Search Results (12,451)

This study integrated two surveys—one conducted in August 2021 in the Maowei Sea–Beilun Estuary (14 stations) and another in spring 2023 in Qinzhou Bay (16 stations)—to delineate four functional zones (MWS, BLE, WJ, WW). We systematically analysed zooplankton communities and water quality factors and used Structural Equation Modelling SEM to break down the effects of eutrophication on zooplankton into direct and indirect pathways. The results showed that sixteen zooplankton species belonging to six major taxonomic groups were recorded. Copepoda dominated the community, accounting for 50% of the total recorded species. Parvocalanus crassirostris reached a dominance index (Y) of 0.54, higher than historical records (0.35–0.40), indicating increased community homogenization. Salinity increased from 2.0 to 29.6 psu, resulting in community homogenization, and DIN decreased from 1.282 to 0.19 mg/L. Ei averaged 13.49 (MWS) and 12.80 (BLE). Zooplankton biomass rose nearly 7-fold (125 to 880 mg/m³, p < 0.05). SEM revealed a direct inhibitory pathway from eutrophication (−0.36), an indirect pathway via phytoplankton food-quality degradation (−0.14), and one via community high evenness compression (−0.06), for a total of −0.56 (Bootstrap 95% CI significant). The heavy-metal total effect (−0.18) was much weaker. The SEM fit was excellent (CFI = 0.976, RMSEA = 0.038, R2 = 0.68). This study is the first to quantify dual-indicator management thresholds (salinity < 10 psu and DIN > 0.8 mg/L) for early risk warnings in nearshore aquaculture in this region. Full article

Strigolactones (SLs) have emerged as important regulators of plant adaptation to abiotic stress, functioning not as isolated hormones but as integrative signaling molecules. Beyond stress responses, SLs regulate key biological processes, including shoot branching, root architecture, leaf senescence, nutrient acquisition, rhizosphere communication, flowering-related development, and growth–developmental plasticity. This review synthesizes current knowledge on how SLs modulate plant responses to drought, salinity, heavy metal toxicity, high temperature, and low temperature through crosstalk with abscisic acid, auxin, cytokinin, ethylene, and gibberellin. We examine SL structural diversity, biosynthesis, transport, and signaling together with their roles in growth–stress coordination, hormonal networking, and stress-specific mitigation, while distinguishing endogenous SL functions from responses inferred from exogenous analogs such as GR24. Across stresses, SL-mediated resilience converges on adaptive modules, including water regulation, root–shoot architectural remodeling, redox protection, ion and osmotic homeostasis, photosynthetic maintenance, and rhizosphere-assisted resource acquisition. The mechanistic basis involves transcriptional reprogramming, ROS/RNS-linked redox regulation, metabolic protection, and root–microbe interactions. Translational prospects include SL analogs, genetic manipulation, and breeding for adaptive plasticity, nutrient efficiency, and stress tolerance. However, species specificity, dosage dependence, limited field validation, unclear structure–function relationships, and parasitic-weed stimulation remain major constraints. Full article

Copper is an essential trace element for plant growth; however, in excessive amounts, it can cause severe toxicity by inducing bursts of reactive oxygen species and disrupting metabolic balance. As a root-based medicinal plant and food, Platycodon grandiflorus has its roots in direct contact with the soil. Its ability to accumulate copper is the most pronounced among various heavy metals; consequently, it is particularly susceptible to copper stress, which in turn affects its normal growth and medicinal quality. This paper focuses on the intrinsic stress potential and possible response pathways of Platycodon grandiflorus to copper stress. Drawing on existing research and relevant literature, it conducts an integrated analysis of its defence mechanisms across four levels: physical barriers, non-enzymatic antioxidants, conserved physiological and biochemical pathways, and transcriptional regulation. Regarding physical barriers, the cell wall forms the first line of defence through pectin adsorption and lignin deposition; in terms of endogenous antioxidant defence, secondary metabolites such as polysaccharides and saponins can directly participate in the scavenging of reactive oxygen species; regarding conserved pathways, the glutathione–phytochelate system acts in concert with antioxidant enzymes such as SOD and CAT to participate in copper ion chelation and the alleviation of oxidative stress, with hormone signalling regulation also playing a crucial coordinating role in this process; regarding transcriptional regulation, transcription factors such as PgWRKY may mediate the perception of stress signals and the expression of downstream genes. These pathways act in a coordinated and sequential manner, collectively forming a multi-level defence network through which Platycodon grandiflorus responds to copper stress. At the same time, this paper highlights the functional limitations of this defence system, summarises the shortcomings in current research, and proposes directions for future studies, with a view to guiding the safe cultivation and quality assurance of Platycodon grandiflorus in copper-polluted areas, as well as for the breeding of heavy-metal-tolerant medicinal plants. Full article

This study presents an integrated computational framework for quantifying industrial impacts on marine ecosystems through the combined assessment of multiple environmental quality indices. The Aquatic Water Quality Index (AWQI) and four diagnostic pollution indices, namely the Heavy Metal Pollution Index (HPI), Metal Index (MI), Degree of Contamination (C_d), and Pollution Index (PI), were applied across 23 offshore sites in Mesaieed Industrial City, Qatar, to establish a high-resolution baseline for evaluating the effects of industrial effluents and brine discharge. Multivariate statistical analyses, including Principal Component Analysis (PCA) and Cluster Analysis (CA), identified Cr, Pb, Mn, Ni, and Zn as the principal drivers of water quality variability, effectively distinguishing anthropogenic influences from natural background conditions. To enable rapid and automated marine environmental assessment, three machine learning models—Artificial Neural Networks (ANN), Random Forest (RF), and Decision Trees (DT)—were developed and evaluated for predicting the investigated indices. Model performance was assessed through rigorous training–testing validation and the Diebold–Mariano test. The results demonstrated that model selection significantly influences predictive accuracy. Among the evaluated algorithms, RF achieved the highest predictive performance for AWQI (R² = 0.88) and C_d (R² = 0.92), whereas ANN performed best for HPI (R² = 0.89), and DT yielded the most accurate predictions for MI (R² = 0.82). Despite the index-specific strengths of individual models, RF emerged as the most robust and generalizable approach, consistently providing superior performance across heterogeneous environmental datasets. The proposed framework advances marine water quality assessment from conventional descriptive monitoring toward a proactive, data-driven paradigm, offering a scalable and cost-effective decision support tool for environmental management, pollution mitigation, and evidence-based coastal governance in industrialized coastal regions. Full article

Table olive processing comprises multiple stages in which physical, chemical, and biological hazards may occur. Although risk assessment is a core element of Hazard Analysis and Critical Control Points (HACCP) systems, the selection of assessment tools remains insufficiently standardized. This study compared a 4 × 4 risk matrix and Failure Mode and Effects Analysis (FMEA) for hazard evaluation in Spanish-style and Californian-style table olive processing. Hazards were assessed across 41 processing stages for Spanish-style olives and selected key stages for Californian-style olives using probability × severity in the 4 × 4 matrix and severity × occurrence × detection in FMEA. Significant hazards were further evaluated using the Codex Alimentarius decision tree to identify critical control points (CCPs) and strengthened prerequisite programs (PRPs). Both tools identified similar significant hazards, including biological hazards associated with fermentation, brine management, storage, container sealing, and heat treatment, as well as physical hazards from foreign bodies and chemical hazards related to heavy metals, pesticide residues, mycotoxins, and food-contact material migration. FMEA provided greater analytical detail through the detection parameter, whereas the 4 × 4 matrix was simpler and more practical for complex flow diagrams. Overall, both tools were suitable for HACCP-based risk assessment in table olive processing. Full article

This study focuses on the design and development of the Double Purpose Bench Vise to address safety, efficiency, and adaptability challenges in welding and fabrication environments. The project responds to limitations of conventional vises that restrict precision and increase the risk of strain-related injuries when handling heavy, irregular, or vertically oriented workpieces. Through an engineering-based development approach involving analysis, design, fabrication, and performance evaluation, the study introduces a Double Jaw Vertical Bench Vise equipped with a dual-clamping system and an integrated hydraulic jack mechanism for precise vertical adjustment with minimal physical effort. The device is designed to securely hold various materials, including metal bars, pipes, and wooden components, during cutting, grinding, shaping, welding, and assembly operations. Evaluation results from functional testing and user feedback indicate improved clamping stability, alignment accuracy, and ergonomic performance compared to traditional models, although refinements in structural optimization, weight distribution, and user interface components are recommended. The study suggests further prototype enhancement, extended field testing, and integration of advanced ergonomic and safety features to maximize durability, usability, and overall productivity in professional workshops and technical training laboratories. Full article

The production of inexpensive, effective sorbents from natural materials for the purification of water bodies and/or soils is a pressing problem. Therefore, the purpose of this manuscript is to summarize current approaches to the use of brown coal (lignite) and its processing products (humic acids, HAs) as sorbents for the purification of aqueous and soil environments from heavy metal ions and other pollutants. Modification of lignite (chemical, biological, physicochemical) or the creation of lignite–mineral composites significantly increases its sorption capacity and stability: after modification, the sorption capacity can reach more than 85 mg of heavy metals per g of sorbent, which is only 3 times lower than that of specialized, expensive sorbents. Also, good results are achieved in the case of sorption of water-soluble organic drugs, dyes, etc. Humic acids obtained from brown coal have better selectivity and efficiency than the original lignite, and slightly worse than the modified one, in terms of removing cadmium, lead, copper, and other toxic elements; and also, can complex with organic xenobiotics. Current research trends indicate growing interest in multifunctional composite sorbents, environmentally friendly extraction technologies, and the development of materials with enhanced selectivity and regeneration ability. Future studies should focus on improving the understanding of sorption mechanisms, optimizing modification strategies, scaling up lignite-based technologies for practical environmental applications, and developing waste-free technologies to produce sorbents from lignite. Full article

Conventional sterilization methods limit smallholder mushroom cultivation in PNG. This study evaluated alternative disinfection approaches for Pleurotus ostreatus (P. ostreatus) using coffee parchment and Cenchrus fungiraminus (C. fungigraminus) as substrates. After screening 20 strains, the superior strain PXF9 was selected. Three methods were compared: (1) Complete Sterilization with Aseptic Inoculation (CSAI) applied to T1 (experimental) and T2 (sawdust control); (2) Short Sterilization with Open Inoculation (SSOI) applied to T3 (experimental) and T5 (control); and (3) Non sterilization with Open Inoculation (NSOI) applied to T4 (experimental). CSAI (T1) achieved the highest yield (3985.26 ± 2.00 ^d g/24 bags), biological efficiency (83.03%), protein (28.44 g/100 g), and profit (14.76 USD), with the fastest colonization (21 days). SSOI (T3) produced the largest fruiting bodies; NSOI (T4) had the lowest heavy metal levels. SSOI and NSOI were economically beneficial (9.88 and 5.96 UDS per 24 bags). Bioactive compounds (e.g., naringenin, ergosterol peroxide), were detected across treatments. While CSAI maximizes productivity, SSOI and NSOI offer low-cost alternatives for resource-limited farmers. Full article

The environmental impacts of treated acid mine drainage on receiving river systems remain insufficiently understood. This study investigated four typical closed coal mines in northern Sichuan Province, China, by analyzing heavy metals, sulfate, pH, UV-Vis spectroscopy, and dissolved organic matter (DOM) characteristics at 24 sampling sites along the receiving reaches. Parallel factor analysis (PARAFAC) and two-dimensional correlation spectroscopy (2D-COS) were employed to examine the longitudinal response sequence of DOM components. Results showed that pollutant concentrations generally increased immediately after the inflow of treated acid mine drainage and then progressively attenuated downstream, although the dominant pollution factors varied significantly among the reaches. DOM composition exhibited spatial heterogeneity, with protein-like components dominating three reaches and humic-like components prevailing in one reach. Based on the co-variation characteristics of DOM and heavy metals along the river course, four response patterns were identified: rapid-recovery, slow-recovery, disturbance–oscillation recovery, and delayed-recovery patterns. The 2D-COS analysis validated the rationality of these four patterns and revealed differences in the sensitivity of various DOM components to longitudinal disturbances. This study provides a scientific basis for the environmental impact assessment of mine water from remediated closed coal mines. Full article

In the Iberian Pyrite Belt (IPB), long-term persistence of mine waste piles poses environmental challenges. The present work studies the Trimpancho Mining Complex in northern IPB with exposed mine waste and acidic waters in the proximity to the Chança River, a tributary of the Guadiana international river. A multidisciplinary approach is proposed, using hyperspectral reflectance spectroscopy, portable X-ray fluorescence (pXRF), multispectral Unmanned Aerial Vehicle (UAV) and Sentinel-2 images. Spectroscopic, geochemical and remote sensing methods were applied to characterise the mining area. Comparison of hyperspectral data with spectral libraries were used to validate mineralogy. Multispectral UAV data is used for custom band-ratios and adapted to Sentinel-2 images. Results grouped the samples into four groups. Spectroscopy is indicative of clays (white mica and smectite group), hematite/goethite, jarosite, and arsenopyrite and pyrite (exclusive to the Group 2); iron-rich samples reach maximum reflectance earlier than iron-poor samples. Geochemical studies show an increase in content of heavy metal such as As, Cu, Fe, Pb, and Zn from Group 1 < Group 3 ≈ Group 4 < Group 2, but Group 4 showed elevated Pb and Zn. Custom false colour composition highlighted the groups in UAV and satellite, thus constituting cost-effective tools for finding contamination sources. Full article

Gold-mine tailings have attracted increasing interest as alternative constituents in cement-based materials, yet their use in structural concrete remains limited by the lack of multivariable approaches capable of capturing the interaction between tailing fractions with different functional roles. In this study, a tailing-derived fine aggregate and a fine tailing sludge from the Cisneros Project (Santo Domingo, Antioquia, Colombia) were jointly incorporated into structural concrete and evaluated through a response surface methodology based on a central composite design. The tailings were characterized by physical, chemical, mineralogical, and morphological analyses, while concrete mixtures proportioned according to ACI 211 were assessed in terms of 28-day compressive strength. The statistical model revealed a significant quadratic response and a strong interaction between both incorporation variables. The most favorable strength region, based solely on 28-day compressive strength, was identified at sludge contents below 20% and tailing aggregate replacement below 90%, with the latter interpreted as a preliminary mechanical threshold rather than as a practical recommendation for field application. Higher incorporation levels led to strength losses associated with the increasing fineness of the system and greater water demand. This study demonstrates that the performance of tailing-modified structural concrete depends on the coordinated dosage of fractions with distinct roles and provides preliminary mechanical incorporation limits based solely on 28-day compressive strength. Since durability and environmental safety tests, including heavy metal/cyanide leaching, permeability, shrinkage, and chemical resistance, were not conducted, these limits should not be interpreted as definitive recommendations for long-term structural application. Full article

The sustainability, crop production, and food safety of agriculture are increasingly challenged by microplastic pollution, as agricultural soils are the largest reservoirs and may serve as points of contact for plastic particles in the food chain. This review provides a comprehensive overview of plant materials, fate and uptake pathways, detection techniques, and the possible risks of microplastics in agriculture. Agroecosystems are also a source of microplastics, such as plastic mulch films, sewage sludge, compost and manure additives, wastewater irrigation, polymer-coated fertilizers, greenhouse materials, atmospheric deposition, and decomposition of discarded agricultural plastics. Their distribution and mobility in soil are controlled by polymer composition, particle size, morphology, density, surface ageing, soil texture, organic matter content, tillage practices, runoff, leaching, and soil biota. Recent data show that microplastics, especially smaller microplastics and nanoplastics, can attach to root surfaces, penetrate plants via cracks in roots, areas of lateral root development, and apoplastic pathways, and eventually move to tissues aboveground. Plant tissue detection is often accomplished by digestion of the sample, density separation, visual and fluorescence microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, pyrolysis–gas chromatography mass spectrometry, and electron microscopy, but standardization of these methods remains a significant challenge. Microplastics can disrupt seed germination, root structure, nutrient absorption, photosynthesis, oxidative homeostasis, biomass buildup, yield development, and quality. Further, their capacity to transport additives, plasticizers, heavy metals, and persistent organic pollutants raises concerns about the transfer of contaminants to edible plant parts and their potential transfer to human diets. Further studies are needed focusing on field-realistic exposure conditions, long-term crop–soil interactions, nanoplastics behaviour, standardised analysis procedures, uptake and translocation pathways, edible crop risk assessments, and sustainable mitigation approaches to reduce microplastics in agroecosystems. Full article

Sunflower (Helianthus annuus) can potentially be used for uranium (U) phytoremediation. However, the influence of arbuscular mycorrhizal fungi (AMF) on key rhizosphere processes and plant U uptake remains insufficiently researched. We hypothesized that AMF inoculation could enhance sunflower tolerance to U stress by improving plant physiological performance and modifying rhizosphere properties. To test this hypothesis, this study examined the effects of AMF (Funneliformis mosseae, Glomus etunicatum, and their co-inoculation) on sunflowers under U stress, encompassing plant growth and physiological traits, rhizosphere properties, enzyme activities in the rhizosphere soil, uranium speciation in the rhizosphere soil, and the accumulation and distribution of uranium within the plant. Results showed that AMF successfully colonized the roots, enhancing plant growth, biomass, and gas exchange, while improving photosynthetic efficiency and reducing non-photochemical quenching. In the rhizosphere, AMF elevated soil respiration, organic matter, dissolved organic carbon, and microbial biomass carbon; improved phosphatases, urease, catalase, and sucrase activities; also reshaped U speciation, increasing exchangeable and carbonate-bound fractions while decreasing those bound to organic matter, Fe/Mn oxides, and residual phases. Moreover, AMF reduced U concentration in leaves and stems, promoted U retention in belowground tissues, and significantly lowered the U translocation factor. These findings demonstrate that AMF inoculation improves sunflower tolerance to U stress by enhancing physiological performance, modifying rhizosphere properties, and immobilizing U in roots, supporting its potential use in phytoremediation strategies for U-contaminated environments. Full article

The aim of this study was to critically assess the usefulness of pollution indicators in monitoring riverside soils (fluvisols) for heavy metal content. A novel methodological approach was used, comparing areas located inside and outside flood embankments, which allowed for a precise determination of the impact of fluvial and anthropogenic processes on heavy metal accumulation. The experimental logic validated the usefulness of four indicators: the Individual Pollutant Index (PI), the Background Enrichment Factor (PIN), the Potential Ecological Risk (RI), and the Pollution Load Index (PLI). Comparative analysis revealed that soils within the embankment zone have higher metal concentrations, resulting from the continuous deposition of alluvial material, which often contains industrial and municipal pollutants. The vertical distribution of pollutants in fluvisols was shown to be closely related to sediment dynamics and soil properties (clay fraction, organic matter, redox conditions). Validation of the indicators revealed their varying sensitivity. The study revealed the limitations of the PLI, which, due to its summary nature, did not account for significant variability in contamination within the soil profile. Consequently, the PI, PIN, and RI indices were shown to be the most effective tools in assessing the actual degree of soil contamination by fluvisols in the middle Oder Valley. The study results emphasise the need for the selective selection of indicators in environmental monitoring. This comparative approach provides a reliable method for assessing the effectiveness of floodplain management strategies under exposure to chemical pressure. Full article

The karst region of Southwest China represents a typical high geological background area characterized by extensive carbonate bedrock and secondary enrichment of heavy metals, particularly cadmium (Cd), in residual soils. Under natural carbonate-buffered conditions, Cd is largely immobilized through mineral associations and surface complexation, resulting in elevated total concentrations but low bioavailability. However, intensified anthropogenic pressures–including acid deposition, mining, excessive fertilization, and improper irrigation—have accelerated soil acidification in paddy fields. Acidification disrupts carbonate geochemical equilibria, weakens buffering capacity, and drives Cd speciation shifts toward more labile forms, thereby enhancing plant uptake and accumulation. These effects are especially pronounced in paddy fields and other systems subject to hydrological and redox fluctuations that further increase Cd mobility. To evaluate these coupled geogenic and anthropogenic controls, we conducted a structured literature synthesis (2016–2026) focusing on peer-reviewed studies of Cd dynamics in Southwestern China’s karst agroecosystems. We critically examine (i) the formation mechanisms and spatial heterogeneity of high-background Cd, (ii) acidification-driven speciation transformation and soil–crop transfer pathways, and (iii) in situ remediation and precision risk assessment strategies. By integrating geological inheritance, geochemical activation, and ecological risk perspectives, this review proposes a conceptual framework to support soil quality standard refinement and adaptive risk management in high-background karst regions. Full article