Search Results (336)

In this study, we present a machine-learning approach—a land use random forest (LURF) model—to produce daily PM₁₀ concentration maps at a 1 km resolution across the Campania region for the year 2022. The model combines daily measurements from 13 ARPA Campania monitoring stations with a wide set of spatial and atmospheric information. The predictors include population, land cover, road network, ERA5 meteorological data, satellite aerosol observations from MODIS, output from the CHIMERE chemistry transport model, and a flag identifying days affected by Saharan dust transport. The model is trained and validated using a station-based cross-validation scheme that accounts for spatial correlation between sites. Under this scheme, the LURF reproduces observed concentrations with substantially smaller errors than the raw CHIMERE output (RMSE of 11.0 vs. 23.6 $\mathsf{\mu }$g m⁻³). CHIMERE concentrations and ERA5 meteorology emerge as the most informative predictors, while the dust flag specifically improves the representation of episodic high-PM₁₀ events. The resulting 1-km maps reveal clear urban–rural contrasts. They identify pollution hotspots in the Naples metropolitan area and along major motorways that are not visible in coarser model outputs. Probabilistic exceedance maps further show that meeting the future 2030 EU limit value of 20 $\mathsf{\mu }$g m⁻³ will be challenging across much of the metropolitan area. Overall, the proposed framework provides a low-cost, practical tool for high-resolution PM₁₀ exposure assessment, supporting epidemiological studies, environmental justice analyses, and air quality management in regions with complex terrain and limited monitoring coverage. Full article

The construction of green mines is a core strategy for promoting ecological civilization in China’s mining sector, yet its long-term ecological effects require quantitative assessment. Using a cement-grade limestone mine operated by Linyi Zhonglian Cement Co., Ltd. in Shandong Province as an illustrative case, we employed Landsat 8 OLI/TIRS imagery acquired in 2015, 2020, and 2025 to develop a five-indicator framework for assessing ecological environment quality. The selected indicators comprised greenness (NDVI), wetness, dryness (NDBSI), land surface temperature (LST), and dust concentration (MECDI). These five indicators were subsequently integrated via principal component analysis to generate the Mine Ecological Quality Index (Mine-EQI). Using this index, we applied the Theil–Sen median slope estimator alongside zonal statistics to examine ecological change trajectories across the full study area and three functional zones—the industrial square, haul roads, and active mining area—over the 2015–2025 period. The ecological outcomes attributable to the green mine policy were then quantified. The results show that (1) the mean Mine-EQI of the study area decreased from 0.3713 in 2015 to 0.3460 in 2025, exhibiting a slight overall decline. However, the rate of decline decreased from −6.1% during 2015–2020 to −0.7% during 2020–2025, yielding a Temporal Change Intensity index (TCI) of +88.5%, indicating that the ecological degradation trend has been effectively curbed. (2) Significant spatial heterogeneity was observed. The industrial square showed substantial improvement (Theil–Sen slope = +0.0726), while the haul roads (slope = −0.0705) and mining area (slope = −0.0408) continued to exhibit degradation trends. The improved areas (9.7% of the study area) were spatially coincident with green mine engineering projects. (3) The dust indicator (MECDI) decreased by 24.7% during 2020–2025, and the vegetation index (NDVI) increased by 19.5% over the decade, representing the dominant contributors to ecological improvement. This study reveals that China’s green mine policy has yielded remarkable ecological improvements in relatively stable functional zones such as industrial squares. In contrast, ecological restoration within persistently disturbed areas, including haul roads and mining pits, demands long-term sustained investment and governance. By integrating remote sensing techniques with policy analysis, this research establishes a replicable framework for evaluating progress toward sustainable mining practices. The findings directly support the monitoring of SDG 12 (Responsible Consumption and Production) and SDG 15 (Life on Land), providing a quantitative pathway to balance mineral resource extraction with ecological protection—a core sustainability challenge for resource-dependent regions. Full article

Urban trees are increasingly exposed to persistent anthropogenic drivers that extend beyond climatic forcing and fundamentally alter the conditions of secondary growth. While climatic controls of cambial phenology and xylogenesis are well established, the mechanisms by which non-climatic drivers regulate cambial activity and wood formation remain fragmented and are often inferred only indirectly. Here, we develop a cambium-centred framework to synthesise current evidence on how anthropogenic drivers shape wood formation in urban and peri-urban trees. To our knowledge, this is among the first syntheses explicitly linking anthropogenic drivers to distinct stages of xylogenesis. Anthropogenic drivers are typically chronic, spatially heterogeneous, and temporally decoupled from seasonal climatic rhythms, and may alter cambial kinetics and generate anatomical signatures not captured by ring width alone. We evaluate major driver domains, including root-zone constraints, altered hydrology, urban microclimate, pollution, salinity, and mechanical disturbance, while also considering emerging drivers such as artificial light at night and microplastics. Evidence is stratified into three levels: direct observations, indirect physiological evidence, and mechanistic plausibility. Across driver classes, three recurrent anatomical patterns emerge: reduced conduit size under hydraulic or osmotic stress; anomalies in wall deposition under carbon limitation or oxidative stress; and pronounced circumferential heterogeneity under spatially localised forcing. Integrative approaches combining xylogenesis monitoring, quantitative wood anatomy, dendrometer observations and spatially explicit sampling are essential to disentangle anthropogenic from climatic effects and improve assessment of tree resilience. Full article

With the rapid evolution of urbanization and artificial intelligence technology in China, small, intelligent road sweepers have emerged as a highly promising technical solution to address urban cleaning challenges. The development and breakthrough of high-performance dust collection trays (DCT) stand as the core prerequisite for the large-scale practical application of such sweepers. Although blowing–suction integration technology theoretically offers substantial potential for improving dust removal efficiency, it has not received adequate attention in the sweeper field, particularly in the research on its application in unmanned, small-sized models. In this study, a fresh concept of an efficient DCT was proposed, and its numerical method was verified by experiment. Then, the design work for this efficient DCT was efficiently carried out by combining computational fluid dynamics (CFD) numerical simulation with response surface methodology (RSM). Finally, the influence mechanisms of three key operational parameters of nozzle airflow velocity, suction negative pressure, and vehicle travel speed on the dust removal effect were numerically investigated. The results indicated that the parameter combination of DCT with an 18° blowing angle, 20° shoulder angle, and 0.2 diameter-to-length ratio was recommended, and its dust removal efficiency could reach a peak level of 98.7% when the nozzle blowing velocity, negative pressure at suction port, and travel speed were respectively 14 m/s, −1800 Pa, and 1.4 m/s. This research provides important theoretical support and a feasible technical pathway for the design of high-performance DCTs. Full article

Zora Neale Hurston describes herself as “a crow in a pigeon’s nest” in her autobiography, Dust Tracks on a Road. For Hurston, the metaphor illustrates her singular perspective as an atypical presence in what she considered a stereotypical environment—or, put differently, the difference her presence made in a dominant space. Katherine McKittrick describes metaphors as “observational scaffolding.” Observational scaffolding functions as both a signal and a map, highlighting sites of struggle and liberation along the continuum of life’s experiences. Therefore, this article engages with discourses on decolonization and Black feminist epistemologies, acknowledges the differences between Hurston’s and today’s anthropology, and challenges other disciplines and fields to reconsider how values such as democracy and justice might influence engagement with Black knowledge production, specifically from Black women. Full article

Collisions between over-height vehicles and low-clearance bridges cause infrastructure damage and pose safety risks. Existing detection systems rely primarily on optical sensors, which suffer from performance degradation in adverse weather conditions. This paper presents an alternative approach based on a 94 GHz millimeter-wave radar that achieves velocity-independent height measurement. The proposed technique exploits the ratio of Doppler shifts from two scattering centers on a vehicle, specifically the roof and the wheel–road interface. This ratio depends only on the measurement geometry, as the unknown vehicle velocity cancels algebraically, enabling direct height computation without speed measurement. The paper provides a closed-form height estimation model, analyzes the trade-off between frequency resolution and geometric constancy during integration, and presents experimental validation using a scaled laboratory testbed. An optical tracking system is used solely for ground-truth validation in the laboratory and is not required for operational deployment. Results across six test cases with heights ranging from 20 cm to 46 cm demonstrate an average absolute error of 0.60 cm and relative errors below 3.3 percent. A scaling analysis for representative full-scale geometries indicates that at highway speeds of 80 km/h, integration times in the millisecond range (approximately 3–18 ms for representative 20–50 m measurement standoff) are feasible; warning distance can be extended independently by upstream radar placement. The expected advantage in fog, rain, and dust is based on established W-band propagation characteristics; dedicated adverse-weather and full field validation (including multipath, clutter, and multi-vehicle scenarios) remain future work. Full article

Open-air asphalt milling generates hazardous respirable crystalline silica (RCS), posing severe risks to operators of legacy machines lacking enclosed cabs. This study evaluates a novel, standalone retrofit water spray system designed to intercept fugitive dust. Field validation across 11 road maintenance sites involved particle characterization and paired system-off/on exposure monitoring. Results indicated a Mass Median Aerodynamic Diameter (MMAD) of 6.12 µm, confirming the efficacy of fine-atomizing nozzles (0.3 mm) for capturing respirable fractions. The system achieved RCS suppression efficiencies ranging from 60% to over 85% under low-to-moderate wind conditions (<2.5 m/s). A comparative analysis revealed no significant performance gain from larger 0.5 mm nozzles, supporting the use of smaller orifices for optimal water conservation. However, suppression efficacy degraded significantly when crosswinds exceeded 2.5 m/s, indicating a potential operational boundary. This retrofit solution provides a scientifically validated, cost-effective engineering control for reducing occupational silica exposure in aging road maintenance fleets. Full article

Urban storm drain sediments (SDSs) accumulate heavy metals from building façades and road surfaces, yet the biogeochemical controls governing metal mobility remain poorly understood. This study investigated biotic and abiotic controls on metal mobility along the urban dust transport chain (Xiamen-Quanzhou-Zhangzhou, China), using four sample types—façade dust (FD), road-deposited sediment (RDS), SDS, and runoff suspended solids (RSS)—from nine sites across three functional zones. Metal concentrations (Pb, Cu, Zn, Cr, Cd), phosphorus fractions, and microbial functional genes were quantified to test the hypothesis that viral abundance indicators, rather than pH, are more strongly associated with metal mobility in near-neutral urban sediments. Results showed that SDS served as metal accumulation hotspots with enrichment factors of 2.0–2.3× relative to FD, while total phosphorus declined by 34% along the transport chain. Contrary to conventional expectations, pH exhibited weak correlation with Pb mobility (r = −0.21; 95% CI: −0.62 to 0.27), whereas the T4-type bacteriophage gene g23 showed strong positive correlation (r = 0.85, p < 0.01; 95% CI: 0.52–0.96). Partial least squares path modeling revealed that viral abundance (g23 gene copies) showed the strongest statistical association with metal mobility among biotic variables (β = +0.48, p < 0.001), mediated through phosphorus-supported microbial activity. The model explained 76% of variance in metal mobility, with phosphorus cycling positively influencing viral abundance (β = +0.28). These findings challenge the pH-centric paradigm of metal geochemistry and reveal a novel phosphorus-virus-metal coupling mechanism in urban environments. The textile industrial site QZ-2 exceeded chromium screening values by 45%, demonstrating the framework’s utility for pollution hotspot identification. Full article

Urban road dust is an important way for people to contact potentially toxic elements (PTEs). However, the correlation between the bioaccessibility of PTEs in road dust and the contribution rate of pollution sources has not yet reached a consensus. Road dust was divided into three particle sizes (<63, 63–125, and 125–250 μm). Then, the Mantel test was used to analyze the correlation between the contributions of the four pollution sources (composite sources, traffic sources, industrial sources, and fuel combustion) and the bioaccessibility of PTEs. Finally, by incorporating bioaccessibility into the health risk assessment system, Ni was identified as the priority lifetime carcinogenic risk element and fossil fuel combustion as the priority pollution source. The remediation target obtained by the probabilistic risk assessment of bioaccessibility guidance is 3.91 times the target value based on the total content and reduces carbon emissions by 22.6%. Overall, this study not only enhances the precision of identifying pollution sources and pollutants in complex urban environments by integrating PMF with the bioaccessibility of PTEs but also highlights the potential value of bioaccessibility in urban environmental management for carbon emission reduction. This facilitates the implementation of precise risk assessments and low-carbon sustainable development. Full article

Rain, snow, fog, and dust can degrade road-scene images, blur fine details, and consequently reduce the reliability of perception systems for autonomous driving. To address this problem, this paper proposes PF-ConvNeXt, an adverse weather recognition model built upon the ConvNeXt architecture. First, a lightweight pyramid split attention (PSA) module is introduced to enable multi-scale feature fusion, so that both global degradation patterns and local texture details can be captured simultaneously. Second, a feature enhancement channel and spatial attention module (FECS) is designed. It adaptively recalibrates features along the channel and spatial paths, thereby suppressing interference from complex backgrounds and noise. Third, during training, Focal Loss is adopted to strengthen learning for hard samples and minority weather categories, alleviating recognition bias caused by class imbalance. Experiments are conducted on a dataset of 5000 images constructed by integrating RTTS, DAWN, and a self-collected rainy-weather dataset. The results show that PF-ConvNeXt achieves 90.16% accuracy, 95.24% mean average precision, and a 92.18% F1-score. It outperforms the ConvNeXt baseline by 4.74%, 5.46%, and 5.95%, respectively, and surpasses multiple mainstream classification models. This study provides an effective recognition framework for robust environmental perception under challenging weather conditions and demonstrates promising potential for practical deployment. Full article

Particulate Matter (PM) is a type of air pollution that poses risks to human health, the environment, and property. Among the various PM types, PM₁₀ is particularly significant, as it acts as a vector for numerous hazardous trace elements that can negatively impact human health and the ecosystem. Identifying potential sources of PM₁₀ and quantifying their impact on ambient concentrations is crucial for developing efficient control strategies to meet threshold values. Receptor modeling, which identifies sources using chemical species information derived from PM samples, has been widely used for source apportionment. In this study, PM₁₀ samples were collected over three periods (April, May, and June 2021), each lasting 16 days, using semi-automatic dust sampling systems at two sites in Biga, Canakkale, Turkiye. The relative contributions of different source types were quantified using EPA PMF (Positive Matrix Factorization) based on 35 elements comprising PM₁₀. As a result of the analysis, five source types were identified: crustal elements/limestone/calcite quarry (64.9%), coal-fired power plants (11.2%), metal industry (9%), sea salt and ship emissions (8.5%), and road traffic emissions and road dust (6.3%). The distribution of source contributions aligned with the locations of identified sources in the region. Full article

Brake dust (BD) generated by vehicle braking systems, including those of cars and trains, contains various Potentially Toxic Elements (PTEs) that may pose risks to human health and the environment, particularly in soils where it accumulates. This study aims to evaluate differences in the chemical composition of BD emitted by road and railway transport, to analyze its deposition mechanisms in soil, and to estimate the associated carcinogenic (CR) and non-carcinogenic (HQ) risks from ingestion and dermal exposure. Two sites were selected: one adjacent to a busy roadway and the other near a railway line. At both locations, soil-sampling transects were established perpendicular to the emission sources at distances of 3, 6, 15, 25, and 45 m. Elemental concentration analyses were integrated with magnetic measurements, which are selective for magnetic iron oxide particles. The results confirm elevated concentrations of several metals at both sites. Both elemental and magnetic data reveal a clear deposition gradient, with the highest accumulation within 15 m of the source, followed by a gradual stabilization up to 45 m. However, the railway site exhibited significantly higher concentrations than the road site, highlighting the relevance of non-exhaust emissions (NEEs) from railway traffic, which remain poorly investigated. While HQ was non-significant, CR associated with Pb-, Ni-, and As-rich BD exceeded acceptable threshold values, particularly for ingestion exposure at the railway site. These results highlight the significance of NEEs from rail traffic in terms of soil contamination and risk assessment. Full article

The principal global sources of platinum-group elements (Os, Ir, Ru, Rh, Pt, Pd), collectively referred to as PGEs, are magmatic Ni-Cu sulfide deposits associated with large, layered intrusions, such as the Bushveld Complex. Recent exploration efforts have identified rock types with elevated PGE concentrations, although their potential remains uncertain. This comprehensive review synthesizes the current knowledge regarding potential sources from both natural magmatic and anthropogenic activities, as well as the environmental risks associated with the Pt, Pd, and Rh sub-group, or PPGEs. The order of Pd > Pt > Rh content in emitted particulates has been documented in dust and soil along roadsides, whereas in Fe-Ni laterite, Pt tends to accumulate residually at the top of profiles due to the higher mobility of Pd compared to Pt and Rh. The greater mobility and transfer of Pd are evidenced by higher bioaccumulation factors for Pd in plants and crops, with a higher Pd content observed in roots than in shoots. The effects of chronic occupational exposure to Pt compounds, such as allergic reactions affecting the skin and respiratory system of workers, are well-documented. Although no established permissible limits for Pt, Pd, and Rh in soil, water, or plants exist within major regulatory frameworks, the increasing applications of PPGEs and the use of Pd in catalytic converters (due to its lower cost) underscore the need for further studies on the recycling of spent catalytic converters, health impacts, ecotoxicological assessments, and the application of current technological advances to mitigate exhaust emissions. Full article

Following the implementation of the Shanghai Clean Air Act, this study investigates the evolution of air pollution in central Shanghai (Putuo District) by analyzing continuous monitoring data (2016–2020) and chemical speciation of particulate matter (2017–2018). The results confirm a transition toward a “low exceedance rate and low background concentration” regime. However, short-term exceedance episodes persist, generally occurring in winter and spring, with significantly amplified diurnal variations on exceedance days. Distinct patterns emerged between PM fractions: PM₁₀ exceedances were characterized by a single morning peak linked to traffic-induced coarse particles, while PM_2.5 exceedances showed synchronized diurnal peaks with NO₂, suggesting a stronger contribution from vehicle exhaust. Source apportionment revealed that mineral components (21.61%) and organic matter (OM, 21.02%) dominated in PM₁₀, implicating construction and road dust. In contrast, PM_2.5 was primarily composed of OM (26.73%) and secondary inorganic ions (dominated by nitrate), highlighting the greater importance of secondary formation. The findings underscore that sustained PM_2.5 mitigation requires targeted control of gasoline vehicle emissions and gaseous precursors. Full article

Civilisational progress contributes to an increase in the number of vehicles on the road, thereby intensifying air pollutant emissions and accelerating the degradation of the natural environment. Effective protection of urban areas against air pollution enhances safeguarding against numerous allergies and diseases resulting from unplanned and unintended absorption of harmful pollutants into the human body. Sustainable urban planning requires the collaboration of multiple scientific disciplines. In this context, measurement becomes crucial, as it reveals the spatial scale of the problem and identifies existing disparities. This study uses an integrated approach of standard measurement methods and statistical and geostatistical data analysis, identifying PM₁ fractions that are not included in EU air quality monitoring. The hypothesis explores how surface-based results correspond to point-based results from national air quality monitoring. The presented implications demonstrate similarities and differences between the studied measurement methods and the spatial distributions of PM₁₀, PM_2.5, and PM₁ dust. Full article