Biodiversity surrogates, such as the Indicator Species Approach (ISA) and Higher-Taxon Approach (HTA), offer cost-effective alternatives to species-level identification. However, their reliability varies across studies. This article presents a large-scale evaluation of ISA and HTA using nearly 10,000 freshwater macroinvertebrate assemblages. We focused on two common surrogates: the EPT group (Ephemeroptera, Plecoptera, Trichoptera) as a proxy for the entire macroinvertebrate community (ISA), and family-level data as a proxy for species-level data (HTA). We tested whether sampling effort, the species:higher-taxon ratio, the proportional abundance of the most common species (i.e., community evenness), or environmental factors (human pressures, climate) influence surrogate performance. Overall, both ISA and HTA reliably represented alpha diversity and community structure, but performance was strongly context-dependent. Generalized Additive Mixed-effects Models (GAMMs) showed that assemblage characteristics were the main drivers of surrogate efficacy. A high species:higher-taxon ratio negatively affected family-based surrogates, indicating better performance in regions with fewer species per family. Community evenness had a positive effect, improving the reliability of family-based surrogates in communities dominated by a few species. Sampling effort also influenced the performance of EPT-based surrogates, improving congruence with species-level data under greater effort. Importantly, environmental variables had no significant effect, suggesting these surrogates are robust across broad environmental gradients; however, finer-scale studies that incorporate local, site-specific environmental variables - such as water quality parameters - remain necessary to fully assess the general applicability of these approaches. Our findings highlight that surrogate performance depends not on the method alone, but on taxonomic resolution, community structure, and sampling intensity. By identifying these mechanisms, we offer practical guidance for improving surrogate-based biomonitoring. Careful, site-specific selection of surrogate methods is essential to ensure accurate biodiversity assessments.
The plant ionome reflects an interplay between biological requirements and environmental sources, including soil, bedrock, groundwater, and atmospheric dust, as well as factors controlling the bioavailability. Understanding the sources and processes that shape plant ionome is essential for a range of applications, including environmental monitoring, geological mapping, and mineral exploration. The boreal region presents a scenario where the prevalence of allochthonous glacial sediments decouples soil geochemistry from its bedrock source, complicating geological mapping. We investigated the influence of geological and environmental characteristics on the ionomes of Norway spruce, Scots pine, and common juniper in the boreal zone. Samples included bark, twigs, and needles collected from 93 sampling stations across a northern boreal mature forest. Compositional statistical analysis revealed significant effects of edaphic and bedrock properties on conifer ionomes, though responses varied by species and tissue type. Soil moisture and organic matter content strongly influenced cobalt, molybdenum, barium, manganese, but also lead, rubidium, strontium and nickel concentrations. Bedrock geology influenced cobalt, nickel, calcium, magnesium, copper, and lead, detectable even beneath the till cover. A primary challenge lies in determining the specific source for elements originating from both soil and bedrock or mainly one of the sources. Notably, gold‑cobalt mineralisation signals were preserved in Norway spruce bark despite the overlying sediments. These findings demonstrate the utility of conifer ionomes for geological mapping despite complex surficial geology.
In 2024, record high air temperatures were observed in Central and Eastern Europe. Combined with unfavorable precipitation conditions, this caused serious disturbances in forest water resources, which occurred mainly in 2025. These disturbances affected both groundwater and surface water. Groundwater levels reached their lowest points in all forest habitats (fresh, moist, and swampy), indicating a shift in moisture type by one class and reduced water availability for the tree stands. Surface waters in small catchments did not experience any peaks or inundation throughout 2025. In particular, the absence of spring floods severely limited the water supply to riparian habitats. Surface runoff also decreased to about 15% of normal levels. This led to the drying up of significant sections of watercourses, transforming them into intermittent watercourses, and to a substantial reduction in the supply of water to reservoirs on watercourses, resulting in a marked decrease in the amount of water retained and, in some cases, even their complete drying up. Extraordinary phenomena in 2024-2025 may become normal in Eastern Poland in the future.
Intensification of mining has increased the vulnerability of stream ecosystems on the Central African Copperbelt (CACB) to metal pollution. This study assessed the response of microalgae to mining pollution as bioindicators of aquatic ecosystem health in the Upper Kafue River (UKR) on the CACB. Seasonal sampling was conducted at three sites along the UKR: Kafue River Farm (KRF), Hippo Pool (HP), and Mufuchani Bridge (MB). Stream sediment and microalgae samples were analysed for metals. Microalgae were identified morphotaxonomically for relative abundance (pi), Shannon-Wiener diversity (H'), Margalef's richness (M), and Simpson's dominance (D). There were significantly high concentrations in sediment and microalgae, respectively, of Cu (7.04 g/kg; 3.1 mg/kg), Co (214 mg/kg; 0.8 mg/kg), and Pb (68 mg/kg; 0.3 mg/kg) at HP, which also had the highest sediment contamination by Cu (CF = 176) and metal pollution load (PLI = 2.4). However, KRF had the lowest metal concentrations in sediment and microalgae but showed the highest microalgae diversity (H' = 4.0) and taxa richness (M = 5.6). Microalgae genera such as Fragilaria sp. and Closterium sp. were dominant at KRF, while pollution-tolerant species including Microcystis sp. and Volvox sp. were prevalent at HP and MB. Metal bioaccumulation in microalgae was generally higher during the dry season (Cr 0.044-Ni 0.92 mg/kg DW). Principal components analysis confirmed strong correlations between environmental factors and microalgae metrics (p < 0.05). The findings demonstrate the sensitivity of microalgae to site-specific variability in mining pollution, supporting their potential as bioindicators of aquatic ecological health in the CACB and similarly impacted landscapes.
Determining the half-lives of plant protection products and biocides is essential for assessing their environmental persistence and regulatory risk. However, there is no standardized approach defining how many data sets should be considered or whether influencing factors such as substance concentration must be included. For pesticides that are primarily degraded microbially, concentration can significantly influence degradation rates. Elevated levels may exert toxic effects on microorganisms, thereby slowing degradation. This is relevant for the fungicide tebuconazole, which has a broad mode of action including antimicrobial toxicity. Within a comprehensive mesocosm study, concentration-dependent degradation of a commercial tebuconazole formulation was investigated. Eight freshwater stream-pond mesocosms containing flow-through and stagnant zones were established and dosed once with 0, 5, 50, 100, 500, 1000, and 5000 μg/L tebuconazole. Over one year, concentrations in water from all systems and in sediment layers of selected treatments were monitored using GC-MS/MS. Dissipation times for water, sediment, and the overall system were calculated using a newly developed hierarchical kinetic model that incorporated concentration as a covariate, alongside standard degradation models with different error models. A clear concentration dependency was observed: dissipation time increased from 176 days at the lowest concentration to 1079 days at the highest. Transfer to sediment was minimal (<5% within one year). Relevant transformation products were detected and partially quantified in water via LC-MS/MS, but their low quantities allowed them to be excluded from kinetic modeling.
Dung beetles (Coleoptera: Scarabaeoidea) can influence greenhouse gas emissions (GHG) from pasture systems by altering dung decomposition processes. However, the magnitude and direction of the effect of dung beetle presence on dung GHG emissions are not consistent across studies, potentially due to variations in experimental practices. To better understand dung beetles' emission mitigation potential, this study seeks to evaluate how the interactions between dung shape, mass, and dung beetle presence affect dung GHG emissions. A laboratory experiment was conducted to assess the effects of Onthophagus nuchicornis presence, dung shape, and dung mass on dairy cattle dung GHG emissions over a 21-day period. Results revealed that dung mass can significantly impact the effect of dung beetle presence on dung CO2 emissions. The presence of dung beetles in mesocosms containing 100 g dung pats increased CO2 emissions by 29%, while their presence in mesocosms containing the 400 g dung pats increased emissions by 64%. Additionally, the interaction between dung shape and mass, as well as dung shape and beetle presence significantly impacted CH4 emissions. Flattening 100 g dung pats resulted in a 44% reduction in CH4 emissions, while flattening 400 g dung pats reduced CH4 emissions by 13%. Beetle presence in flattened dung pats resulted in a 72% reduction in CH4 emissions, whereas their presence in non-flattened dung pats only resulted in an 8% reduction in CH4 emissions. These findings reveal the importance of methodological decisions when studying the relationship between dung beetle activity and GHG emissions from dung pats.
Ambient particulate pollution in cities may lead to poor indoor air quality in cultural heritage (CH) institutions if preventive actions are not considered and implemented accordingly. This is one of the first studies to propose using technological and biological sensors to monitor both outdoor and indoor environments at CH sites. We studied particulate matter (PM) concentrations in real time using low-cost sensors in three Mexican museums and an archeological zone, where median PM2.5 concentrations exceed the 24-h Air Quality Guidelines level. Leveraging the biological sensor's ability (Tillandsia recurvata) to capture particles, we deployed biomonitoring networks to monitor both outdoor and indoor environments at CH sites over three months and to characterize the magnetic fraction. Micron- and submicron-sized magnetite with spherical and irregular morphologies, co-associated with Cr, Mn, Ni, Cu, and Ba, were detected using magnetic and SEM-EDS techniques. The mean (standard deviation) content of airborne magnetic particles (AMP) decreased from the city center museums to the archeological zone, and from outdoor sites (AMP = 0.12 (0.05) mg) to museums' indoor sites (AMP = 0.06 (0.03) mg). Among urban trees, Ficus benjamina and Fraxinus species were identified as reducing atmospheric particulate matter by retaining it on their leaves; hence, a nature-based solution for preventive conservation in these cultural heritage institutions is proposed.
Plastic production has increased for centuries, with a similar increase in the amount of microplastics released into and accumulating in soils and water bodies, detrimentally affecting organisms. One common transition is via air, during which microplastic particles likely also sediment onto plant parts, e.g., flowers, potentially contaminating floral resources and exposing pollinators to microplastics. In the laboratory, the detrimental effects of such contaminations in sugar water were shown in adult bees, usually honeybees (Apis mellifera), while corresponding experiments with larvae are still scarce. In this study, we tested the effect of pollen contaminated with a microplastics mixture in two concentrations (Low 0.5 mg/kg, High 50 mg/kg) on the development and survival of larvae of two wild bee species (Osmia bicornis and Bombus terrestris). Results indicate that Bombus terrestris larvae fed low microplastic concentrations consumed up to 20% less pollen and developed into significantly fewer pupae (up to 26%) as compared to larvae fed high microplastic concentrations and non-contaminated control pollen. Similarly, Osmia bicornis larvae fed low concentrations of microplastics developed more slowly, hatched later, and showed higher body mass and a higher conversion of pollen to body mass than larvae fed high concentrations of microplastics or the control. Responses differed between treatments and species, suggesting a non-monotonic pattern that warrants confirmation across a broader dose range. A possible explanation might be that higher concentrations activate immune and protective reactions not triggered by lower concentrations. The effects of microplastics on pollinators and other terrestrial organisms clearly warrant further research, as we are only beginning to understand the magnitude of the impacts these pollutants have on our ecosystems.
Urban air pollution may alter plant metabolism long before visible damage becomes apparent. Raman spectroscopy was evaluated as a rapid, non-destructive approach to resolve these biochemical adjustments. Mature Quercus ilex L. trees were sampled along a well-defined pollution gradient in Tuscany (Italy), spanning high, intermediate, and low levels of NO₂ and PM₁₀. Leaf Raman spectra revealed coordinated modulation of primary and secondary metabolism. Pigment-related bands (chlorophylls and carotenoids) increased toward the most polluted site, while inducible flavonoid signals showed site-dependent variation consistent with oxidative pressure in superficial tissues. These patterns were consistent with destructive biochemical analyses and chlorophyll fluorescence measurements, which indicated acclimation rather than photoinhibition damage.A composite Raman index showed a close site-level association with NO₂ exposure, suggesting that nitrogen-related urban pollution was the main exposure component linked to the observed metabolic response.Overall, Raman spectroscopy captures the chronic metabolic imprint of urban air pollution in Q. ilex, resolving coordinated pigment reinforcement and defensive activation without sample destruction. This approach provides a rapid and scalable framework for linking atmospheric chemistry to plant functional status in biomonitoring applications.
Understanding the role of marine vegetation in shaping coastal carbon dynamics and supporting productivity is essential for robust ecological and socio-economic assessments and effective policy development. Our study employed stable isotope analysis (δ13C and δ15N) to investigate the importance of seagrass carbon as a source of nutrition to important invertebrates spanning different trophic levels (i.e., planktonic, filter-feeding and grazing) around the island of Mauritius. Isotope mixing models confirmed high levels of assimilation of seagrass carbon across three trophic levels (dietary proportions ranging from: 35% to 95% for zooplankton, 34% to 59% for the urchin Echinometra mathaei and 14% to 34% for the bivalve Pinna muricata). The degree to which consumers relied on seagrass was strongly influenced by site-specific trends in the relative cover and health of seagrass meadows (i.e., dietary importance declined at sites of observed seagrass loss). Thus, seagrass health is directly implicated in the diet of marine invertebrates, many of which are central to artisanal fisheries and the local blue economy. By integrating novel isotopic data and ecological modelling, we show that seagrass meadows in Mauritius exhibit tight trophic coupling with marine prey species underscoring their importance as engines of nearshore productivity and highlight the urgent need for their protection and restoration across the Western Indian Ocean.
Per- and polyfluoroalkyl substances (PFAS) comprise thousands of anthropogenic fluorinated compounds whose exceptional stability conferred by the carbon-fluorine bond, the strongest single bond in organic chemistry has earned them the epithet "forever chemicals." Decades of use in aqueous film-forming foam (AFFF), industrial processes, and consumer products have created persistent, highly mobile groundwater plumes that are now detected on every inhabited continent. The promulgation of the first legally binding U.S. drinking water limits (4 ng/L for PFOA and PFOS) in 2024, and the regulatory controversy that followed in 2025-2026, have transformed PFAS from an emerging concern into an urgent remediation imperative. This review critically synthesizes contemporary knowledge of PFAS occurrence, geochemical behaviour, and remediation in groundwater, and is organized around a central argument: the field is undergoing a paradigm shift from sequestration to destruction. We first examine sources and subsurface transport, highlighting the physicochemical controls air-water interfacial adsorption, precursor transformation, and matrix interactions that govern plume evolution and complicate site characterization. We then show that the prevailing sequestration technologies (granular activated carbon, ion exchange, and high-pressure membranes) concentrate rather than destroy PFAS, generating problematic residual streams. Against this backdrop, the rapidly developing suite of destruction technologies, electrochemical oxidation, UV/sulfite reductive defluorination by hydrated electrons, supercritical water oxidation, plasma-based treatment, sonolysis, and base-mediated low-temperature mineralization is critically appraised using a common set of criteria: defluorination efficiency, by-product formation, energy demand, and field readiness. A multi-criteria comparison shows that no single technology is superior across all criteria, and that separation and destruction are most rationally deployed as complementary stages of an integrated "concentrate-then-destroy" treatment train. The principal contribution of this review is to place that paradigm on a quantitative footing. We develop a first-order energy model, E_total = E_sep + E_d/CF, which expresses the energy demand of a complete train as a function of the concentration factor CF and thereby reinterprets technology selection in energetic terms. The model yields an explicit design criterion-a technology-specific break-even concentration factor, CF* = E_d/E_sep that identifies how much concentration each destruction route requires before it ceases to dominate the energy budget, and shows that beyond this point the separation step governs whole-train energy. Energy is not the sole determinant of technology choice, and the framework is therefore applied alongside defluorination extent, by-product formation, technology readiness, cost, and matrix compatibility. A simple energy model formalizes this logic, showing that concentration is what renders destruction energetically viable and that, beyond a technology-specific break-even concentration factor, it is the separation step that governs the energy budget of the whole train. We close by identifying priority research needs, including validated destruction metrics, management of short-chain compounds and precursors, and treatment-train optimization. The field's central challenge is no longer removing PFAS from water, but transforming them-cost-effectively and verifiably into harmless fluoride.
The environmental persistence and widespread distribution of per- and polyfluoroalkyl substances (PFAS) are driven by their unique physicochemical properties, including the exceptional strength of carbon‑fluorine (CF) bonds, amphiphilicity, and surface activity, which govern their resistance to degradation, environmental partitioning, and interactions with soil constituents. However, a detailed molecular-level understanding of PFAS sorption on representative mineral surfaces under varying geochemical conditions remains limited. In this study, quartz crystal microbalance with dissipation monitoring (QCM-D) was employed to characterize the sorption behaviors of trifluoroacetic acid (TFA), heptafluorobutyric acid (HFBA), and perfluorooctanoic acid (PFOA) on silicon dioxide (SiO2) and aluminum oxide (Al2O3), two major soil minerals. Sorption on SiO2 was generally weak and primarily governed by hydrophobic interactions, while sorption on Al2O3 was relatively stronger and nonlinear, involving electrostatic attraction between carboxylate groups and positively charged surface sites, and hydrophobic interactions of fluorocarbon chains. PFOA showed the highest sorption affinity, followed by HFBA and TFA. Sorption on SiO2 showed minimal sensitivity to pH and temperature, whereas sorption on Al2O3 decreased markedly with increasing pH and temperature. Divalent cations exerted contrasting effects. On SiO2, Ca2+ and Mg2+ enhanced sorption of long-chain PFAS (PFOA) through cation bridging and reduced electrostatic repulsion, while they suppressed short-chain PFAS (TFA, HFBA). Cu2+ showed a dual effect, promoting PFOA sorption at moderate concentrations but inhibiting it at higher concentrations due to competition for surface sites. On Al2O3, in contrast, all three cations suppressed sorption by compressing the electrical double layer and weakening electrostatic attraction, with the extent varying by chain length. These findings highlight the central role of interfacial processes in controlling PFAS behavior in subsurface environments and provide mechanistic insights that improve the prediction of PFAS fate and mobility, support environmental risk assessment, and guide the development of more effective site-specific remediation strategies for PFAS-contaminated soils and groundwater.
Viruses are common causes of acute gastroenteritis worldwide. They are detected in large quantities in raw sewage making them amenable to wastewater-based surveillance (WBS). To monitor the prevalence of gastroenteritis viruses in wastewater and assess their correlation with clinical cases, wastewater samples collected between July 2020 and June 2024 from 12 wastewater treatment plants across Alberta, Canada were analyzed for norovirus (NoV) GI & GII, rotavirus (RoV), adenovirus (AdV), sapovirus (SaV) and astrovirus (AsV). Among the 5726 wastewater samples tested, AdV (80.5%) had the highest detection rate followed by NoV GII (75.6%), SaV (63.2%), NoV GI (59.4%), RoV (42.2%) and AsV (20.2%). Winter and spring seasonality was found for NoV and RoV in both wastewater and clinical disease. Public health interventions especially in the 1st year of the COVID-19 pandemic had a significant impact on their burden with marked reduction in wastewater detected viruses and clinical cases. NoV showed a strong correlation between its level in wastewater and the number of clinical cases, while moderate correlation was observed for the other four viruses. Cross-correlation analysis showed that changes of viral RNA concentration in wastewater lagged behind reported gastroenteritis cases by approximately 6 days to 3 weeks. To our knowledge, this is the longest multi-region WBS study monitoring multiple gastroenteritis viruses spanning both COVID-19 pandemic and post-pandemic periods. The data obtained from this study supported WBS as a complementary tool to track population-based circulation of gastroenteritis viruses, providing actionable public health data.
The One Health framework, which recognizes the interdependence of human, animal, and ecosystem health, has gained considerable momentum in global health policy. However, its full potential to address health inequities remains underexplored. Environmental justice (EJ), defined by the US EPA as the fair treatment and meaningful involvement of all people regardless of race, color, culture, national origin, income, and educational levels with respect to the development, implementation, and enforcement of protective environmental laws, regulations, and policies, constitutes a natural and necessary complement to One Health. This narrative review examines the conceptual, empirical, and policy interfaces between EJ and One Health, arguing that each framework is incomplete without the other. This review analyzes how socially marginalized populations bear disproportionate environmental burdens through differential exposures to pollutants, zoonotic risks, antimicrobial-resistant pathogens, and the adverse health consequences of climate change. The manuscript also discusses how the One Health approach can be enriched by incorporating EJ principles, including procedural justice, community participation, and the recognition of structural determinants of health. Five guiding principles for integration (namely, structural equity, community-centered participation, epistemic diversity, intersectional vulnerability analysis, and global justice) are proposed, together with concrete recommendations for researchers, policymakers, and international health organizations aiming to build a more equitable One Health governance architecture.
