Search Results (9,794)

Heavy metal contamination in agricultural soils threatens ecosystem safety and sustainable land use, particularly in geologically sensitive areas. This study aimed to assess the pollution status, ecological risks and source contributions of eight heavy metals (Hg, Cd, Pb, As, Cr, Cu, Ni and Zn) in soils from a dry-hot agricultural region of central Yunnan, China. To improve source apportionment, this study applied and compared three models: APCS-MLR, PMF, and Random Forest. Analysis of 1790 soil samples showed mean concentrations (mg/kg) of 0.03 for Hg, 0.17 for Cd, 25.01 for Pb, 7.46 for As, 85.91 for Cr, 36.20 for Cu, 31.75 for Ni, and 69.24 for Zn. Pollution assessment indicated that Cu and Cd were the main pollutants, while ecological risk assessment identified Cd and Hg as the dominant ecological risk factors. Four major sources were identified: industrial hybrid sources, natural background, atmospheric deposition and agricultural activities, with industrial hybrid sources contributing the largest share. These results indicate that integrating APCS-MLR, PMF, and Random Forest provides a more reliable framework for source identification and supports targeted soil pollution control in regions affected by both natural and anthropogenic inputs. Full article

The increasing integration of nonlinear loads in modern power systems has made harmonic pollution a critical challenge to the operational safety of power cables. This study develops a frequency-dependent high-voltage cable system model using the ATP-EMTP (Alternative Transients Program-Electro Magnetic Transient Program) electromagnetic transient simulation platform, systematically investigating the amplification mechanisms and propagation characteristics of grounding currents under multi-type harmonic disturbances. A frequency-dependent parameter correction model is established by integrating the conductor skin effect and the dielectric relaxation properties of the insulation layers. This model incorporates the multi-structure combination among conductors, insulation, and metallic screen. It effectively overcomes the limitations of conventional lumped-parameter models in higher frequency harmonic analysis. Key findings are as follows: (1) The combined influence of harmonic frequency and amplitude leads to a grounding current amplification of up to 445 times (at 1950 Hz with 30% distortion level). Notably, current-source excitation produces significantly greater amplification than voltage-source excitation. (2) The distributed capacitance of long-distance cables (>8 km) exacerbates resonance risks within specific frequency bands (750–1250 Hz), resulting in a maximum harmonic amplification factor of 34.73 (observed for the 17th harmonic in a 15 km cable). (3) The contribution of voltage-source harmonics diminishes to less than 5% of the total current at high frequencies (≥1250 Hz), indicating a pattern of current-dominated harmonic superposition. Full article

Accurate forecasting of near-surface PM_2.5 concentrations remains challenging due to the complex coupling between atmospheric vertical structure, thermodynamic stability, and pollutant accumulation processes. Most existing surface-based statistical and deep learning approaches struggle to represent the three-dimensional state of the atmosphere, which limits their robustness under complex meteorological conditions. In this study, we propose a multi-source spatiotemporal learning framework(MST-Net) to enhance PM_2.5 forecasting accuracy by integrating vertically resolved atmospheric information from lidar and radiosonde observations. The proposed approach incorporates vertical profile features together with surface measurements to provide complementary information on atmospheric vertical structure and its temporal evolution. Experimental results demonstrate that MST-Net consistently outperforms conventional time-series models across multiple forecast horizons. Notably, at extended lead times (12–24 h), the proposed framework exhibits enhanced stability and slower error growth. For 24 h forecasts, MST-Net reduces RMSE by approximately 13% and MAE by about 19%. These results indicate that leveraging multi-source vertical atmospheric information can effectively improve the reliability of urban air quality forecasting. Full article

This research focuses on the synthesis of a novel baking powder enriched with bioactive molecules recovered from olive pomace via ultrasound-assisted extraction using a hydro-ethanolic mixture. The functional ingredient was engineered by anchoring the extracted phytocompounds onto a starch backbone through a sustainable grafting technique. Biscuits formulated with the innovative ingredient showed an increased concentration of phenolic compounds (2.162 mg GAE/g), encompassing both phenolic acids (0.372 mg GAE/g) and flavonoids (0.360 mg CTE/g). Enhanced antioxidant efficacy was recorded, mostly in aqueous media (IC₅₀ = 0.554 mg mL⁻¹ against ABTS radical) compared to organic environments (IC₅₀ = 0.132 mg mL⁻¹ against DPPH radical). Furthermore, Oxitest and oxidation stability reactor analyses revealed exceptional antioxidant capacity (induction period = 37 ± 2 h). By an accelerated shelf-life test, a marked instrumental color difference was observed with the fortified sample showing a darker, redder/brown color (ΔE > 16), as also confirmed by trained panelists. On the contrary, similar scores were achieved for the olfactory, textural and tasting attributes of the two samples, as well as values of the friability index (<1 mm⁻¹) evaluated by instrumental techniques. This approach represents a sustainable strategy, transforming a high-polluting agri-food by-product into a source of bioactive compounds for nutritional and technological improvement of baked foods. Full article

Bioaerosol emissions from biological treatment processes like composting, livestock operations, and wastewater plants pose notable occupational and environmental health risks. Biofiltration is a common mitigation measure for gaseous pollutants, but its effectiveness in controlling bioaerosols is less studied. This review synthesizes current evidence on biofiltration for the removal of bioaerosols. Findings indicate that biofiltration can significantly reduce emissions from waste-related biological processes, although results vary widely and depend heavily on design and operational factors. In composting, agricultural, and wastewater treatment contexts, fungal bioaerosols are consistently removed with high efficiency, often over 90%. Conversely, bacterial removal shows greater variability, from negligible to above 90%, influenced primarily by airflow rate, bed depth, and media stability. Systems with residence times of tens of seconds and bed depths of at least 1 m tend to reliably reduce bacterial counts, whereas undersized, high-flow systems experience marked efficiency losses. The choice of packing material is also crucial; mature, stable media maintain performance, whereas nutrient-rich or unstable substrates can lead to fungal emissions, turning the biofilter into a secondary source. Data on endotoxin removal are limited and remain insufficient for firm design recommendations. Overall, biofiltration’s effectiveness depends on complex interactions among physical retention, biological stability, and design. These insights emphasize the need for future research to focus on standardized, performance-based design criteria supported by consistent reporting and full-scale validation. Full article

Accurate, high-resolution emission inventories are essential for air quality modeling and policy evaluation, yet national-scale inventories for Thailand remain limited in spatial and temporal detail. This study develops a comprehensive national emission inventory for Thailand in 2019 (EI–TH 2019), covering 12 major air pollutants and greenhouse gases across key sectors, including energy, transport, industry, agriculture, waste, and residential activities. The inventory is constructed using country-specific activity data from official statistics and sectoral surveys, combined with GAINS-consistent emission factors and control assumptions. Emissions are resolved at 1 × 1 km spatial resolution and monthly temporal resolution to capture Thailand-specific emission dynamics. The results show that emissions across major pollutants are dominated by a limited number of source groups, with biomass burning and residential solid-fuel use driving particulate matter, transport dominating NO_x and CO emissions, large-scale combustion and industry controlling SO₂ emissions, and agriculture contributing the majority of NH₃ emissions. Strong seasonal variability is observed in PM_2.5, CO, and NH₃, primarily driven by dry-season biomass burning, whereas NO_x and SO₂ exhibit relatively stable temporal patterns. The reliability of EI–TH 2019 is supported by a multi-dimensional evaluation framework. Temporal consistency is demonstrated through strong agreement between modeled PM_2.5 emissions and ground-based observations, as well as between NO_x emissions and satellite-derived TROPOMI NO₂ (r = 0.93; ρ = 0.96). Biomass burning timing is further validated using satellite fire activity (VIIRS), showing consistent seasonal patterns. Comparisons with global inventories (EDGAR v8.1, HTAP v3.2, and GFED5.1) reveal systematic differences in sectoral contributions, temporal profiles, and emission magnitudes, particularly for biomass burning, reflecting the importance of country-specific data and assumptions. Overall, EI–TH 2019 provides a robust, high-resolution, and policy-relevant emission dataset that improves the representation of emission processes in Thailand. The results highlight key priority sectors—biomass burning, transport, industry, and agriculture—for targeted emission-reduction strategies and support applications in chemical transport modeling, exposure assessment, and integrated air-quality and climate-policy analysis. Full article

To comprehensively investigate the aerosol optical properties and vertical structures over the northeastern Tibetan Plateau (TP), a field campaign was conducted from January to August 2023 in the Hainan Tibetan Autonomous Prefecture. Ground-based sunphotometer measurements yielded a mean aerosol optical depth (AOD) of 0.18 and an Ångström exponent (AE) of 1.20 over the study period. The lowest AE, observed in April alongside the highest aerosol loading, suggests a predominance of dust aerosols during this period. This finding is further supported by the elevated vertical extinction profiles derived from LiDAR measurements, indicating long-range transboundary transport of dust aerosols from northern desert regions. Ground-based AOD measurements were used to validate satellite-derived MODIS retrievals and the assimilated MERRA-2 reanalysis product. Among the aerosol types examined, dust aerosols exhibited the highest accuracy in both AOD and AE validation. MERRA-2 was found to systematically underestimate AOD by 22% and AE by 35%. Nevertheless, due to its tighter expected error envelope, lower overall errors, and superior temporal continuity and spatial coverage, MERRA-2 remains a reliable data source for subsequent analyses. A long-term analysis spanning 2006 to 2025 identifies 2011 as a turning point, after which AOD declined at a rate of 0.0022 per year. This sustained reduction highlights the effectiveness of China’s air pollution prevention and control policies. Collectively, these findings provide essential insights for refining satellite retrieval algorithms and aerosol–climate models over the TP. Full article

To address ship-sourced water pollutant issues resulting from shipping industry growth and achieve precise supervision and effective management in coastal ports, this study develops a method for calculating and predicting the generation volume of oily sewage, domestic sewage and solid waste based on Automatic Identification System (AIS) data. First, a questionnaire survey (“Survey on Ship Water Pollutants”) is designed and implemented. Through analysis of questionnaire data, the ranges of values for the generation of oily sewage, domestic sewage, and solid waste from different ship types at China’s coastal ports are established. Additionally, onboard sampling is conducted to determine average emission factors for domestic sewage and oily sewage from typical ship types. Second, ship activities are derived from AIS data and combined with the established generation volume ranges for spatiotemporal calculation. Finally, a ConvLSTM (Convolutional Long Short-Term Memory) model is developed to predict the generation volume of water pollutant based on their spatiotemporal characteristics. Taking a major Chinese port area as a case study, the results indicate that pollutant generation volumes are significant in coastal port zones and main navigation channels, particularly between 15:00 and 16:00. chemical oxygen demand (COD), suspended solids (SS), and 5-day biochemical oxygen demand (BOD₅) levels in domestic sewage exceeded China’s national regulatory limits by 0.35 times, 2.88 times and 1.07 times, respectively, which can easily lead to a decrease in dissolved oxygen content in the water, affecting the respiration and survival of aquatic organisms. Petroleum content in oily sewage remained below the standard threshold. For pollutant generation volume prediction, the proposed ConvLSTM model achieved MAE and RMSE values of 0.0824 and 0.1433, respectively, outperforming other prediction models such as LSTM and CNN-LSTM. This research provides technical support for the prevention and control of water pollution from ships in coastal ports. The proposed AIS-driven framework and ConvLSTM prediction method are transferable and globally applicable, offering a reference for the environmental sustainability of port ecosystems, the global maritime pollution prevention, and the sustainable development of the shipping industry worldwide. Full article

Fugitive greenhouse gas (GHG) emissions in industrial parks are characterized by high opacity and spatial dispersion. Existing localization and quantification methods often rely on idealized meteorological assumptions and low-precision mobile monitoring data, making it difficult to achieve accurate source characterization. This study focuses on the Nansha Economic and Technological Development Zone in Guangzhou—one of the first pilot zones for synergistic pollution and carbon reduction in China—to develop an atmospheric inversion model based on multi-site fixed monitoring. By integrating GHG concentrations with multi-dimensional meteorological parameters, the model couples an atmospheric dispersion framework with a Bayesian inversion algorithm. Specifically, site-specific conditions and high-frequency meteorological data are utilized to constrain dispersion parameters, effectively reducing model uncertainty driven by meteorological variability. Within the Bayesian framework, the model enables the simultaneous inversion of both the locations and emission strengths of multiple sources. Results identified three distinct fugitive emission sources: one primary source in the International Auto Industrial Park with a CO₂ emission intensity of 103.15 g/s and two sources in the Western Industrial Park with intensities of 0.051 g/s and 0.26 g/s, respectively. Overall, this research framework significantly enhances the accuracy and spatial resolution of emission inversion, providing robust technical support for precision carbon management and the development of targeted mitigation strategies for key industrial processes. Full article

Nanoparticles (NPs) of urban dust can be hazardous to human health due to the possibility of a high accumulation of potentially toxic elements (PTEs), high penetration ability into organisms, and their ability to cause injury to cells, tissues, and organs. The composition of NPs of urban dust may vary during the year; however, there are so far no studies on the seasonal changes in their elemental composition and related ecological and health risks. The current work was carried out using samples of urban dust from Moscow, the largest megacity in Europe, collected in spring, summer, and autumn. It was found that NPs of urban dust are polluted by PTEs, namely W, Bi, Hg, P, S, Sn, Mo, Cu, Cd, Pb, Sb, and Zn. The highest pollution and ecological risks were found in NPs of urban dust collected in summer (RI = 592) as compared to autumn (RI = 399) and spring (RI = 231). The same regularity was observed for health risks. The highest possible cancerogenic risk was found in summer NPs (CTCR = 3.0 × 10⁻⁴) followed by autumn NPs (CTCR = 2.5 × 10⁻⁴) and spring NPs (CTCR = 3.5 × 10⁻⁵). However, the difference between mean values obtained for the three seasons was not statistically significant. Additionally, it was demonstrated that vehicle emissions are one of the main sources of pollution of NPs, and their intensity does not significantly change throughout the year in Moscow. The results obtained offer new insights into the regularities of seasonal variations in elemental composition, pollution, and related ecological and health risks of NPs of urban dust. Full article

This paper addresses the issue of lighting in historic urban spaces, using Tarnow (Poland) as a case study. The aim is to assess the impact of artificial light sources on visual comfort within the area, with particular consideration given to light pollution. A comprehensive inventory of active street lighting in the Old Town was conducted. Measurements taken at ground and eye level revealed strong inconsistencies: some areas were under-lit (<1 lx), while others showed façade illuminance above 100 lx, far exceeding recommended thresholds. The highest environmental impact was shown by decorative and globe-type fixtures, with Sky Glow Contribution Index (SGCI) values of up to 0.62. Only suspended street luminaires met CIE requirements (ULR ≤ 15%). The findings reveal that several lighting installations do not meet recommended standards, adversely affecting both human comfort and ecological balance. The study proposes strategies to optimise urban lighting, such as replacing inefficient fixtures with full cut-off LED luminaires and implementing intelligent lighting control systems which could reduce energy consumption by 50-67% while preserving the architectural character of the historic centre. The results provide evidence-based strategies for sustainable lighting modernisation in heritage cities across Europe. Full article

Despite stringent national clean air policies, severe PM_2.5 and ozone (O₃) pollution persists in some parts of China, notably the Sichuan Basin—a key economic zone in the southwest. High-resolution assessment of the health and crop impacts of these pollutants remains limited in this region. In this study, we developed a multi-source data fusion framework based on a machine learning model to reconstruct daily PM_2.5 and O₃ concentrations at 1 km resolution during 2015–2021. The model integrates ground observations, meteorological data, chemical transport model outputs, and satellite retrievals. The model performed robustly, achieving R² values of 0.91 for PM_2.5 and 0.64 for O₃. PM_2.5 exhibited a decreasing tendency after 2017, while O₃ showed interannual variability, with peaks in 2016 and 2018. Spatially, PM_2.5 was more concentrated in urban centers, whereas O₃ showed higher levels in western Sichuan and a banded pattern in the east. Seasonal patterns were also evident: PM_2.5 increased in autumn and winter due to meteorological and emission factors, while O₃ peaked in spring and summer, driven by photochemistry and high temperatures. Topography and emissions further shaped these distributions, with mountains in the west trapping O₃ and urban clusters exacerbating PM_2.5. Based on the reconstructed dataset, we further explored the potential impacts of pollutant exposure on human health and crop yields. The results provide a high-resolution dataset for understanding pollutant variability. Full article

Adobe is a sustainable yet highly porous construction material, inherently vulnerable to moisture and environmental pollution, which poses challenges for both contemporary construction and heritage conservation. This study presents multifunctional coatings that combine hydrophobic/oleophobic and photocatalytic properties to enhance adobe durability. The coatings incorporate nano-heterostructured LaFeO₃ photocatalysts into water-repellent and hydro-oleo-repellent formulations, selected to preserve the characteristic dark brown color of adobe. Microstructural analyses revealed the formation of non-uniform protective layers, particularly in hydro-oleo-repellent systems, which influenced performance. The treated surfaces exhibited significant water and oil repellency, while maintaining adequate vapor permeability. Durability tests confirmed improved resistance to water ingress, reduced capillary absorption, and enhanced erosion resistance compared to untreated adobe. Sustainability assessments highlighted the environmental and economic benefits of the proposed approach, especially when using locally sourced materials. Overall, this work proposes a scalable and multifunctional strategy that integrates protective and photocatalytic functionalities to extend the service life of both historical and modern adobe structures. Full article

Groundwater in uranium mining areas is highly sensitive to pollution by radionuclides and toxic elements, especially under in situ leaching mining, which increases their mobility. This study assesses the radiological and chemical features of water sources in the Chu-Sarysu uranium province (Kazakhstan) by evaluating the annual effective dose (AED) from radionuclide ingestion. In total, 98 water samples from boreholes, wells and rivers were analyzed for total alpha and beta activity, followed by radionuclide and chemical analysis of selected samples. High total alpha activity was detected mainly in groundwater and was associated with radium mobilization. On average, ²²⁸Ra constituted between 50% and 60% of the total AED, whereas ²²⁶Ra contributed between 35% and 45%, with uranium isotopes contributing less than 5%. The total AED value for the groundwater ranged from 0.14 to 0.52 mSv/year at average water use, but only one borehole sample had 9.07 mSv/year, reflecting a localized anomaly. Additionally, arsenic, manganese, and mercury displayed high spatial variability. These findings underscore radium’s significant role in radiation exposure and emphasize the need for comprehensive monitoring of both radiological and chemical contaminants in groundwater systems. Full article

Freshwater scarcity is a major global issue faced by various regions, and the most common portable water sources globally are estuaries, canals, dams, lakes, and rivers. Existing water resources function as the best sinks for the frequent release of effluents from industrial and residential activities. This common practice often results in water pollution, a deterioration in marine biodiversity, and possible health risks for human populations. This study employed standard analytical methods in assessing the physicochemical and microbial characteristics of water samples collected from the Sundays River estuary in Eastern Cape Province (ECP), South Africa (SA). Microbiological assessment revealed that during the spring season, presumptive Escherichia coli (E. coli) colony counts were 1 cfu/100 mL, while total coliforms (TCs) and fecal coliforms (FCs) were recorded at 42.67 cfu/100 mL and 1 cfu/100 mL, respectively. In the summer season, fecal coliform (FC) counts reached 3.5 cfu/100 mL, while Enterococcus levels were higher, ranging up to 77.75 cfu/100 mL. Furthermore, the average standards of physicochemical parameters assessed in water obtained from both spring and summer seasons ranged as follows: pH (8.71–9.31), temperature (20.98–22.21 °C), turbidity (10–35.55 FNU), total alkalinity (22.25–94.00 mg/L), oxidation–reduction potential (ORP) (8.05–151.6 mV), electrical conductivity (EC) (13,915–40,260 uS/cm), salinity (8.07–25.78 psu), dissolved oxygen (DO) (6.79–7.39 mg/L), total dissolved solids (TDSs) (6960.6–20,125 mg/L), and biochemical oxygen demand (BOD) (0.11–2.94 mg/L). The levels of TDS, EC, turbidity, and salinity in the Sundays River estuary water exceeded the World Health Organization (WHO) guidelines of 2017, rendering the water unfit for even recreational purposes. Additionally, the bacterial levels identified in this study were above the values set by the South Africa Department of Water Affairs (SA-DWAF). The identified microorganisms are perceived as essential indicators of fecal contamination and have the potential to multiply in the environment. Possible pollution may be a result of various municipal effluents consistently discharged into the waterbody. Full article