Water, Air, & Soil Pollution最新文献

Understanding how hydroclimatic (HC) and land use and land cover (LULC) variabilities affect surface water quality is very important for effective water resources management. In this study, seven water quality parameters were analyzed in four watersheds in the city of Fortaleza, the Brazilian capital with the highest population density: biochemical oxygen demand (BOD), chlorophyll-a (Chl-a), dissolved oxygen (DO), total coliforms (TC), total nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS). Data were grouped into two periods: the wet period (January to June) and the dry period (July to December). The results showed that intra-annual variability of precipitation and land use/cover had a considerable impact on water quality. The values of Chl-a and BOD were higher during the dry period, while all other parameters tended to show higher concentration during the wet period. According to the results, dilution was the primary factor influencing BOD and chlorophyll-a concentrations, whereas surface runoff played a predominant role in shaping the dynamics of the other water quality parameters.TN was the most responsive parameter to seasonal variations, with higher values in the wet season, possibly due to nutrient transport during rainfall. The degradation of water quality was strongly associated with urban and agricultural land uses, which contribute both point and diffuse sources of pollution. These areas often release excessive amounts of nutrients, organic matter, and sediments into water bodies, mainly through wastewater discharges and stormwater runoff.

Safe management of municipal solid waste incineration (MSWI) ash is essential to avoid detrimental effects of urbanization on the environment and human health. MSWI ash can potentially be used for carbon fixation by mineral replacement. Leaching of MSWI ash was conducted at various pH (7, 9, and 11) conditions and in the presence of additional carbonate ions (0–500 mmol/L). The concentrations of heavy metals in the resulting leachates were negligibly small (< 0.1 mmol/L), even in the presence of added carbonate ions, due to the higher stabilities of their oxide, sulfate, and carbonate species. Ca and Mg, which were significantly leached, were efficiently immobilized at higher pH or by adding carbonate ions; however, an excess of carbonate ions stimulated the release of B and F, increasing their leachate concentrations by factors of 2 to 5. X-ray diffraction and X-ray photoelectron spectroscopy analyses found that B- or F-bearing Ca/Mg minerals in the ash, such as calcium fluorite and layered double hydroxides, were converted to Ca/Mg carbonates. Thermodynamic calculations with geochemical modeling confirmed the mechanism of trace element release. The solubility of B- or F-bearing minerals was determined to be the dominant factor in preventing the leaching of these elements. The leaching potential of Ca/Mg is an essential factor in the carbon fixation capacity of MSWI ash; however, addition of excess carbonate ions induces conversion of the carbonate minerals, resulting in the release B and/or F.

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Highlights

• Trace elements in MSW incineration ash leachate is mobilized by carbonate ions.

• Carbonate ions convert Ca/Mg minerals into Ca/Mg carbonates, releasing adsorbed B and F.

• Ca leaching potential is a factor for carbon fixation without releasing B and F.

The widespread use of aluminum-based coagulants in ecological restoration projects has raised increasing concerns regarding the potential ecological impacts of residual aluminum (Al) in aquatic ecosystems. Epiphytic biofilms on submerged plants play a vital role in regulating nutrient cycling and energy flow in aquatic environments. However, the effects of Al on the biological and abiotic components of epiphytic biofilms on submerged macrophyte leaves remain poorly understood. In this study, we investigated the Al content in epiphytic biofilms on Vallisneria natans and its relationships with nitrogen, phosphorus and bacterial composition in Hangzhou West Lake, China. This location was selected due to the potential for residual Al into the lake from the daily pretreatment of the Qiantang River water diversion project—a water quality improvement project. Our results showed that Al contents in epiphytic biofilms decreased with increasing distance from the inlet and were positively correlated with total phosphorus, Chlorophyll-a and ash-free dry mass (P < 0.05), but showed no significant correlation with total nitrogen. Al accumulation enhanced Chl-a levels in biofilms by increasing the inorganic phosphorus content. Furthermore, Al content was positively correlated with the abundance of Cyanobacteria and negatively correlated with the abundance of Proteobacteria. Al also showed a significant negative correlation with key denitrifying bacteria, such as Vogesella and Phreatobacter, suggesting that elevated Al levels might affect the nitrogen cycling function in epiphytic biofilms. These findings provide important reference data for for ecological risk assessment and inform management strategies for aquatic systems undergoing restoration or exposed to aluminum-based treatments.

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Abandoned agricultural lands carry a legacy of soils contaminated with heavy metals from previous land use practices. Phytoremediation using fast-growing trees is widely used method for ecosystem restoration by accumulating heavy metals in aboveground biomass. In Northern Europe, where 1.8 to 2.6 million hectares of abandoned agricultural land can be afforested, the knowledge of fast-growing tree species' phytoremediation capacity is still poorly studied. This study examines the phytoremediation capacity after 20 years of afforestation of former agricultural lands with hybrid aspen plantations in hemiboreal Estonia, with a particular focus on the effects of different forest site type (Aegopodium, Dryopteris, Hepatica, and Oxalis) on heavy metal concentrations in topsoil and on bark and wood bioaccumulation factors. Soil, wood, and bark samples were collected from 24 sample plots to assess the allocation and accumulation of heavy metals in soil and biomass. The concentration of heavy metals in soil varied by site type, with waterlogged (Dryopteris) sites showing significantly higher levels of Cu, Fe, Ni, and Zn, whereas Cd and Mn were more concentrated in alkaline and dry (Hepatica) sites. The concentration of heavy metals in wood varied with tree size and age; smaller trees had significantly lower Cd, Cu, Fe, and Zn levels, while wood formed in the first decade of stand development showed higher concentrations of Cd, Cu, Mn, and Zn. Soil physical and chemical characteristics showed strong correlations with heavy metal bioaccumulation factors, particularly in bark. Soil pH negatively affected Mn bioaccumulation in all tree parts and Ni, Zn, and Cd in specific tissues, while soil P and available water content positively influenced metal uptake of trees. We found that the phytoremediation capacity of hybrid aspen plantations on former agricultural lands is controlled by soil properties and depends on tree size and age.

The widespread use of synthetic food dyes (FDs) across various industries, combined with the untreated discharge of FD-contaminated wastewater into the environment, presents significant challenges to both environmental and human health. Addressing this issue necessitates the effective removal of FDs from wastewater. Biochar (BC) technology emerges as a promising approach to environmental remediation due to its numerous advantages, including the availability of diverse raw materials, cost-effectiveness, and reusability. In this review, we categorize the removal of FDs using BC-based materials in detail according to their catalytic performance. We also introduce, for the first time, the potential of BC as an adsorbent, catalyst support, and composite catalyst for food dye degradation. It examines the removal of FDs from wastewater through adsorption and degradation processes using BC materials, while also analyzing the types, applications, and toxicity of FDs. Additionally, the research explores the application of BC in remediating various FDs, offering a roadmap for transformative solutions that foster cleaner and safer production practices within the food industry.

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In this study, the removal of a synthetic dye mixture containing anionic (Telon Blue AGLF), cationic (Astrazon Blue BG-200%), and nonionic (Dianix Blue S-BG) dyes from aqueous solutions was investigated using the adsorption method. As an alternative to commonly used commercial adsorbents, three low-cost, naturally abundant, and renewable materials magnolia cone (MC), beidellite (BD), and fly ash (FA) were selected. Unlike many previous studies in the literature, these adsorbents were used simultaneously to explore the potential advantages of combined adsorption. Batch adsorption experiments were conducted by varying the operational parameters, including pH (4–11), contact time (5–60 min), and the individual dosages of three different adsorbents (within the range of 0.01–0.04 g), while keeping the initial dye concentrations constant. A synthetic dye solution was prepared by mixing the three dyes in equal concentrations and volumes. The effects of the selected parameters on dye and total organic carbon (TOC) removal efficiencies were evaluated and optimized using Response Surface Methodology (RSM) based on Central Composite Design (CCD). To assess the structural and surface characteristics of the adsorbents before and after adsorption, Brunauer–Emmett–Teller (BET) surface area analysis and Scanning Electron Microscopy (SEM) were employed. BET analysis revealed surface areas of the adsorbents ranging from 18 to 158.5 m²/g. SEM images demonstrated that dye molecules were successfully adsorbed onto the surface and within the pores of the adsorbents. The findings indicate that the simultaneous use of natural and waste-derived materials can offer a sustainable, efficient, and cost-effective approach for the removal of mixed dyes from wastewater.

Limited information in China is available on how air pollution impacts daily hospitalizations for respiratory diseases before and under COVID-19 pandemic. Our aim is to investigate the potential effects of ambient air pollution and the pandemic on daily hospitalizations for respiratory diseases. Generalized additive model (GAM) are combined with Random Forest (RF) and Shapley Additive Interpretation (SHAP) method to analyze pollutant-hospitalization associations and rank pollutant importance based on a 9-year dataset from a tertiary grade A general hospital. Machine learning pinpointed PM_2.5, PM₁₀, and NO₂ as main drivers of increased hospitalizations, consistent with GAM risk estimates, while temperature as a covariate was second only to these three pollutants. During the whole periods, when PM_2.5 (8-day moving average, MA₀₇), PM₁₀ (MA₀₇), NO₂ (MA₀₇) and O₃-8 h (MA₀₅) rose by 10 μg/m³, daily hospitalizations increased by 2.19%, 1.35%, 2.84% and 0.94% respectively. It was 15.70% for every 1 mg/m³ rise in CO (MA₀₇). Specifically, PM_2.5, PM₁₀, NO₂ and CO at MA₀₂ effects strengthened during the pandemic, with hospitalization increases rising from 1.11%, 0.65%, 1.82%, and 12.41% before pre-pandemic to 1.91%, 0.69%, 3.9%, and 22.07%, respectively. The associations varied by individual characteristics, with males susceptible to PM₁₀ and females to PM_2.5. The effects of PM_2.5, PM₁₀, and NO₂ in the warm season were more pronounced than in the cold, although they tend to have lower concentrations. This study indicates that exposure to PM_2.5, PM₁₀ and NO₂ has a stronger impact on respiratory health than to other pollutants.

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Coastal regions worldwide face increasing threats from continuous sewage discharges. This review synthesizes current approaches for monitoring, mapping, and modelling of sewage contamination in coastal environments, including laboratory-based methods, in situ techniques, and remote sensing technologies. Existing studies mostly rely on biological tracers and nutrient indicators to detect sewage contamination. However, research remains limited in developing countries, where sewage discharges are more prevalent and poorly managed. The review also evaluates global legislative frameworks and management strategies, emphasizing their effectiveness, limitations, and adaptability. Emerging studies report the far-reaching impacts of sewage pollution on coastal ecosystems and human health. These impacts are now evident across global coastlines, regardless of the development status of the country and the effectiveness of local management. Key knowledge gaps persist, especially the lack of integrated monitoring frameworks and actionable management solutions. This review addresses these challenges and supports interdisciplinary research, coherent policy alignment, and active stakeholder involvement to control sewage pollution in the coastal environment.