Environmental Sciences Europe最新文献

River networks are highly dynamic environments, where local conditions range from lotic to lentic, promoting the co-occurrence of highly diverse biota. These environments are threatened by various human-induced stressors, among which water scarcity affects more than half of all running waters globally. While flow intermittence occurs naturally, its spatial and temporal extension is spreading under climate change and human pressures, endangering river biota. Here, we performed a mesocosm study aiming to investigate how flow reduction during drying events affects macroinvertebrate communities from different mesoscale habitats, such as riffles and pools. The experiment was performed in a replicated flow-through mesocosm system during summer 2021. We tested the effects of both intermittent and prolonged three-month-long flow reduction on macroinvertebrate communities from riffle and pool mesohabitats in terms of community composition, and resilience and resistance functional traits (e.g., resistance form, current preference, locomotion, dispersal strategy, reproduction drift propensity, etc.). Sampling was performed before, during, and after the exposure to flow reduction to assess both the direct effect of water scarcity and the post-drought recovery of macroinvertebrate communities. We found that communities from riffle habitats were more severely affected by flow reduction during drying events, showing a more severe decline in taxonomic richness and reduced abundance of desiccation-sensitive organisms under prolonged flow reduction treatments compared to intermittent ones. During flow reduction events, we did not observe a consistent taxa turnover toward drought-tolerant taxa, with only a few resistance trait modalities (e.g., organisms with tolerance for higher water temperature or interstitial ones) significantly associated with prolonged flow reduction. Moreover, the communities from riffle mesohabitats did not fully recover even one month after normal flow conditions were re-established, showing a low post-drought resilience. In pool mesohabitats, we did not detect significant effects of intermittent or prolonged flow reduction, with a community composition dominated by generalist taxa. These findings highlight the importance of accounting for mesohabitat-specific responses to drying when evaluating the ecological consequences of increasing flow intermittence and suggest that habitat heterogeneity plays a critical role in shaping the resistance and resilience of macroinvertebrate communities under water scarcity.

Graphene and its derivatives such as graphene oxide (GO) and reduced graphene oxide (rGO) have been extensively utilised due to their exceptional physicochemical properties and versatility in biomedicine, electronics, and energy storage. Their increasing use has led to environmental release, raising concerns over their ecological toxicity, particularly in aquatic systems. Extracellular polymeric substances (EPS), secreted by microalgae like Chlorella sp., can interact with nanomaterials and modulate their environmental behaviour. This study examined the impact of two categories of extracellular polymeric substances, extracted from marine Chlorella sp., loosely bound (LB-EPS) and tightly bound (TB-EPS), on the toxicity of graphene family nanomaterials (GFNs) at an ecologically relevant concentration of 1.25 mg/L. All GFNs generated an increased amount of reactive oxygen species along with malondialdehyde (MDA) generation and exacerbated antioxidant enzyme activities. This resulted in the inhibition of algal growth and photosynthesis, with toxicity ranking as rGO > GO > graphene. Surface characterisation, such as surface charge, wettability, and fluorescence analyses, confirmed EPS adsorption onto GFNs. Notably, EPS interaction reduced toxicity, with TB-EPS showing greater protective effects than LB-EPS. EPS eco-corona acted as a physicochemical barrier, attenuating the direct interaction of GFNs with algal cells, thereby lowering oxidative stress and restoring photosynthetic function. These findings highlight the critical role of different types of algal-EPS in mitigating nanomaterial toxicity and offer new insights into their ecological risks in marine environments.

Microplastic (MP) contamination constitutes a widespread and intensifying global environmental challenge, adversely affecting aquatic, terrestrial, and atmospheric systems. Avian species are especially susceptible to microplastic exposure due to their ecological significance across diverse trophic levels and habitats, mostly through trophic transfer from consuming contaminated prey and inhaling airborne microplastics. This research uses regurgitated pellets of the Egyptian vulture as a pellet-based bioindicator tool to assess terrestrial microplastic contamination in two distinct regions of Türkiye (Ankara and Çorum). Here, a total of 307 microplastic particles were identified from 98 pellets, with a 93.33% overall occurrence rate and 100% contamination in Çorum samples. MP abundance was significantly higher in Çorum (mean = 15.0 ± 2.4 items per pellet) than in Ankara (mean = 1.15 ± 0.3; χ² = 58.50, p < 0.001). The predominant polymers were polyethylene terephthalate (PET, 31.3%), polyacrylonitrile (PAN, 18.2%), and polypropylene (PP, 15.6%), with fibers being the dominant shape (70.7%) and transparent and blue the most frequent colors (50.2% combined). Statistical analyses revealed a negative correlation between MP size and pellet weight (r = –0.32, p < 0.001), confirming the influence of degradation and feeding behavior on MP retention. The widespread presence of MPs in this endangered species highlights trophic transfer and atmospheric deposition as key mechanisms of contamination. Egyptian vultures may serve as an effective bioindicator species for terrestrial microplastics, reflecting broader contamination within the terrestrial food web. These findings underscore the urgent need for improved plastic waste management in rural environments and the implementation of long-term monitoring to mitigate ecological and health risks.

Graphical abstract

The present study examines the impact of interaction terms of energy transition*governance and research and development expenditure*governance on load capacity factor by employing Method of Moments Quantile Regression and Feasible generalized least squares in 10 BRICS (BRICS countries include: Brazil, Russia, India, China, South Africa, Egypt, Ethiopia, Iran, Saudi Arabia, and the United Arab Emirates) countries using data from 1990 to 2020. The Load Capacity Factor considers both the demand and supply aspects of the environment, unlike CO₂ emissions and ecological footprint. The study found that economic growth and depletion of natural resources are the main causes of environmental degradation, whereas environmental sustainability is linked to an upsurge in research &development investments, adoption of advanced technologies, and a shift to renewable energy sources. Moreover, governance promotes an energy transition and research and development investments to achieve environmental sustainability. The panel causality test revealed unidirectional causation from natural resources depletion and interaction of energy transition*governance to load capacity factor, while remaining variables show bidirectional causality. The study recommends that the BRICS nations’ governments utilize energy and environmental policies to improve environmental sustainability by promoting investments and initiatives in renewable sources.

Background

The high level of environmental contamination from metals requires us constantly to study the relationships between their levels in the body and potential health problems. The possibility of easy, non-invasive sampling made hair a popular matrix for such studies. Many factors, however, may influence the levels of metals in hair and need to be borne in mind. The purpose of this study was therefore to compare metal concentrations (Ca, Cd, Cu, Fe, Hg, K, Mg, Ni, Pb, Zn) in 145 women who employed a variety of hair-care habits (coloring and washing frequency) and lived in three regions of Poland with different levels of urbanization (Malopolskie, Podkarpackie and Swietokrzyskie), and to verify their dependence on air pollution proxied by PM10 data (gathered for 2013 and 2014). Since pre-cleaning procedure may alter hair trace elements composition, we did not clean samples prior to analysis to assess the total metal burden - incorporated from the body and from external contamination - and thus provide an important measure of overall environmental exposure.

Results

Air pollution significantly affected hair Ca, Hg, Mg, Pb, and Zn levels in both 2013 and 2014. A clear increasing trend in Ca and Pb concentrations was observed with rising PM10 levels. Washing frequency increased levels of Zn in hair, while coloring increased Ca and Mg levels, which indicates that such regimens influence mineral hair composition rather than xenobiotic metal content.

Conclusions

The region where women live appears to be the most significant factor influencing metal concentrations in their hair. Since geographical location—particularly differences in industrial activity—affects metal levels in unwashed hair, we propose that this matrix could be used to assess overall metal exposure and may also provide insights into the level of air pollution in a given area.

Chemical pollution is identified as a significant driver of biodiversity loss, raising concerns about the effectiveness of current environmental risk assessment (ERA) practices. Conventional ERA approaches primarily rely on the endpoints of mortality, growth, and reproduction, often failing to capture the full scope of potential effects that chemicals can have on organisms. This is potentially problematic in cases of chemicals causing neurotoxicity, immunotoxicity, and metabolic toxicity, which have recently been introduced to the discussion under REACH by the new report of the European Chemical Agency (ECHA) on Key Areas of Regulatory Challenge. For these modes of action (MoAs), which have to date been discussed primarily in the context of human toxicity, there is currently no established approach for addressing them in ERA. This is despite the fact that these chemicals often have sublethal effects on traits linked to potential effects on population-relevant endpoints (e.g., foraging behaviour). In this study, we evaluated the importance of non-conventional sublethal endpoints for hazard and risk practices. We categorised endpoints into conventional (CE; i.e., defined by standardised guidelines), semi-conventional (semi-CEs; i.e., defined by standardised guidelines but only for a limited number of species), and non-conventional endpoints (NCE; i.e., ecotoxicological measurements not defined by standardised guidelines and so going beyond conventional measurements). In this conceptual review, we selected case studies that evaluated both conventional and non-conventional endpoints to evaluate the importance of NCEs for the assessment of the emerging hazards in comparison to CEs, focusing on (1) sensitivity (effect levels), (2) mechanistic understanding, and (3) population-level effects. Our assessment shows that using NCEs can improve mechanistic understanding of chemical hazards and provide important information about the chemicals’ MoA. Comparisons between NCEs and CEs at the individual and population levels revealed that in 13% of cases, NCEs showed effects when CEs were unaffected. NCEs were generally more sensitive, being on average 56 times more sensitive than mortality, 8 times than reproduction, and 2 times than growth—in 9 cases, the NCEs were more than 1000 times more sensitive than the CE. NCEs showed unconventional links to the population level that would have gone undetected in the current ERA system (e.g., changes in boldness behaviour affecting reproduction in fish). We propose a first approach to address environmental hazard identification and risk prediction for neurotoxic, immunotoxic, and metabolic toxic compounds by organising relevant NCEs according to an Adverse-Outcome-Pathway (AOP) structure, and a MoA-based AOP framework.

Nitrogen pollution represents one of the most significant threats to European freshwater ecosystems, with nitrite (NO₂-N) standing out as a highly toxic compound for aquatic organisms, particularly vertebrates. Despite its recognized toxicity, little is known about its effects on invertebrates, even as riverine ecosystems experience profound species turnover. Here, we investigated the lethal and sublethal effects of nitrite on three representative amphipod species (Gammarus fossarum, G. pulex, and G. roeselii), which occupy distinct river sections and ecological niches. These species serve as models for assessing how nitrogen pollution may shape invertebrate communities across freshwater habitats. A series of laboratory bioassays revealed that G. fossarum, a species associated with upstream sections and pristine conditions, was the most sensitive to nitrite exposure, followed by the midstream species G. pulex and the long-established downstream species G. roeselii. To contextualize these findings, we compared the nitrite vulnerability of these amphipods with that of other freshwater invertebrates, offering a comprehensive perspective on how nitrogen pollution reshapes aquatic communities. While many invertebrate groups exhibit lower vulnerability to nitrite due to their reliance on hemocyanin—an oxygen-transport molecule mostly unaffected by nitrite oxidation—our results underscore significant interspecific differences in tolerance. For sensitive insect species, lethal effects occurred already at environmentally relevant concentrations, highlighting their exceptional vulnerability. In contrast, more tolerant groups such as amphipods survived higher concentrations, yet still displayed sublethal impairments, most notably a reduced leaf litter consumption—a key process in stream nutrient cycling—and altered behavioral responses at comparable exposure levels. Molluscs exhibit the highest tolerance, whereas insects are the most sensitive. Among crustaceans, tolerance varies widely, with a relationship to chloride content of the water mitigating the toxicity of nitrite. Chloride concentrations generally rise along the course of a river, placing upstream regions with naturally low chloride levels and their species at heightened risk. These differences highlight the potential role of nitrogen pollution as a driver of species turnover, particularly in multistressor environments. By linking species-specific sensitivity to broader ecological processes, like leaf litter consumption, this study provides critical insights into cascading effects of nitrogen pollution on freshwater biodiversity and ecosystem stability.

The increase in global antibiotic consumption has intensified the presence of these substances in aquatic ecosystems. Related to this, phytoremediation studies have gained prominence due to their high efficiency in mitigating the contamination of emerging pollutants in aquatic ecosystems. In this context, the current study aimed to investigate the occurrence of antibiotics in the aquatic environment the efficiency of the macrophyte Salvinia auriculata in phytoremediation, and the bioaccumulation, depletion, and genotoxic effects in Astyanax bimaculatus exposed to enrofloxacin (EFX) and chloramphenicol (CAP). Environmental samples were collected from the Piracicaba River (SP) at different seasonal periods and analysed using LC–MS/MS. Antibiotics from the tetracycline, fluoroquinolone, and phenicol classes were mainly quantified, with higher concentrations in the dry season. Phytoremediation experiments with S. auriculata demonstrated removal rates greater than 95% for EFX, especially in treatments with higher biomass, while CAP showed lower removal rates (45%). In bioaccumulation and depletion tests, CAP showed greater persistence in fish tissues, while EFX was rapidly eliminated. The presence of S. auriculata modulated bioavailability, reducing the concentration in water, but, in some cases, increasing the absorption rate in fishes. In addition, genotoxic analyses revealed a CAP-induced increase in the frequency of micronuclei (MN) and nuclear abnormalities in erythrocytes (ANEs), an effect that was attenuated in the presence of the macrophyte. The results highlight the potential of S. auriculata as an effective phytoremediation tool, capable of reducing the antibiotic load in the environment and partially mitigating the genotoxic effects in aquatic organisms.

RNA interference is a powerful gene regulatory strategy in which RNA molecules participate in the sequence-specific inhibition of gene expression by dsRNA, either through transcriptional or translational suppression. Since the RNA-mediated interference (RNAi) has been acknowledged as a natural method for controlling gene expression in higher species, ranging from plants to people, it has a stronger impact on crop improvement. In this review, we focused on additional research in numerous areas including microRNA (mi RNA), small interfering RNA (siRNA), plant RNAi transformation vector and transgenic RNAi plants, and off-target effects. The RNAi mechanism involves small interfering RNA molecules that efficiently down-regulate desired genes. Manipulating genes through small RNA interference can lead to improved traits in crops, such as resistance to biotic and abiotic stresses, as well as nutritional enhancement through bio-fortification. We also summarized the successful use of RNAi in altering several desired traits in plants such as changes in morphology, increased nutrients content, enhanced plant biomass and grain yield, extended shelf life, development of seedless fruit, induction of male sterility, enhanced synthesis of secondary metabolite, improved biofuel production and enhanced defense against biotic and abiotic stresses. This review article presents an outline of the ideas and mechanisms of the RNAi approach in crop improvement through gene regulation and explores various applications across diverse aspect of crop enhancement while addressing current challenges.

Background

Microplastic pollution has been widely studied in aquatic environments, but limited evidence is available on its presence in agricultural soils, especially in India. Farmlands are increasingly exposed to plastic debris through irrigation, fertilizers, mulching materials, and other human activities. Understanding the occurrence and characteristics of microplastics in soil is critical for assessing potential ecological and agricultural risks. This study investigates the presence, types, and possible sources of microplastics in banana farmland soils of Kasaragod District, Kerala.

Results

A total of sixteen soil samples were collected in the month of February from banana cultivation areas in triplicates (n = 48). Microplastic contamination was confirmed in all samples, with concentrations ranging from 19.17 to 319.17 particles per kilogram of soil, and an average of 137.19 particles per kilogram of dry soil. Morphological analysis by microscopy revealed that fibres were the most dominant form (72%), followed by fragments (15%), microbeads (10%), and films (3%). Most of the particles black, blue, and red being the prevalent colours, with possible inputs from both agricultural and domestic sources. Polymer identification using Fourier transform infrared spectroscopy confirmed polypropylene (70%) and polyethylene (30%) as the main polymers. Pollution hazard index analysis suggested that all sites posed medium to high ecological risk with the highest PHI value recorded as 1100. Statistical analysis demonstrated significant differences in microplastic abundance among locations, and correlation analysis indicated a strong association between fibre particles and coloured microplastics, highlighting their link to human activities.

Conclusions

This study provides the first documented evidence of microplastic contamination in banana farmland soils in India. The findings demonstrate that agricultural soils can act as an important sink for microplastics and are vulnerable to ongoing plastic deposition from multiple sources. The dominance of coloured microplastic fibres suggests substantial anthropogenic contributions. The observed ecological risks underscore the urgent need for improved management of plastic waste, better agricultural practices, and stronger regulatory measures to protect soil quality and ensure sustainable farming systems. This highlights the critical need for integrating sustainable plastic management strategies within agricultural practices to prevent long-term soil degradation and ensure food security.