Search Results (8,420)

Surface dust samples were collected from bus stops and parking lots in different functional areas of Binzhou City, Shandong Province, China. This study investigated the contamination characteristics, source apportionment, and potential ecological and health risks of potentially toxic elements (PTEs) in these dust samples. Eight target PTEs, including As, Zn, Pb, Cu, Cd, Cr, Ni, and Mn, were quantitatively analyzed. The results revealed distinct concentration differences in these elements between bus stop dust and parking lot dust. Several PTEs exceeded the corresponding local soil background values, predominantly Zn, Pb, Cu, Cd and Cr. Principal component analysis (PCA) indicated that Zn, Pb, Cu, Cr, Ni, and Mn in bus stop dust were mainly sourced from traffic emissions, whereas As and Cd primarily originated from atmospheric deposition. For parking lot dust, Zn, Pb, Cu, Cd, Cr, and Mn were predominantly attributed to traffic sources, while As and Ni were mainly derived from natural background sources. The geo-accumulation index (I_geo) demonstrated that As, Cr, Ni, and Mn had negligible environmental impact, Pb, Cu, and Cd induced slight pollution, and Zn resulted in moderate pollution. Except for Cd, the average individual potential ecological risk index ($E_r^i$) values for all elements were below 40, suggesting a low ecological risk. Cd posed a moderate ecological hazard, whereas the comprehensive ecological risk index ($E_r^i$) values of all analyzed elements were at an extremely low level. The hazard index (HI) values via different exposure pathways and for all PTEs in both bus stops and parking lots were lower than 1, indicating no significant non-carcinogenic health risk. The carcinogenic risk ranking of elements was Cr > Cd > Ni > As, and their carcinogenic risk values (CR) via inhalation exposure were below 1 × 10⁻⁶, indicating no carcinogenic risk. This study provides a scientific basis for the environmental quality control and risk management of surface dust in urban bus stops and parking lots. Full article

Changes in urban form strongly affect surface thermal conditions, yet long-term quantitative assessments of this relationship, particularly the role of ventilation resistance, remain limited. To address this gap, this study integrates XGBoost, SHapley Additive explanations (SHAP), and multi-scale geographically weighted regression (MGWR) to examine how six morphological, ecological, and human-activity factors influence land surface temperature (LST) in Kaifeng City. The results indicate three main findings. First, LST increased significantly from 1986 to 2024, while interannual variability declined, indicating a gradual reduction in regional thermal fluctuations. Second, NTL was consistently the dominant indicator across the five representative years, while BF and NTL together captured the effects of urban expansion and intensified human activity. Third, FAD coefficients were more spatially heterogeneous in urban fringe areas than in the urban core. In 2020, the dispersion of FAD coefficients in fringe areas was 2.74 times greater than that in the central area, indicating stronger spatial differentiation in ventilation-related morphological constraints during urban expansion. Although FAD made only a modest contribution to overall predictive accuracy, it provided supplementary diagnostic information not captured by conventional density indicators and showed nonlinear, directional, and spatially heterogeneous responses. Compared with previous studies that mainly examined short-term or single-dimensional relationships between urban morphology and LST, this study integrates building densification, ventilation-related morphological resistance, ecological conditions, and human activity intensity into a long-term LST-driver framework, providing evidence to support heat-risk management during urban regeneration and outward expansion. Full article

The urban heat island (UHI) effect represents a critical urban climate phenomenon arising from the combined pressures of rapid urbanization and climate warming. Although its association with carbon emissions has received increasing scholarly attention, the underlying behavior-mediated pathways and cross-regional spillover patterns remain insufficiently understood. Using multi-source geospatial data for the Yangtze River Delta urban agglomeration from 2014 to 2023, this study develops a multi-scale analytical framework integrating 1 km urban agglomeration exploratory analysis and 5 km spatial econometric modeling. Anthropogenic Energy Activity Intensity (AEAI) is constructed as a proxy for energy-related human activities, and a spatial Durbin model, combined with a spatial mediation approach, is employed to examine the spatial associations and statistically mediated pathways within the “heat-energy-carbon” nexus. The results indicate that: (1) carbon emissions exhibit significant positive spatial spillover effects, consistent with thermal diffusion processes and socioeconomic network interactions; (2) AEAI represents a substantial partial statistical mediation pathway in the association between UHI and carbon emissions, accounting for 44.63% of the total association. This suggests that the UHI–carbon emission linkage is partly embedded in spatial patterns of energy-intensive human activities rather than reflecting a purely direct thermal effect. These findings suggest that regional climate governance may need to move beyond single-city interventions and purely physical cooling strategies toward integrated approaches that combine cross-regional coordination with behavioral regulation. Promoting passive cooling-oriented urban planning and demand-side energy transitions may help reduce carbon lock-in risks and support the development of climate-resilient urban agglomerations. Full article

Long-standing studies of historical cultural spaces have primarily focused on the preservation of heritage objects and landscapes, while insufficient attention has been paid to the structural relationships, land-use transformations, and cultural–ecological processes that sustain their long-term continuity. Taking the World Heritage site of Lijiang as a case, this study develops a three-dimensional structural decoding framework composed of spatial base, spatial network, and spatial entity, together with an analytical pathway of “Identification–Interpretation–Evaluation–Synthesis–Practice.” By integrating qualitative and quantitative approaches with multi-source data, the study establishes an evidence chain linking historical processes and contemporary conditions to examine the formation mechanisms, continuity, and contemporary deviations of Lijiang’s historical cultural space. The results show that terrain–habitat adaptability, water system coupling, and environmental risk avoidance shaped environmental adaptation; historical corridors, landscape perception, and core node associations organized spatial networks; and functional diversity, cultural capital agglomeration, and spatial-scale compatibility supported entity-based spatial practices. Although tourism development, urban expansion, and land-use transformation have not completely dismantled these historical relationships, they have caused localized deviations in ecological boundaries, path continuity, visual connections, functional vitality, and spatial scale. This study argues that the governance of historical cultural spaces should shift from preserving isolated heritage objects to sustaining cultural–ecological relationships that support memory, identity, spatial practice, and adaptive land governance. Full article

While Japan’s population is declining overall, some areas remain densely populated within designated hazard zones. Understanding how these spatial patterns vary across urban contexts is important for sustainable and resilient urban development. This study presents a nationwide analysis of hazard-specific estimated population exposure at postcode-level population core cells across walkability-based urban spatial characteristics in Japan. We integrated designated hazard-zone layers from the Geospatial Information Authority of Japan (GSI) with 250 m census population grids and linked the resulting dataset to the Japan Postcode-level Walkability Index using these core cells as a common spatial unit. This analysis used postcode-level population core cells and was not designed to estimate total hazard-zone-based exposure within entire postcode areas. The four hazard-zone layers were analyzed separately to characterize hazard-specific patterns, not to assess simultaneous or compound hazard events, cumulative exposure, or compound risk. Population core cells in higher-JPWI strata generally overlapped more frequently with flood, storm surge, and tsunami inundation zones, whereas lower-JPWI population core cells overlapped more frequently with designated landslide warning zones. Where hazard-zone overlap was identified, estimated exposed populations tended to be larger in higher-JPWI core cells. The pattern should be interpreted descriptively because the estimate is partly influenced by cell population and JPWI includes a population-density component. Overall, the results show hazard-specific differences in how walkability-based urban spatial characteristics coincide with hazard-zone-based estimated population exposure, providing a transparent and nationally consistent baseline for characterizing designated hazard-zone overlap and estimated exposed population at population core cells in Japan. Full article

Pesticide contamination in urban runoff, stormwater, and peri-urban drainage networks is an increasing concern because of the persistence, mobility, and ecological toxicity of many pesticide residues and their transformation products. Nature-based solutions (NBSs), including constructed wetlands, bioretention systems, biofilters, and permeable reactive bio-barriers, provide low-energy and ecologically compatible platforms for urban water treatment; however, their performance is often constrained by limited sorption capacity, substrate saturation, variable hydraulic loading, and incomplete degradation of persistent pesticides. Biochar offers a multifunctional amendment for strengthening these systems because its tunable porosity, surface functionality, mineral composition, redox activity, and microbial habitat-forming capacity can support pesticide adsorption, catalytic transformation, and biodegradation. This review critically evaluates biochar-integrated NBSs for pesticide-contaminated urban water systems by linking biochar production and modification strategies with pesticide removal mechanisms, biochar–microbe interactions, engineered treatment configurations, and field-scale applicability. A comparative synthesis is provided across material-level mechanisms, system-level performance, machine learning-assisted prediction, techno-economic feasibility, life-cycle impacts, and environmental risk considerations. By integrating material properties, removal mechanisms, NBS configurations, predictive modeling, sustainability assessment, and risk considerations, this review provides a broader comparative basis than previous studies focused mainly on individual aspects of biochar-based pesticide remediation. Future priorities include standardized biochar production, long-term field validation, spent-biochar management, ecotoxicological assessment, and data-driven optimization of biochar-assisted NBSs. Full article

Urban ecological resilience (UER) has become a central concern in rapidly urbanizing regions where development pressures increasingly interact with ecological constraints. Focusing on the Guanzhong Plain Urban Agglomeration (GPUA), a semi-arid urban agglomeration in western China, this study examines the non-static and locally heterogeneous drivers of UER across 11 prefecture-level cities from 2000 to 2023. UER is measured through resistance, adaptability, and recovery. An extended STIRPAT model, Elastic Net with stability selection, two-way fixed-effects period interactions, and Geographically and Temporally Weighted Regression (GTWR) are integrated to identify robust drivers, test post-2011 shifts, and estimate city-year local associations. Residual Moran’s I diagnostics and Spatial Lag GTWR (SLM-GTWR) are used as supplementary checks. The results show that UER remains relatively stable at the aggregate regional level but becomes increasingly divergent across cities. Ten robust drivers are retained, with fiscal investment intensity, human capital, medical and health level, and total energy consumption emerging as key variables. Period heterogeneity results indicate that fiscal investment becomes more favorably associated with UER after 2011, while the marginal association of energy consumption weakens. GTWR reveals clear local heterogeneity: human capital shows the most stable positive association, medical and health level remains generally negative, fiscal investment is positive but context-dependent, and energy consumption is predominantly negative but locally differentiated. Supplementary spatial diagnostics suggest that the GTWR specification captures the main spatiotemporal structure of UER, while spatial-lag checks broadly support the robustness of the local coefficient patterns, although estimates of spatial interaction remain sensitive to how inter-city linkages are defined. These findings indicate that UER drivers are dynamic rather than fixed, with resilience formation shaped mainly by governance-regime shifts and localized heterogeneity. The study contributes a sequential screening–heterogeneity framework for identifying non-static resilience drivers and suggests that resilience governance should combine stage-sensitive policy adjustment, place-based intervention, and regional coordination where ecological functions and environmental risks cross administrative boundaries. Full article

Effective identification of corporate default risk is crucial for maintaining financial stability and safeguarding investors’ interests. Existing models remain limited in addressing class imbalance and the dynamic evolution of default-related features over time. To overcome these challenges, we propose an adaptive spherical neighborhood resampling and class-specific reliability evidential reasoning model (ASNR-crER). By combining feature-weighted minority sample reconstruction with reliability-guided recursive evidence fusion, the proposed model aims to improve the prediction accuracy of both default and non-default firms under class imbalance. This study uses Chinese listed small enterprises from 2000 to 2023 as the research sample, comprising 10,449 firm-year observations from 2182 firms. By matching default status in year t with firm indicators from t-0 to t-5, six rolling prediction windows are constructed. The empirical results show that: (1) Compared with mainstream benchmark methods, ASNR-crER achieves the best overall performance in terms of accuracy, AUC, and F1 across all prediction windows, indicating that it can more reliably identify high-risk default firms while maintaining strong recognition of non-default firms. (2) SHAP analysis indicates that financial, non-financial, and macroeconomic indicators exert time-varying effects on corporate default risk. Financial indicators, including “Retained earnings/total assets”, “Other receivables/current assets”, and “Annualized return on assets”, reflect internal capital accumulation and profitability, serving as key predictors of default risk. Non-financial indicators, such as “Top 10 Tradable Shares H-index” and “Top 10 shareholders H-index”, can provide supplementary signals for medium-term risk identification. Macroeconomic indicators, including “M2 YoY growth rate”, “Urban HH per capita income”, and “Benchmark short-term loan rate”, show stronger explanatory power in longer prediction windows. Therefore, this study provides an effective early-warning tool for financial institutions and relevant stakeholders to identify high-risk firms, and enriches empirical evidence on the time-varying drivers of corporate default risk. Full article

Rapid electric-vehicle adoption is reshaping urban energy and mobility systems, especially in multi-unit dwellings (MUDs), where concentrated charging in shared parking areas simultaneously stresses distribution transformers and amplifies the consequences of charger faults, battery thermal events, smoke spread, and emergency-access constraints. The central argument of this paper is that grid stress, resident-facing service quality, lifecycle cost, and fire-risk exposure in enclosed residential parking should be governed jointly rather than as four separate problems. To make that argument concrete, we develop an integrated framework that couples stochastic EV adoption, residential charging-behavior simulation, XGBoost demand forecasting, and linear-programming-based optimization for coordinated control, and we evaluate it through 1000 Monte Carlo trials on representative Turkish MUDs. Unmanaged charging triggers transformer overload at about 30% EV penetration, whereas coordinated control reduces peak demand by 44.7% (405 kW to 224 kW) and raises load factor from 0.40 to 0.68. Strict capacity protection exposes a sharp service–quality trade-off, with only 8.9% of users reaching 80% state of charge (SOC) by departure. Smart charging lowers upfront cost by about 55% ($200 vs. $439 per dwelling unit) and yields roughly $306 net present value per unit over ten years. Building on these results, we propose a five-pillar fire-risk-aware governance architecture—coordinated control, interoperability standards, time-of-use pricing, building–utility coordination, and monitoring—that turns coordinated charging into a preventive governance layer for reducing hazardous congestion in enclosed residential charging environments. Full article

This study examines the development of urban air mobility, which requires the creation of vertiports capable of ensuring the safe operation of electric vertical takeoff and landing (eVTOL) systems. Key operational constraints include unstable power supply, external climatic conditions, and reliance on battery systems. This study aims to develop a risk-based model for vertiport planning those accounts for the stochastic nature of eVTOL operational safety. A continuous-time Markov model incorporating nominal operational characteristics, system constraints, and transitions into emergency and catastrophic flight modes is proposed. State transitions within the model are primarily driven by climatic indicators, power supply reliability, battery parameters, maintenance quality, and diagnostic coverage. To interpret the low probabilities of transitioning to a catastrophic mode, this study introduces a safety index (integrated safety index), which facilitates the comparison of various operational scenarios and regulatory maturity levels. The practical importance of the research lies in applying the proposed model to precisely select vertiport locations; assess energy infrastructure requirements; and organize onboard monitoring, robotic preflight inspection systems, and decision support systems. The results demonstrate that eVTOL operational safety is assessed not only through spatial and infrastructure metrics but also through an integrated indicator encompassing power supply, climate, battery degradation, diagnostics, and hardware–software reliability of the entire vertiport system. Full article

Identifying where nature-based solutions should be prioritized has become a critical task for climate-adaptive urban stormwater management under the combined pressures of climate change and urban expansion. Taking the central urban area of Beijing as a case study, this study develops a dynamic prediction framework that incorporates the Source–Flow–Sink (SFS) process of urban waterlogging. The framework integrates a future land use simulation model (FLUS), the Soil Conservation Service (SCS) hydrological model, and the Maximum Entropy (MaxEnt) model and incorporates both climate change (RCP8.5) and urban expansion to simulate the spatial configuration of waterlogging risk in 2031. High-risk areas were then overlaid with land-cover data and open-space distribution to identify potential NbS opportunity spaces, which were further examined through field investigation. The results show that future waterlogging risk in Beijing exhibits a clear corridor-oriented pattern closely associated with transportation infrastructure. Transportation-related variables account for more than 80% of total model contribution, suggesting a strong statistical association between future waterlogging occurrence and transportation-related spatial features. Field investigation further reveals that many roadside green spaces are elevated above adjacent roads, limiting their ability to receive and retain runoff. Thus, the key adaptation challenge lies not simply in the amount of green space, but in the weak hydrological connection between runoff pathways and adjacent open spaces. While Beijing’s priority areas are mainly corridor-based, other cities may be shaped by different processes and spaces. More broadly, this study demonstrates how hydrological risk simulation can be translated into spatially explicit planning priorities and more locally grounded adaptation decisions. Full article

Land-use change poses a growing threat to ecological security, yet existing regional assessments often rely on a single ecological indicator and lack direct linkage to territorial spatial planning. This study develops an integrated ESV–ERI framework coupled with quadrant zoning to provide spatially explicit, planning-compatible guidance for ecological protection in tropical island regions. Taking Hainan, China, as a case study, this research draws on land-use data from 1994 to 2024, applying ESV and ERI assessments coupled with Z-score standardization to examine their spatiotemporal evolution characteristics. The results indicate the following: (1) forest land persistently dominated land use (>63%), while construction land expanded by 197.68% and forest land and grassland decreased by 9.36% and 93.78%, respectively. (2) ESV showed a downward trend, decreasing by 14.683 billion yuan, with forest land accounting for over 83% of total ESV. Spatially, ESV exhibited a “high inland, low coast” pattern, with high-value zones across inland water bodies and central nature reserves and low-value zones in coastal urban agglomerations. (3) ERI increased from 0.0371 to 0.0539, with low-risk zones in the middle mountains and high-risk zones around the island. (4) Based on the dual dimensions of ESV and ERI, the entire island was delineated into four ecological zones. These findings provide scientific decision support for territorial spatial planning and differentiated ecological protection in tropical island regions. Full article

Bats (Chiroptera) account for approximately 25% of all known mammalian species and provide essential ecological services, including insect regulation, pollination, and seed dispersal. Despite their importance, they face significant conservation threats and persistently negative social perceptions. Owing to their innate immunity and tolerance, bats constitute a particularly efficient natural reservoir for a wide variety of potentially zoonotic viruses. Over the past two decades, bat-associated viruses have been central to multiple outbreaks of emerging infectious diseases. From severe acute respiratory syndromes to filoviral hemorrhagic fevers, bats have consistently acted as key reservoirs in pathogen emergence. This has further damaged the public perception of bats as dangerous animals and vectors of serious diseases, in some cases leading to increased persecution of their populations. However, spillover events should not be attributed to bats, but rather to human-driven environmental changes—including deforestation, land-use transformation, agricultural intensification, urban expansion, biodiversity loss, wildlife trade and research biosecurity—that amplify contact among humans, livestock, and wildlife or their potential zoonotic pathogens. Safeguarding bat populations, minimizing direct interactions with wildlife, and preserving intact ecosystems are critical not only for bat conservation but also for reducing zoonotic spillover risk. Furthermore, it is essential to strengthen social communication regarding the importance of bats, in order to counteract their negative reputation and promote greater public understanding of their ecological value. This article reviews health, sociological, and conservation dimensions of the issue, situating them within a broader context to provide an integrated, multidisciplinary understanding. Potential solutions and priority directions for future research are also discussed. Full article

Reprocessing historical lead–zinc (Pb–Zn) slag offers a circular-economy pathway for secondary metal recovery, yet it can remobilize legacy contaminants where containment is inadequate, transferring risk to the surrounding land. Sustainable management of such sites requires frameworks that link contamination assessment to actionable remediation. We integrated ICP-OES geochemistry, native-plant biomonitoring, and US EPA RAGS-based risk modeling at an active Pb–Zn slag reprocessing site in Shymkent, Southern Kazakhstan. Twenty-four soil samples along four cardinal transects, two reference samples, and four composite plant samples (Centaurea pseudosquarrosa + Plantago lanceolata) were analyzed for ten metals by ICP-OES. UCC-referenced indices classified six metals as geoaccumulation Class 6 at most points (enrichment factors up to 90,871, confirming an exclusively anthropogenic origin). Peak concentrations reached 9350 mg·kg⁻¹ Pb, 290 mg·kg⁻¹ Cd, and 10,900 mg·kg⁻¹ As—exceeding Kazakhstan MPC by 72×, 290×, and 5450×. Worst-case carcinogenic risk reached 4.3 × 10⁻³ (43× above the US EPA threshold), driven almost entirely by arsenic (93%); ecosystem risk (RCR_total = 223) was dominated by cadmium (43%), arsenic (27%), and mercury (16%)—a disconnect between mass-based and toxicity-based prioritization. On this basis we propose a three-tier remediation framework (engineered containment, phytostabilization, monitored attenuation) that couples resource recovery with contamination control, is transferable to analogous Pb–Zn legacy sites, and supports sustainable land use, urban resilience, and responsible secondary-resource use. Full article

Resource-based cities face complex land-use pressures. Examining the evolution of production–living–ecological spaces (PLESs) and the spatial conflicts associated with this evolution provides an important basis for reducing land-use tensions and promoting more coordinated and sustainable spatial development. Drawing on land-use records spanning 2000–2020, this study integrates a transfer-matrix approach, a PLES conflict assessment model, and spatial autocorrelation analysis to examine the spatiotemporal evolution of PLESs and their conflict patterns in Shenmu City, China. The results show that (1) industrial production land expanded more rapidly than any other land category, mainly through the conversion of agricultural production land. Agricultural production land continued to decrease as it was converted into both industrial production land and ecological land. Grassland served as an important transitional space between production and ecological spaces, with its evolution shifting from rapid expansion in the early period to relative stability in the later period. (2) In terms of spatial conflicts, moderate conflict remained the dominant category and generally increased over time. By contrast, strong and relatively strong conflicts decreased, while weak and relatively weak conflicts gradually increased. Spatially, conflict patterns shifted from highly concentrated areas in the southeastern resource-extraction zone to a more dispersed and balanced regional distribution. (3) Global Moran’s I decreased from 0.62 to 0.49, indicating a weakening of overall spatial clustering. High–High clusters contracted into fragmented patches, whereas Low–Low clusters continued to expand in the northwestern ecological zone, reflecting the gradual improvement of local environmental conditions. Overall, although spatial conflict intensity has decreased and strong conflicts have been substantially reduced, conflicts have shifted mainly toward moderate levels rather than being fully resolved. As the dominant and still expanding category, moderate conflict represents a potential risk that requires continuous monitoring and adaptive intervention. By focusing on a county-level resource-based city, this study provides a fine-grained empirical case. It identifies an evolutionary pattern characterized by the reduction in severe spatial conflicts and the accumulation of moderate conflicts, which differs from the patterns commonly observed in urbanization-driven cities. The findings suggest that spatial conflicts in resource-based cities are highly responsive to targeted ecological governance policies. Future sustainable spatial development should be promoted through differentiated zonal governance, ecological restoration, and the green transformation of the industrial structure. Full article