOR]

Huge economic costs and ecological impacts of invasive alien species (IAS) in the protected areas (PAs) worldwide make their timely prediction and potential risk assessment of central importance for effective management. While the preborder weed risk assessment framework has been extensively evaluated and implemented, the postborder species risk assessment framework has not been subjected to the same degree of scrutiny. Here we used a rather more realistic modified version of the Australian Weed Risk framework (AWRM) for Dachigam National Park (DNP) in Kashmir Himalaya against 84 plant species, including 55 alien species and 29 fast spreading native species, for risk analysis. We found two very high‐risk species, three high‐risk species, 10 medium‐risk species, 29 low‐risk species, and 40 negligible‐risk species in the DNP. The containment scores accordingly ranged from 14.4 to 293.5 comprising of 27 species that can be contained with very high feasibility, 23 species with high feasibility, 14 species with medium feasibility, and 12 species which cannot be contained easily thereby having low feasibility of containment (FOC) score. However, eight species which have a negligible FOC score are difficult to contain within their infestation sites. Our results demonstrate the merit of the AWRM with a caution that the necessary region‐specific modifications may help in its better implementation. Overall, these results provide quite a promising tool in the hands of protected area managers to timely and effectively deal with the problem of plant invasions. [ABSTRACT FROM AUTHOR]

This paper examines the naturalization of alien plants cultivated at the Caucasian flora exhibition in the Main Botanical Garden of the Russian Academy of Sciences in Moscow. Naturalized and nonnaturalized species were compared to identify traits contributing to a potentially successful invasion. Over the period of 76 years, 1246 taxa were intentionally introduced; of them, 57 species (4.5%) have successfully naturalized, while 12 species (less than 1%) have actually "escaped" beyond the boundaries of the exhibition. Poor maintenance of the plant collection in the 1990s facilitated the spread of resistant unpretentious plants. A revision performed in 2020 showed that 17 more species have entered the naturalization phase. Species of the families Apiaceae and Boraginaceae demonstrate the highest degrees of naturalization. Natural regeneration was recorded for 440 species. The greatest number of naturalized taxa (19%) are represented by plants propagating both vegetatively and by self-seeding. Of species propagating only by self-seeding, 16% have naturalized; of those propagating only vegetatively, only 6%. Representatives of subalpine tall grasses and forest communities of the Caucasus adapted to the conditions of Moscow to the greatest extent. None of species confined to semideserts, arid sparse forests, upland xerophytic communities, steppes, alpine meadows, high-altitude rocks and screes, and subtropical forests of Colchis and Talysh became invasive. Short-rhizome and long-rhizome perennial herbaceous plants prevail among the naturalized species. The common opinion that the introduction of endemic plants is a difficult process was not confirmed. Endemic plants are insignificantly inferior to plants with wide distribution ranges in terms of the proportion of naturalized species, but surpass them in terms of the numbers of highly invasive and invasive species. A set of traits indicating with a high probability that an intentionally introduced plant species can transform into an invader was identified. The invasiveness of Caucasian species was analyzed; the results of analysis will be used to prevent the introduction of aggressive alien plants and develop a scientifically based approach to exhibition of plants. [ABSTRACT FROM AUTHOR]

Understanding the large-scale distribution patterns of invasive alien plants can not only identify potential high-risk areas but also provide key information for developing management strategies to mitigate plant invasion. Here, for the first time, we mapped the spatial distribution of 239 invasive plant species in China at much finer spatial resolution (50 × 50 km2). We also developed a new metric, invasion level score (ILS), which represent both invasive plant richness and the number of high-risk invasive plants per grid cell, to identify hotspots of plant invasion. Finally, we compared differences in invasive plant richness and ILS between protected and non-protected areas. We found that the counties and grids in the southern and eastern coastal regions of China have the highest species richness and ILS. The richness and ILS decrease from southeast to northwest China. Meanwhile, the high-risk areas for invasion level are concentrated in and around provincial capitals in the southern, eastern, and northern China. We also found that protected areas in China have significantly more invasive plants and higher ILS than non-protected areas. The grid cells with high invasive plant richness and ILS are mostly distributed in regions with high population density, likely due to urban effect. The need to direct management attention towards the southern and eastern China and particularly within protected areas was suggested by our findings. Our study provides a comprehensive assessment of the distribution and risk of invasive plants in China, as well as a scientific foundation for further advancing the prevention and management of invasive plants.

Acmella radicans (Jacquin) R.K. Jansen is a new invasive species recorded in Yunnan Province, China, and little is known about its allelopathic potential and allelochemicals. In this study, the allelopathic effects of the essential oil (EO) of A. radicans on seed germination and seedling growth of four common plants, Brassica napus, Brassica rapa ssp. chinensis, Digitaria sanguinalis, and Lolium multiflorum, were explored. The results showed that the seed germination index, germination rate, root length, stem length, and biomass of B. napus and B. rapa ssp. chinensis were significantly inhibited at all EO concentrations of A. radicans, but there was a ‘low-promotion and high-inhibition effect’ on the root length of D. sanguinalis and L. multiflorum at low concentrations of 0.5 μL·mL−1 and 0.5–1.0 μL·mL−1, respectively. With increasing concentrations of EO, the inhibition rates of seed germination and seedling growth of four common plants gradually increased, and D. sanguinalis and L. multiflorum were the most inhibited, followed by B. rapa ssp. chinensis, and the least inhibited was B. napus. Thirty-two components were identified using GC–MS, representing 99.07% of the EO in A. radicans. The major components were 2-tridecanone (30.46%), caryophyllene oxide (19.18%), 4,8,11,11-tetramethylbicyclo[7.2.0]undec-3-en-5-ol (7.84%), β-caryophyllene (7.67%), and widdrol (4.7%). Among the compounds we identified, (E,E)-2,4-decadienal, 2-tridecanone, γ-cadinene, δ-cadinene, (E)-α-cadinol, spathulenol, caryophyllene oxide, and widdrol have been previously reported as having possible allelopathic effects. Our study was the first to show that A. radicans could potentially release allelochemicals to influence neighboring plants during its invasion and expansion.

The composition and structure of soil seed banks provide insight into the long-term implications of plant invasions on resident communities. The effect of Salpichroa origanifolia (Sa) on the seed bank of a coastal mesophile forest (Tuscany) was studied by growing Sa-rhizomes in soils from low and high invaded sites, in full sun and canopy shade. Sa growth patterns, and the composition, biomass, nitrogen, and phosphorus contents of seedlings which emerged from seed banks were determined. Seed bank abundance and richness were also determined from under and 2 m apart established Sa populations. Sa plants’ leaf traits and biomass allocation changed in response to light conditions. The germination of seed bank seedlings was not affected or even promoted by Sa, while their biomass as well as N and P uptake were more than halved in both light conditions, leading to a progressive depletion of the forest seed bank. Richness was lower under established Sa populations. Sa seedlings exerted a greater suppression on residents than Sa adults, and these appeared more competitive against their own seedlings than on residents. Sa is an invader of concern for Mediterranean forests because of its adaptability to shaded conditions, the competitiveness of its seedlings, and its vegetative spread by means of rhizomes.

iNaturalist defines itself as an “online social network of people sharing biodiversity information to help each other learn about nature” and it is likely one of the largest citizen science web portals in the world, as every year millions of observations across thousands of species are gathered and collectively compiled by an engaged community of nearly 3 million users (November 2023). The strengths and potentialities that explain the success of the platform are reviewed and include, among others, its usability and low technical requirements, immediacy, open-access, the possibility of interacting with other users, artificial-intelligence-aided identification, versatility and automatic incorporation of the validated records to GBIF. iNaturalist has, however, features that scientists need to carefully consider when using it for their research, making sure that the quality of observations does not limit or hinder its usefulness in plant research. While these are identified (e.g., the lack of representative photographs for many observations or the relatively frequent identification errors), we provide some suggestions to overcome them and, by doing so, improve the use and add value to iNaturalist for plant research.

Exotic invasive plants are present in almost all terrestrial ecosystems. Their spread and ability to colonize new habitats are predicted to increase with human travel, global trade, and climate change. These plants alter the environments they invade in multiple ways, affecting surrounding species. Chemically, invasive plants can modify their environment by releasing secondary metabolites such as root exudates (liquid) or airborne (gaseous) volatile organic compounds (VOCs). The allelopathic effect of invasive species' root exudates is well studied and acknowledged as a trait contributing to invasiveness. However, less is known about the effects of invasive species' VOCs, which are likely to play important ecological roles. Therefore, we conducted a systematic review of the literature during the last decade (2012–2022) to explore what is known about the ecological aspects of VOCs emitted by invasive plants, focusing on the factors affecting their emission (genetic, biotic, and abiotic), and their role on plant-plant and plant-insect interactions. We found 29 studies matching our search criteria. These studies suggest that invasive species are more “chemically diverse” than their native counterparts and have different chemical behavior in native compared to invaded ranges. The studies further highlight that chemical traits are heritable and contribute to invasiveness. Multiple biotic and abiotic factors affecting invasive plants' VOC emission have been explored (e.g., herbivory, soil microorganisms, warming, and CO2). The studies indicate that invasive plants may experience less variation in their VOC emissions in response to environmental change than natives, with trade-offs between growth, reproduction and defense influencing VOC emissions. Regarding the impact on native species and their interactions, the allelopathic role of invasive plants' VOCs on native plants is well documented, consistently showing phytotoxic effects. There is also evidence of their involvement in neighbor detection. While volatile-mediated interactions between invasive plants and native insects remain poorly studied, the existing evidence shows that invasive plant VOCs have the potential to disrupt communication between native plants and insects. But insects also use multiple cues to make foraging/oviposition decisions, compensating for the disruptive effect of invasive plant VOCs. To conclude, we identify knowledge gaps and propose avenues for future research.

Movements of organisms through distinct places can change the dynamics of ecological interactions and make the habitat conducive to the spread of diseases. Faced with a cyclical scenario of invasions and threats in a One Health context, we conducted a scientometric study to understand how disturbances in environments with invaded vegetation affect the incidence of parasites and disease prevalence rates. The search was carried out in Web of Science and Scopus databases, with keywords delimited by Boolean operators and based on the PRISMA protocol. Thirty-sixarticles were full-read to clarify the interaction between diseases and invaded areas. The analysis covered publications from 2005 to 2022, with a considerable increase in the last ten years and a significant participation of the USA on the world stage. Trends were found in scientific activities, and we explored how invasive species can indirectly damage health, as higher concentrations of pathogens, vectors, and hosts were related to structurally altered communities. This paper reveals invaded plants threats that enhance disease transmission risks. It is likely that, with frequent growth in the number of introduced species worldwide due to environmental disturbances and human interventions, the negative implications will be intensified in the coming years. [ABSTRACT FROM AUTHOR]