Search Results (792)

Acacia mearnsii De Wild. has been introduced to over 150 countries for its economic value. However, it easily escapes from plantations and establishes monospecific stands across plains, hills, valleys, and riparian habitats, including protected areas such as national parks and forest reserves. Due to its negative ecological impact, A. mearnsii has been listed among the world’s 100 worst invasive alien species. This species exhibits rapid stem growth in its sapling stage and reaches reproductive maturity early. It produces a large quantity of long-lived seeds, establishing a substantial seed bank. A. mearnsii can grow in different environmental conditions and tolerates various adverse conditions, such as low temperatures and drought. Its invasive populations are unlikely to be seriously damaged by herbivores and pathogens. Additionally, A. mearnsii exhibits allelopathic activity, though its ecological significance remains unclear. These characteristics of A. mearnsii may contribute to its expansion in introduced ranges. The presence of A. mearnsii affects abiotic processes in ecosystems by reducing water availability, increasing the risk of soil erosion and flooding, altering soil chemical composition, and obstructing solar light irradiation. The invasion negatively affects biotic processes as well, reducing the diversity and abundance of native plants and arthropods, including protective species. Eradicating invasive populations of A. mearnsii requires an integrated, long-term management approach based on an understanding of its invasive mechanisms. Early detection of invasive populations and the promotion of public awareness about their impact are also important. More attention must be given to its invasive traits because it easily escapes from cultivation. Full article

The invasion of alien species has emerged as a global ecological challenge and invasive species can seriously threaten the habitats of native plants and intensify interspecific competition, ultimately exerting significant impacts on local ecosystems. Therefore, it is necessary to implement effective prevention and control strategies to reduce these impacts and maintain ecological stability. Against this backdrop, it is especially critical to analyze the influencing factors of invasive alien species and predict their future trends. Given China’s vast territory, complex natural geography, and diverse climatic conditions, the problem of invasive alien species in China is particularly severe, and scientific countermeasures are urgently required. Up to now, the number of invasive alien plant species in China has exceeded 520. Based on the number of invasive plant species in each province of China, this study analyzes the intrinsic connection between various influencing factors and invasive species, and through correlation analysis identifies the influencing factors, which are then used to analyze and predict the future invasion risks that each region may face. Full article

Islands subjected to anthropogenic disturbance are highly susceptible to alien plant invasions. However, the alien floral diversity of China’s islands has been insufficiently studied, hindering its control. Weizhou Island (northern South China Sea) has experienced long-term human exploitation. We inventorized its alien, naturalized, and invasive vascular plants (based on herbarium specimen data for 2018–2024 and surveys of 112 plots); analyzed species composition, origins, life forms, and habitats; and conducted an invasive species risk assessment. This identified 203 aliens, including infraspecific and hybrid taxa, 129 (63.5%) naturalized and 71 (55.0% of the naturalized species) invasive. The aliens were dominated by the Fabaceae, Asteraceae, and Euphorbiaceae, particularly genera such as Euphorbia, Senna, and Portulaca, originating primarily in North America, Oceania, and Africa. Perennial herbs were the most common lifeform, followed by annual herbs and shrubs. Invasion hotspots were primarily abandoned farmland, roadsides, and agricultural lands. Using the Analytic Hierarchy Process, we classified the 71 invasive species as representing high-risk, moderate-risk, and low-risk (20, 16, and 35 species, respectively). Bidens pilosa, Ageratum conyzoides, Opuntia dillenii, and Leucaena leucocephala pose severe threats to the island ecosystem. This first complete inventory of the alien flora on Weizhou Island offers critical insight into the management of invasive alien plants in island ecosystems. Full article

Integrating nature-based solutions into sustainable urban design has become increasingly important in response to rapid urbanization and climate-related environmental challenges. As part of these solutions, green walls not only enhance the thermal and acoustic performance of buildings but also contribute to urban ecosystem health by supporting biodiversity. In this context, the careful selection of plant species is essential to ensure ecological efficiency, resilience, and low maintenance. This study presents a model for selecting plant species suitable for natural green walls in Mediterranean cities, with a focus on habitats protected under Directive 92/43/EEC. The selection followed a multi-phase process applied to the native flora of Italy, using criteria such as chorological type, life form, ecological indicator values, altitudinal range, and habitat type. Alien and invasive species were excluded, favoring only native Mediterranean species adapted to local pedoclimatic conditions and capable of providing ecosystem, esthetic, and functional benefits. The outcome of this rigorous screening led to the identification of a pool of species suitable for green wall systems in Mediterranean urban settings. These selections offer a practical contribution to mitigating the urban heat island effect, improving air quality, and enhancing biodiversity, thus providing a valuable tool for designing more sustainable and climate-adaptive buildings. Full article

Faxonius limosus is an invasive alien crayfish species that has a negative effect on aquatic biodiversity. Using its meat as food could help reduce its ecological impact while providing a protein source. In order to do that, the initial step was to determine safety and nutritional parameters of crayfish meat. Samples from two localities were analyzed for energy value, moisture, ash, protein, fat, carbohydrates, fatty acid and amino acid composition, and macro- and micro-mineral content. Moreover, an online survey was conducted in order to evaluate the public’s current knowledge about invasive alien species and willingness to consume crayfish meat as a food product. Heavy metal concentrations (Hg, Pb, Cd) were below European Commission limits, confirming safety. The meat had a high protein content (16.68%), low fat (0.22%), and a favorable fatty acid profile with notable levels of omega-3 polyunsaturated fatty acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Predominant macro-minerals were K, Na, Ca, Mg, and P, while Zn, Cu, Fe, and Mn were the most abundant micro-minerals. Even though most participants (79.7%) were not informed about Faxonius limosus, the majority expressed willingness to participate in the assessment of new products made from invasive crayfish. These findings suggest that F. limosus meat is a nutritionally valuable and safe alternative protein source, with potential for sustainable food production and ecological management. Full article

Dual mycorrhizal symbiosis, i.e., the association with both arbuscular and ectomycorrhizal fungal symbionts, is an ambiguous phenomenon concurrently considered as common among various genetic lineages of trees and a result of bias in data analyses. Recent studies have shown that the ability to form dual mycorrhizal associations is a distinguishing factor for the continental-scale invasion of alien tree species. However, the phylogenetic mechanisms that drive it remain unclear. In this study, all the evidence on root-associated symbionts of Juglandaceae from South and North America, Asia, and Europe was combined and re-analysed following current knowledge and modern molecular-based identification methods. The Juglandaceae family was revealed to represent a specific pattern of symbiotic interactions that are rare among deciduous trees and absent among conifers. Closely related phylogenetic lineages of trees usually share the same type of symbiosis, but Juglandaceae contains several possible ones concurrently. The hyperdiversity of root symbionts of Juglandaceae, unlike other tree families, was concurrently found in Central and North America, Asia, and Europe, indicating its phylogenetic determinants, which endured geographical isolation. However, for many Juglandaceae, including the invasive Juglans and Pterocarya species, this was never studied or was studied only with outdated methods. Further molecular research on root symbionts of Juglandaceae, providing long sequences and high taxonomic resolutions, is required to explain their ecological roles. Full article

Arundo donax L. has been introduced in markets worldwide due to its economic value. However, it is listed in the world’s 100 worst alien invasive species because it easily escapes from cultivation, and forms dense monospecific stands in riparian areas, agricultural areas, and grassland areas along roadsides, including in protected areas. This species grows rapidly and produces large amounts of biomass due to its high photosynthetic ability. It spreads asexually through ramets, in addition to stem and rhizome fragments. Wildfires, flooding, and human activity promote its distribution and domination. It can adapt to various habitats and tolerate various adverse environmental conditions, such as cold temperatures, drought, flooding, and high salinity. A. donax exhibits defense mechanisms against biotic stressors, including herbivores and pathogens. It produces indole alkaloids, such as bufotenidine and gramine, as well as other alkaloids that are toxic to herbivorous mammals, insects, parasitic nematodes, and pathogenic fungi and oomycetes. A. donax accumulates high concentrations of phytoliths, which also protect against pathogen infection and herbivory. Only a few herbivores and pathogens have been reported to significantly damage A. donax growth and populations. Additionally, A. donax exhibits allelopathic activity against competing plant species, though the allelochemicals involved have yet to be identified. These characteristics may contribute to its infestation, survival, and population expansion in new habitats as an invasive plant species. Dense monospecific stands of A. donax alter ecosystem structures and functions. These stands impact abiotic processes in ecosystems by reducing water availability, and increasing the risk of erosion, flooding, and intense fires. The stands also negatively affect biotic processes by reducing plant diversity and richness, as well as the fitness of habitats for invertebrates and vertebrates. Eradicating A. donax from a habitat requires an ongoing, long-term integrated management approach based on an understanding of its invasive mechanisms. Human activity has also contributed to the spread of A. donax populations. There is an urgent need to address its invasive traits. This is the first review focusing on the invasive mechanisms of this plant in terms of adaptation to abiotic and biotic stressors, particularly physiological adaptation. Full article

Spalangia endius Walker, a pupal parasitoid of the alien invasive pest Zeugodacus cucurbitae (Coquillett), causes 33% host mortality. This study assessed whether combining S. endius with insecticides (abamectin, thiamethoxam, nitenpyram, emamectin benzoate, or beta-cypermethrin)—all effective against Z. cucurbitae—could enhance control efficacy. Among these, abamectin was the least toxic to adult S. endius. Surface contact treatments with 12 and 15 mg a.i./kg of abamectin did not significantly increase S. endius mortality. However, mixing 12 mg a.i./kg of abamectin into a honey solution to encourage ingestion decreased the survival, parasitism, and fecundity of S. endius. In olfactometer assays, S. endius adults avoided abamectin-treated host pupae, though prior exposure to abamectin mitigated this avoidance. The timing of abamectin soil application relative to host pupation and S. endius release affects host mortality. The most effective timing is spraying abamectin before host pupation (to expose Z. cucurbitae larvae) and then releasing S. endius. Field trials confirmed that combining abamectin (12 mg a.i./kg) with S. endius increased host mortality more than either treatment alone. In conclusion, abamectin (12 mg a.i./kg) is a suitable insecticide for combination with S. endius to control Z. cucurbitae. The application sequence should be spraying abamectin before hosts pupate and, only after that, releasing the parasitoid. Full article

Addressing environmental challenges requires the inclusion of local communities with relevant knowledge of the social–ecological system in which they are embedded, in addition to using transdisciplinary approaches that are critical to the co-production of successful and sustainable environmental solutions. A qualitative methodology was used to examine stakeholders’ views of decadal changes in Ria de Aveiro, a coastal lagoon on Portugal’s Atlantic coast. Seven focus groups were conducted, which included 42 stakeholders from coastal parishes, in order to obtain identical geographical representation with a study conducted a decade ago. Participants represented a diverse sample of groups interested in or affected by management options and activities in the lagoon system and were asked to reflect on the main changes that occurred over the last decade. Positive changes reflected an increase in the levels of environmental awareness, a positive trajectory of the environmental status of Ria de Aveiro, and a decrease in illegal fishing activities. Persisting concerns referred to the lack of an efficient management body for Ria de Aveiro, pressures related to changes in the hydrodynamic regime of the lagoon, the disappearance of native species and increase in invasive alien species, the abandonment of traditional activities (e.g., harvesting of seagrass and seaweed, salt production, agriculture in lagoon margins, and artisanal fishing), and the degradation and lack of maintenance of salt pans. Our findings highlight the importance of longer-term transdisciplinary and social–ecological research and illustrate how stakeholder views regarding the shortfalls of the movement towards the integrated management of ecosystems remain. Full article

Resprouting is a vital mechanism that enables plants to recover from severe damage caused by environmental or physical disturbances by using non-structural carbohydrates (NSCs), as reflected in their respiration activity. In this study, we focused on resprouting activity and carbon allocation at the organ level in the resprouter species R. pseudoacacia L. We compared the changes in biomass production, NSCs concentration, and respiration rates in each organ (leaf, stem, and root) of five- or six-year-old R. pseudoacacia L. between partial and complete stem loss (tall-stump, TS, and short-stump, SS, respectively) at 2, 4, 9, and 14 months after cutting. TS had greater resprout biomass than SS within two months after cutting, whereas SS experienced a loss of root NSCs before recovery. Compared to TS, SS had higher leaf respiration rates, likely for storage replenishment, whereas root respiration rates remained similar across treatments. The TS maintained NSCs levels during resprouting. However, the SS experienced temporary depletion and recovered within 14 months. Our findings provide new insights into the physiological characteristics of resprouters and invasive alien species with respect to organ loss and offer a novel understanding of efficient storage use during stress and low-cost carbon use for storage replenishment through rapid organ regrowth. Full article

The Argentine ant (Linepithema humile), listed among the world’s 100 worst invasive alien species, is notoriously difficult to control due mainly to its formation of large, expansive supercolonies. Despite the drawbacks of chemical control, biological alternatives have not been previously explored for this species. In this study, we evaluated six native entomopathogenic fungal strains against Argentine ants from four behaviorally distinct supercolonies, identified through aggression assays and collected from both urban and natural sites within the species’ native range. Ants were inoculated with 1 × 10⁸ conidia/mL using three methods: topical application, spray, and immersion. Mortality was recorded over 14 days, and the cause of death was confirmed by fungal outgrowth from cadavers. Among all strains, Beauveria bassiana Li053 consistently induced high mortality across all supercolonies and inoculation methods, with LT₅₀ values between 2 and 5 days and final mortality rates exceeding 80%. Fungal infection was confirmed in 87–92% of cadavers. Dose–response assays revealed that higher conidial concentrations accelerated and increased mortality, with an LC50 estimated at 1 × 10⁶ conidia/mL. These results demonstrate that B. bassiana Li053 is a promising candidate for the biological control of L. humile and merits further evaluation under field conditions. Full article

Invasive alien species are one of the main threats to global biodiversity, and pose significant management challenges in several areas outside their natural range. In southern Mediterranean Europe, the invasion of Acacia species is particularly severe and its control requires costly and often ineffective actions. The use of vermicompost derived from these species to replace peat-based substrates in horticulture offers a promising alternative to mitigate their economic and environmental impacts while enhancing the sustainability of their control. This study explored the potential of vermicompost produced from the fresh aboveground waste biomass (leaves + stems + flowers) of Acacia dealbata and Acacia melanoxylon (75:25 w/w), two of the most aggressive Acacia species in the Mediterranean, using Eisenia fetida over twelve weeks. In essence, this study aimed to evaluate the quality of the produced vermicompost and its suitability as a partial substitute for potting substrate in the production of cucumber (Cucumis sativus) seedlings for transplant. Four substrate mixtures containing 0%, 10%, 30%, and 50% of Acacia vermicompost (w/w), combined with commercial peat-based potting substrate and perlite (20%) were tested in polystyrene seedling trays. Seedling emergence, growth, and leaf biochemical parameters (photosynthetic pigments, phenolics, soluble sugars and starch, and total thiobarbituric acid-reactive substances—TBARSs) were evaluated. The results showed that the addition of Acacia vermicompost to the commercial substrate did not affect its germination but significantly enhanced seedling growth, particularly in mixtures containing 30% and 50% Acacia vermicompost. In addition, the absence of accumulation of TBARSs also reflected the superiority of these two treatments. These findings suggest that vermicompost derived from A. dealbata and A. melanoxylon biomass can be a viable peat-based substrate alternative for horticultural production, with the dual benefit of promoting sustainable agricultural practices and contributing to invasive species management. Full article

This paper provides data on non-native fungus-like organisms (Oomycota, kingdom Stramenopila), their diversity, and distribution in Lithuania and is an addition to a previously published checklist of alien true fungi (Chytridiomycota, Ascomycota, and Basidiomycota; kingdom Fungi). All available published data were summarized, and the analysis showed that approximately 25% of recorded Lithuania stramenopilous fungus-like organism species are alien. The compiled list represented herein includes 54 species of alien terrestrial and aquatic stramenopilous fungus-like organisms (Oomycota). Most alien Oomycota are obligate pathogens of terrestrial plants. Aquatic organisms are represented by one alien dangerous crayfish pathogen, Aphanomyces astaci, which is currently noted as extinct in Lithuania. The taxonomy of the listed alien species of Oomycota has been revised, and the species names have been adjusted to reflect current nomenclature changes. The taxonomical and ecological analysis demonstrated the prevalence of terrestrial parasitic Peronosporales reported in Lithuania Oomycota and the highest diversity of alien species belonging to the Peronospora genus. The chronology of appearance, distribution within the country, and current status of these non-native organisms were assessed, and some of the most economically or ecologically important harmful invasive species were discussed. Full article

Disturbed ecosystems are particularly susceptible to biological invasions. Increasing freshwater salinization, caused by anthropogenic factors, can alter the phytoplankton community and favour newly arrived halotolerant species. This study investigates the halotolerance of four Nostocalean cyanobacterial species—the native to Europe, Aphanizomenon gracile, and alien Chrysosporum bergii, Cuspidothrix issatschenkoi, and Sphaerospermopsis aphanizomenoides—using monoculture experiments under varying NaCl concentrations. Additionally, we performed two microcosm experiments to explore shifts in biodiversity in freshwater phytoplankton communities sourced from artificial reservoirs and assess their susceptibility to cyanobacterial invasion under salinity stress. Results showed that all Nostocalean cyanobacteria were halotolerant under mild salinities (up to 1 g/L NaCl), with Chrysosporum bergii and Sphaerospermopsis aphanizomenoides demonstrating the most salt tolerance. In the microcosm experiment, changes in community composition were driven by the halotolerance of dominant groups. Water body 1, dominated by Bacillariophytina, reduced its biomass of phytoplankton at high salinity (5 g/L NaCl), while water body 2, dominated by Chlorophytina, remained stable regardless of disturbance. Both cyanobacteria successfully invaded both halotolerant and halosensitive communities, increasing their dominance as salinity rose. Our findings suggest that anthropogenic stressors such as freshwater salinization can alter the phytoplankton community and increase a competitive advantage to certain taxa, including widespread alien cyanobacteria, potentially promoting invasions and bloom formation. Full article

Conservation of ecologically important freshwater mussels is high on the international agenda, but there is only limited knowledge about the status of rare unionid species in arid and semi-arid areas which are particularly vulnerable. One such example concerns Anodonta vescoiana which was recognized as one of the few endemic species of unionid mussels from Iraq and was restricted to the marshes of southern Mesopotamia and its connected river systems. The last confirmed report of A. vescoiana was in 2009 from the Al-Ezz River. We conducted extensive field surveys during the years 2021 and 2022 at approximately 20 freshwater sites, but we failed to observe any live or dead specimens, suggesting a probable extirpation or severe decline. In contrast, we documented the invasive Sinanodonta woodiana at numerous sites across the Tigris–Euphrates basin including the Al-Ezz River. This documentation of S. woodiana indicates successful establishment of the species and colonization of freshwater systems modified by anthropogenic practices, which include alterations of hydrological dynamics and ecological conditions. Here, we compile existing evidence of the global ecological impacts and development of S. woodiana invasion, while also highlighting Iraq as an important example of the displacement of native unionid mussel species by invasive alien unionids. We assessed the factors that contributed to the disappearance of A. vescoiana in Iraq including biological competition (with S. woodiana), salinity stress, habitat fragmentation, and pollution. The time window to act and prevent the further decline of rare unionid species in Iraq, as well as other arid and semi-arid areas which face similar threats, is short. Urgent actions include systematic monitoring to identify remnant populations, implementing biosecurity policies (for fisheries or habitats), and restoration (of habitats) to secure the long-term persistence of remaining unionid diversity. Full article