Effects of biomass feedstock and hydrothermal temperature on the molecular composition and bioavailability of invasive plant-based hydrochar-derived dissolved organic matter.

Pastoral resilience under threat: impacts of climate change, invasive plant species, and traditional ecological knowledge erosion in the Kashmir Himalayas

ABSTRACT Garlic mustard (Alliaria petiolata), an invasive plant of the North American forest understory, is the target of importation biological control programs in both the United States and Canada. After host range testing was completed in the US, a garlic mustard rosette crown-mining weevil from Europe, Ceutorhynchus scrobicollis, was released in Canada in 2018 and has recently been approved for release in the United States. We defined temperature-dependent thresholds for C. scrobicollis oviposition behaviour and cumulative thermal units required for F 1 development within garlic mustard rosettes. These thermal requirements of C. scrobicollis were then used to inform a degree-day model to predict the potential geographic distribution of the imported biological control agent in the Great Lakes region of North America. We found that Cumulative Degree Days accumulated during the rosette seasons in 2020 through 2024 were sufficient for C. scrobicollis parasitism of garlic mustard rosettes to take place in Southern Ontario, as well as the central and upper Midwest and Northeast regions of the United States.

Short-term effects of a tilling-based Spartina alterniflora removal project on intertidal macrobenthic communities.

Alien plant invasions in forests can severely threaten native biodiversity and ecosystem functioning. Canopy closure in deciduous forests can cause variability in light levels, but light levels in forest edges and evergreen forests are constantly high and low, respectively. We tested how light conditions and light variability affect invasiveness of alien plants by growing five pairs of invasive and noninvasive alien species under conditions of high, variable (with high light in the initial phase and low light in the latter phase of the experiment) and low light intensities. Total duration of the experiment was 200 days. The alien plants were grown singly, or competed with a native deciduous or evergreen tree seedling. Overall, invasive plants produced marginally more biomass than noninvasive plants. From high to low (averaged across variable and low) light conditions, biomass of invasive plants decreased less than that of noninvasive species (−26.7% versus −37.7%), indicating that invaders may have a greater capacity to invade forests than noninvasive plants. From low to variable light conditions, biomass of invasive plants increased more than that of noninvasive species (63.7% versus 48.9%), indicating that the advantage of invaders over noninvasive species is most pronounced under variable light conditions. Competition with the deciduous tree reduced biomass more for the noninvasive plants than for the invasive plants, indicating that interspecific competition may further explain why some alien species can invade while others cannot. Our results indicate that high light early in the season benefited more for the invaders, and reduced irradiance from the middle of the experiment limited growth of the noninvasive plants more than that of the invasive plants. Together, our results suggest that variable light levels, simulating those in deciduous forests or caused by disturbances, may promote the invasiveness of alien plants.

Black shank disease caused by Phytophthora nicotianae threatens global tobacco production, while the invasive plant Mikania micrantha is a high-biomass source of antimicrobial secondary metabolites. To promote the resource utilization of invasive plants for green disease management, this study investigated the antifungal activity and underlying mechanisms of mikanolide, a sesquiterpene lactone derived from M. micrantha, against P. nicotianae. Mikanolide inhibited mycelial growth in vitro (EC50 = 6.519-8.954 μg mL-1), outperforming azoxystrobin. Pot trials demonstrated strong in vivo efficacy, reducing disease incidence and index to 33.33% and 11.48%, respectively. Mechanistically, mikanolide disrupted cell membrane integrity and induced oxidative stress by suppressing ATP synthesis and antioxidant enzyme activities. Transcriptomics revealed upregulation of acetyl-CoA carboxylase and ATP-dependent protease La, with downregulation of malate synthase A. Molecular docking confirmed strong binding affinities to ATP synthase (-7.3 kcal mol-1) and succinate dehydrogenase (-8.0 kcal mol-1). Mikanolide suppresses P. nicotianae through disruption of membrane integrity, oxidative stress, and energy metabolism. This study provides a theoretical basis for the resource utilization of M. micrantha and the green management of P. nicotianae. © 2026 Society of Chemical Industry.

Climate change, together with intensifying human activities, is reshaping global plant invasion dynamics and increasingly threatening ecosystem stability and biodiversity. Cockleburs are highly invasive weeds with strong ecological plasticity and dispersal capacity, causing widespread impacts on agricultural systems and native ecosystems. Here, we used the maximum entropy (MaxEnt) model to assess the current (2001-2020) and future (2021-2040, 2041-2060, and 2061-2080) potential distributions, key driving factors, and centroid shifts of four invasive cocklebur species-Cyclachaena xanthiifolia (=Iva xanthiifolia), Xanthium chinense, Xanthium italicum, and Xanthium spinosum-at the global scale under current climate conditions and three Shared Socioeconomic Pathway scenarios (SSP126, SSP245, and SSP585). Species occurrence records were integrated with climatic, topographic, and anthropogenic variables to project habitat suitability. Model performance was robust, with mean training and testing area under the receiver operating characteristic curve (AUC) values > 0.8 for all species and mean true skill statistic (TSS) values > 0.8 for three species (0.660 for Xanthium spinosum). Suitable habitats were jointly shaped by climatic and anthropogenic factors, although the dominant drivers differed among species. Cyclachaena xanthiifolia and Xanthium spinosum were primarily constrained by temperature and precipitation, whereas Xanthium italicum and Xanthium chinense were more strongly associated with human activity. At present, suitable habitat areas for Cyclachaena xanthiifolia, Xanthium chinense, Xanthium italicum, and Xanthium spinosum were 1196.92 × 104, 358.76 × 104, 888.34 × 104, and 1985.14 × 104 km2, respectively. Future projections indicated overall contractions in suitable habitat, with pronounced interspecific variation. Xanthium chinense showed the largest mean decline (-161.23 × 104 km2 relative to the present), whereas Cyclachaena xanthiifolia experienced the smallest reduction (-53.15 × 104 km2 on average). Centroid analyses further suggested overall shifts toward higher latitudes and elevations under warming scenarios. Despite uncertainties related to climate scenario variability and assumptions inherent in species distribution modelling, these findings provide quantitative evidence to support global invasion risk assessment and climate-adaptive management of invasive cockleburs.

Species invasion is one of the key issues in global ecosystems. This study investigated the changes in the rhizosphere community structure of complete ammonia-oxidizing (Comammox) bacteria after the invasion of the long-rooted submerged macrophyte Vallisneria spiralis L. into the community of the short-rooted submerged macrophyte Myriophyllum spicatum L. Different planting ratios simulated varying invasion intensities. Increasing invasion intensity significantly altered rhizosphere factors, reduced dissolved organic carbon (DOC), and lowered pH, thereby causing distinct alterations in the rhizosphere environment. Comammox Clade A remained dominant with stable abundance, indicating strong adaptability. In contrast, Clade B abundance increased under low-moderate invasion but declined sharply under high intensity, suggesting a preference for mixed roots or low-intensity invasion. Higher pH and DOC provided a stable niche for Clade A. High invasion intensities elevated NH4+-N and NO3--N concentrations, which coupled with stronger oxidative conditions promoted AOB and certain Clade A subgroups, thereby suppressing the low-nitrogen-adapted Clade B. This study demonstrates that submerged macrophyte invasion reshapes the rhizosphere environment and drives Comammox community differentiation, offering new insights into plant invasion's ecological effects and nitrogen cycling regulation.

Summary Waste management is one of the major environmental challenges of the twenty-first century. This Perspective examines how vegetation dynamics at composting facilities and landfills both reflect and influence anthropogenic environmental change. We define our use of the Anthropocene as a human-dominated epoch that is functionally and stratigraphically distinct from the Holocene, and we argue that waste-derived ecosystems constitute model systems for detecting its signals through technogenic substrates and synanthropic succession. Although composting reduces pressure on landfills, incomplete processing of biowaste can disseminate propagules of invasive plant species. Landfills, shaped by disturbance and altered edaphic regimes, support synanthropic plant assemblages dominated by neophytes that act as bioindicators of leachate stress and other pressures. At the same time, spontaneous vegetation provides functional benefits, including slope stabilization, organic matter accumulation and habitat provision during early successional stages. We bring together information on risks and functions, link ecological criteria to permitting, monitoring and post-closure management pathways, and outline practical considerations for integrating plant-based indicators with geochemical screening. These steps enable ecologically sensitive strategies to be implemented that mitigate biodiversity risks while leveraging succession to improve the resilience of waste-derived landscapes.

Invasive plant species pose a major threat to wetland ecosystems. One effective way to control the spread of invasive plants is to intercept them early in the invasion process. Species distribution models (SDMs), fit with covariates related to habitat suitability, can predict where new invasions are likely to occur. For species that have not yet filled their niches during early invasions, dispersal dynamics such as proximity to known presences and/or human vectors may control spread as much as habitat suitability. Yet, many SDMs assume that the species has filled its niche, incorporate only biophysical predictors, and do not consider spatial processes. Including dispersal dynamics can account for nonequilibrium processes, thereby improving the utility of invasive SDMs. We quantified the importance of environmental (abiotic and biotic) and dispersal-related drivers (anthropogenic and endogenous) on the occurrence and abundance of Hydrocharis morsus-ranae (European frogbit; EFB), a floating aquatic plant. We fit Bayesian hurdle models with integrated nested Laplace approximations (INLAs) to 2487 quadrat observations recorded across coastal wetlands in Michigan, USA from 2011 to 2021. We found that EFB occurrence was most strongly associated with distance to the nearest known population (m), a proxy of local dispersal. EFB occurrence also exhibited a nonlinear relationship with water depth (cm), demonstrating an optimal range of water depth for EFB. Occurrence was negatively associated with wave energy and positively associated with cattail (Typha spp.) abundance, which we attribute to protection from waves. Surprisingly, none of our predictors had any meaningful associations with EFB abundance, suggesting that it may be too early in EFB's invasion stage to quantify important drivers of abundance once at a site, or we did not include important factors that operate at the scale at which these growth processes occur. Moreover, the dispersal model yielded slightly better predictive capacity of EFB across Michigan. Overall, our results indicate that local dispersal is the primary driver of occurrence for an invasive species that has not yet filled its niche, whereas additional data or SDMs may be necessary to (a) better predict its abundance once established in coastal wetlands and (b) identify susceptible areas to future invasions.

ABSTRACTManaging biological invasions is one of the top priorities of biodiversity conservation. Invasive plants are a well‐known threat to native plant and animal communities, and understanding their ecological impacts is critical to developing individualized management strategies. While much is known about the impacts of invasive plants, there are still questions about the per capita effects along invasion abundance gradients across levels of biological organization. In this study we investigate how the ecological impacts of the invasive grass Bothriochloa ischaemum vary across a gradient of invasion and whether effects are consistent across population (abundance and functional traits of a dominant native grass, Schizachyrium scoparium) and community (species richness and composition) levels. We found that most of the ecological impacts of B. ischaemum scale linearly with its abundance across population and community levels. Increasing invasion reduces the height and abundance of the dominant native S. scoparium individuals and shifts their functional trait composition. Increasing invasion also reduces cover of native C3 and C4 grasses, total foliar cover, subdominant foliar cover, species richness, and leads to shifts in species and functional group composition. However, the impact on legume abundance saturated at low invader abundance (1%–15% cover) and remained constant as invader abundance increased. We show that the direct ecological impacts of invasive species may be compounded by shifts in the functional traits of dominant native species toward more conservative traits and shifts in species and functional group composition, leading toward a shift in population and community structure and function.

Biological invasions are a leading cause of the ongoing biodiversity crisis, and particularly so on islands. However, the role of invasive alien plants (IAPs) as a driver of native plant declines and extinctions remains unclear. The inherently slow and gradual nature of plant extinctions, especially that of long-lived woody species, could be a reason. Here, we examined temporal trends in subpopulations of 28 threatened endemic tree (TET) taxa. We questioned the frequency with which they decline in association with IAPs on Reunion Island (South-West Indian Ocean), and asked whether the most susceptible TET taxa exhibit characteristics that could reveal the underlying ecological mechanisms. We resurveyed 182 historically described subpopulations and tested whether observed trends of juvenile and adult TETs correlate with the abundance in IAPs using path analyses, while distinguishing TET taxa with respect to their leaf–height–seed characteristics and extinction risk. The trend of adult TETs was not affected by IAPs but that of juvenile TETs was negatively correlated with the abundance of IAPs in the understory layer. This was particularly the case for TET taxa with conservative resource-use strategies (low specific leaf area or low maximum height), whose juveniles might be particularly susceptible to competition with IAPs, but not for TET taxa with large seeds, whose metabolic reserves make seedlings more likely to attain a critical size. These findings suggest that IAPs can significantly contribute to the extinction dynamics of trees, primarily by limiting regeneration through competitive exclusion, and that their impacts vary depending on the traits of the affected taxa. • Historical populations of threatened trees were resurveyed to estimate their trends. • Population trends were tested for correlation with abundance in invasive plants. • Populations of juvenile trees decreased with increasing understory invasions. • Susceptibility of juvenile trees was trait-dependent. • Invasive plants can push trees towards extinction by disrupting regeneration.

Green valorization of invasive alien plants using a novel method of simultaneous hydrothermal treatment and ball milling

Herbivore defense syndromes differ between native and invasive plant species

Drought-nitrogen synergy reshapes stress-adapted fungal consortia via plant-soil feedback in invasive plant Cenchrus pauciflorus

Integrative engineering of biomass-derived CQDs for enhancing photosynthesis of microalgae coupled with bioethanol production.

Abstract: The speaker contemplates an invasive plant called Devil's Beggarticks, which has populated the banks of a suburban creek, and her own implication in the environmental changes made apparent by the plant. An ars poetica leaning into fall and winter imagery as well as text elements, such as punctuation, the poem explores the speaker's writing process during a loved one's cancer treatments. At the fall equinox, hiking in mountain ecosystems, the writer contemplates seasonal changes (and what doesn't change with seasons), while confronting recent griefs and mortality itself.

Scoring Invasive Plant Species of European Russia by Their Environmental and Socioeconomic Impacts

Elevated CO2 alters resource allocation, which should benefit species that produce metabolically expensive specialized metabolites (in orange). Increasing biochemical production will have consequences for plant competition, plant-soil feedbacks, and ecosystem processes, and can create fitness advantages for these species over species that do not produce these chemicals (in black).

Water hyacinth is an aggressive invasive plant. The infestation can double in size every 5 days under ideal conditions, quickly covering the surface of the water and taking over an entire stream. This plant's ability to tolerate a wide range of temperatures, nutrients, and pH levels gives it a superior advantage over other native freshwater plants whose growth is generally slower. In the current research, the growth of the water hyacinth plant was treated in an environmentally friendly manner. This is done by spraying a thick layer of the nano-chitosan mixture with wax repeatedly for 10 consecutive days. The result was yellowing and gradual wilting of the leaves. From the first 24 hours of spraying the nano-mixture until 10 days of treatment have passed. During the treatment period, stiffness, blackening, and tearing of the leaf edges were observed, which led to a decrease in the wet weight from (109 - 75) grams. The number of dead leaves increased from (1 - 29) and the length of the plant decreased, reaching (40 - 26) cm compared to the control plant. Decreased chlorophyll reaching (28.3 – 9.8) cm compared to the control plant The water evaporation rate was measured, reaching (23-20), and the laboratory temperature was measured continuously during the plant’s acclimatization period and after the treatment period. The current study aims to identify the effect of spraying a mixture of chitosan nanoparticles with wax on the growth and production water hyacinth plants, evaluate the amount of water lost in evaporation and transpiration, and the possibility of developing an effective and successful biological control strategy in the biological control of invasive plants.