Search Results (2,007)

Studying the response of urban functions to residents’ spatiotemporal activity patterns is essential for understanding urban functions and guiding resource allocation. Unlike previous studies constrained by fixed intervals and static functional spaces, this study has developed an analytical framework to examine urban functional responses to residents’ activity patterns under dynamic spatiotemporal combinations. Tensor decomposition was employed to identify key temporal activity patterns of residents and dynamic urban functional patterns, while a Random Forest model was used to evaluate the contributions of five POI (Points of Interest) groups—Transportation, Organizations, Leisure, Habitation, and Basic Facilities—derived from a reclassification of 17 original POI categories, and the Elasticity Index (EI) quantifies functional responsiveness to activity changes. Results indicated that (1) four temporal patterns (sleeping, commuting, daytime, and leisure) and four spatial function types (the basic living area, the residential areas with mixed functions, residential areas with commercial functions and bustling business districts) characterized Beijing’s urban dynamics; (2) the five types of urban function varied with spatiotemporal context, with basic living POIs dominating daytime activities in residential zones and transportation POIs prevailing during commuting in mixed-use areas; (3) EI revealed significant spatial heterogeneity in adaptive capacities to activity transitions, which helped to accurately identify the key areas for improving urban functions. These findings provide new methodological insights and scientific evidence for resilient urban planning and resource optimization, supporting data-driven decision-making for spatial planning, infrastructure allocation, and emergency response management. Full article

China’s rapid urbanization, characterized by extensive land allocations, operates within a framework of binding quotas imposed by upper-level governments, while local governments exercise broad discretion over the zoning of newly transacted land parcels. In this context, investigating the evolving patterns of land supply structure during this period is therefore of critical importance. The central government’s 2018 articulation of the “Houses are for living in, not for speculation” (fangzhubuchao) sought to mitigate housing market speculation and curb potential asset bubbles, including through changes to residential land supply. Using a panel of 266 prefecture-level cities across China, this study employs a generalized difference-in-difference model to examine how housing market regulations affect the industrial sector through adjustments in land supply. To capture cross-city variations in local policy interventions, we construct a measure based on the land price wedge between residential (and commercial) and industrial land derived from a hedonic pricing model, which reflects underlying housing market conditions. The results indicate that a reduction in residential land supply caused by these policies results in a corresponding increase in industrial land supply, while the total land supply remains unchanged. These effects are more pronounced in cities with stringent policy regulations and relaxed urban land quotas. The short-term economic outcomes are inadequate. As of 2023, our analysis reveals no substantial increase in either the number of industrial enterprises or the industrial value added, notwithstanding the augmented industrial land supply. Consequently, these findings identify a secondary determinant of industrial location patterns and provide a scientific basis for designing efficient land-use regulations and sustainable urban development strategies. Full article

Land economic density (LED) is vital for optimizing industrial structure and promoting intensive resource utilization. However, most existing studies have focused on city or county scales, with limited attention to township-level patterns. To address this research gap, we take 86 townships in Anyang City as research units and develop a four-dimensional evaluation system for LED. The study aims to reveal the spatial patterns and driving mechanisms of township-level LED evolution. This study is based on township-level land use, statistical, and socioeconomic data from 2005 to 2023. Using ArcGIS 10.5 for spatial analysis, spatial autocorrelation, standard deviation ellipse, and geographically weighted regression methods were applied to explore the spatiotemporal evolution and driving mechanisms of LED in Anyang City. The results indicate that (1) high-LED areas form a ring around the central city with dual cores in western Linzhou county and southeastern Huaxian county, while low-LED areas are concentrated at the northwestern and northeastern margins; (2) global spatial autocorrelation is weak, with low–low clusters shrinking from contiguous patches to only three townships by 2023, while high–high clusters expand from isolated points to multi-centered diffusion; (3) the ellipse consistently shows a northwest–southeast orientation, with the rotation angle increasing from 128.24° to 130.35°, the flatness ratio rising from 0.432 to 0.445, and the centroid shifting northwest then southeast; (4) The geographically weighted regression (GWR) results highlight economic foundation, industrial upgrading, and government support as the dominant drivers. Based on these findings, we propose a “One Core–Four Poles, Three Axes–Five Zones” spatial optimization framework to promote coordinated urban–rural development. This study provides a practical and multidimensional evaluation approach at the township level, offering methodological support for regional territorial spatial planning and sustainable development. Full article

Seismic risk assessment in megacities requires a high-resolution spatial framework that can capture the intrinsic heterogeneity of local geology, building distribution, and population characteristics beyond conventional administrative boundaries. This study develops a hazard-independent seismic susceptibility framework for the Seoul Metropolitan Area, a megacity of approximately 9.5 million residents (as of 2024), where historical and instrumental earthquake records are limited. The proposed framework integrates nine standardized indicators across geotechnical, structural, and social domains within a vulnerability–exposure model, analyzed on a 250 m grid—approximately 300 times finer than district-level assessments. Domain-specific indices and the integrated Seismic Susceptibility Index (SSI) were derived using Analytic Hierarchy Process (AHP)-based weighting to quantify the relative importance of indicators. Results show a highly concentrated spatial pattern of susceptibility: only 2.2% of Seoul (229 grids, 14.3 km²) falls within the high-to-very-high categories, primarily in northern and southwestern residential zones characterized by soft soils, aging buildings, and vulnerable populations. The proposed framework supports targeted risk-reduction strategies by providing a practical basis for pre-disaster decision-making and efficient allocation of mitigation resources in data-scarce urban environments. Full article

Buildings crossing active faults often suffer severe damage due to fault dislocation during direct-type urban earthquakes. This study employs physical model tests to systematically investigate the dynamic response mechanisms of the integrated “surface rupture zone–overburden–foundation–superstructure” system subjected to bedrock dislocation. A testing apparatus capable of simulating reverse faults with adjustable dip angles (45° and 70°) was developed. Using both sand and clay as representative overburden materials, the experiments simulated the processes of surface rupture evolution, foundation deformation, and structural response under varying fault dislocation magnitudes. Results indicate that the fault rupture pattern is governed by the bedrock dislocation magnitude, soil type, and fault dip angle. The failure process can be categorized into three distinct stages: initial rupture, rupture propagation, and rupture penetration. The severity and progression of structural damage are primarily determined by the building’s location relative to the fault trace. Structures located entirely on the hanging wall exhibited tilting angles that remained below the specified code limit throughout the dislocation process, demonstrating behavior dominated by rigid-body translation. In contrast, buildings crossing the fault exceeded this limit even at low dislocation levels, developing significant tilt and strain concentration due to differential foundation settlement. The most severe damage occurred in high-angle dip sand sites, where the maximum structural tilt reached 5.5°. This research elucidates the phased evolution of seismic damage in straddle-fault structures, providing experimental evidence and theoretical support for the seismic design of buildings in near-fault regions. The principal theoretical and methodological contributions are (1) developing a systematic “fault–soil–structure” testing methodology that reveals the propagation of fault dislocation through the system; (2) clarifying the distinct failure mechanisms between straddle-fault and hanging-wall structures, providing a quantitative basis for targeted seismic design; and (3) quantifying the controlling influence of fault dip angle and soil type combinations on structural damage severity, identifying high-angle dip sand sites as the most critical scenario. Full article

Macroprudential policy, as an important instrument for counter-cyclical regulation, plays a crucial role in enhancing urban economic resilience. Based on this, this paper empirically examines the influence of macroprudential policy on urban economic resilience and its optimization paths using data from 284 prefecture-level cities in China from 2011 to 2023. The research findings indicate that macroprudential policy significantly enhances urban economic resilience, and the conclusion still holds after various robustness tests. Further analysis reveals that the main transmission channels include stimulating digital finance development, promoting industrial structure upgrading, and deepening regional integration. Notably, this effect is particularly pronounced in smart cities, big data pilot zones, and cities with less fiscal pressure. Additionally, the test results of spatial spillover effects show that the direct effect of macroprudential policy on the economic resilience of cities is relatively significant, while the indirect effect is relatively weak. Finally, empirical tests have proved that the improvement of urban economic resilience can further drive regional innovation capability. This study provides empirical support and theoretical references for improving China’s “dual-pillar” regulatory framework and enhancing urban economic resilience. Full article

Shield tunneling beneath existing railways remains a critical challenge in urban infrastructure development, as it risks destabilizing overlying soil structures and compromising railway safety. This study presents an integrated methodology combining physical model tests and three-dimensional numerical simulation, validated by their mutual agreement, to capture the settlement and deformation induced by twin shield tunneling beneath an operational railway under the complex geological conditions of the Qingdao Metro. A parametric study was subsequently conducted to systematically evaluate the influence of critical construction parameters, including grouting pressure, grout stiffness, and chamber pressure, on railhead settlement. Additionally, a comparative analysis assessed the effectiveness of settlement control measures, including D-type beam reinforcement, deep-hole grouting reinforcement, and their combined application. Results show that railhead deformation primarily manifests as settlement, with cumulative effects from sequential tunneling of the left and right lines. Proximity to fault zones intensifies crown subsidence, while tunneling induces significant soil stress relaxation, particularly in geologically weaker strata. Within optimal ranges, increased grouting pressure, chamber pressure, and grout stiffness effectively reduce railhead settlement; however, their efficacy diminishes beyond specific thresholds. The combined D-type beam and deep-hole grouting reinforcement scheme proved most effective in controlling settlement, ensuring railway operational safety and construction stability. These findings provide essential theoretical and practical guidance for optimizing shield tunneling strategies in complex urban environments, enhancing the safety and reliability of critical railway infrastructure. Full article

Historic urban cores face escalating pressures from climate change, rapid urbanization, and uncoordinated redevelopment, which often threaten their cultural identity and social cohesion, demanding innovative solutions that balance heritage conservation with contemporary housing needs. This study introduces an integrated evaluation framework encompassing 18 criteria across architectural, urban, and green dimensions to assess adaptive housing interventions in urban heritage contexts. Building on resilience theory, urban living, and sustainable urban futures, the paper traces the historical and contemporary design influences that have shaped urban housing design in Damascus, and investigates strategies to maintain prospective housing identity by applying the methodology of the developed framework to three representative dwellings in Damascus’s UNESCO-listed city. Considering the heritage-specific indicators, social place memory, and the cultural significance—with environmental performance and socio-economic viability—the developed compass-like tool in this research visualizes multi-criteria scores to identify leverage points for resilience. Results highlight priority zones for intervention and suggested policy incentives. Through the provision of a flexible, clear tool grounded in adaptive housing concepts, this study empowers planners, conservationists, and communities to develop sustainable, forward-thinking approaches for historic urban environments globally. Full article

An in-depth and comprehensive evaluation of carbon emission efficiency (CEE) is essential for promoting high-quality development and achieving the “dual-carbon” goals. This study applies a super-efficiency slacks-based measure (Super-SBM) model with carbon emissions treated as an undesirable output to measure provincial CEE and the Malmquist–Luenberger (ML) index across 30 provinces and major comprehensive economic zones in China from 2010 to 2023. Efficiency trends for 2024–2025 are projected using a hybrid Autoregressive Integrated Moving Average (ARIMA)–Long Short-Term Memory (LSTM) approach. Furthermore, CEE patterns are examined at both national and regional levels, and the relationships between CEE and potential drivers are analyzed using Tobit regressions. Combining the regression outcomes with short-term forecasts, this study provides a forward-looking perspective on the evolution of CEE and its associated factors. The results indicate that (1) China’s CEE demonstrates a generally fluctuating upward trajectory, with the southern coastal and eastern coastal regions maintaining the highest efficiency levels, while other regions remain relatively lower. (2) The temporal changes in CEE across economic zones correspond to variations in technical efficiency and technological progress, with the latter contributing more prominently to overall improvement. (3) CEE shows significant associations with multiple factors: population density, economic development, technological advancement, government intervention, and environmental regulation are positively associated with efficiency, whereas urbanization tends to correlate negatively. Based on these findings, policy implications are discussed to promote differentiated pathways for enhancing CEE across China’s regions. Full article

The Energy–Economy–Environment (3E) nexus within basin economic zones has received significant scholarly attention. As a major river basin economic belt in China, the Yangtze River Economic Belt (YREB) serves as an important case for examining the status and drivers of coordinated 3E development. The findings of this study may also offer valuable insights for promoting sustainable development in river basin economies globally. Encompassing 11 provinces and municipalities, the YREB represents not only a vital socioeconomic region in China but also one of the nation’s largest energy consumers, facing considerable environmental pressures. Using panel data spanning 2009–2019, this study applies the coupling coordination degree (CCD) model, spatial Durbin model, and Moran’s I to assess the coordination level of the 3E system in the YREB. The main findings are as follows: (1) The CCD demonstrated a trend that was fluctuating but generally on the rise throughout the study period. Higher values were observed in eastern provinces and lower ones in western provinces, which reveals a distinct east–west spatial gradient. (2) A significantly positive spatial correlation was observed in provincial 3E coordination, although this correlation fluctuated and showed a slowly weakening trend over time. Local spatial clustering patterns also shifted, marked by the persistence of high-high clusters, an increase in low-low clusters, and the emergence of low-high outliers. (3) Estimates from the spatial Durbin model indicate that urbanization, automobile consumption, and foreign trade exert positive overall effects on the CCD, whereas industrial structure exerts a negative overall effect. Environmental policy is not statistically significant in the static model but shows a negative overall effect when the CCD is lagged by one period. Full article

Spatial mismatches between ecosystem services and human demands pose critical challenges for sustainable land use in ecologically fragile regions. Rapid urbanization intensifies land-use conflicts in ecologically fragile regions, threatening ecosystem services and habitat sustainability. This study addresses this challenge by quantifying spatial mismatches between landscape resource functions (LRFs: natural, traditional, and humanistic) and service demands (LSFs, e.g., catering and public facilities) in Xinxian County, in China’s Dabie Mountains, using multi-source data (DEM, POI big data, and remote sensing) and spatial analysis (nearest neighbor indices, kernel density, and multi-ring buffers). The results reveal that concentrated natural LRFs in high-elevation single-core clusters exhibit low dispersion, thus increasing vulnerability to land conversion, while agglomerated LSFs in urban cores exacerbate ecosystem service inequalities. Crucially, service deficits beyond 3 km buffers and the fragmentation of traditional agricultural zones indicate potential erosion of regulating services, as inferred from spatial mismatches (e.g., soil retention and water regulation), and cultural resilience. These spatial mismatches act as proxies for habitat risks, in which humanistic landscape expansion competes with ecological corridors, amplifying fragmentation. To mitigate risks, we propose (1) enhancing connectivity for natural resource corridors to stabilize regulating services, (2) reallocating LSFs to peri-urban buffers to reduce pressure on critical habitats, and (3) integrating ecosystem service trade-offs into landscape planning. This framework provides an actionable pathway for balancing development and habitat conservation in mountainous regions undergoing land-use transitions. Full article

The Island of Unguja in Zanzibar (Tanzania) has experienced an accelerated urban development growth since the 1990s due to a rapidly increasing population. These rapid land demands put additional stress on the country’s ability to plan urban centers, cities, and the management of natural resources. The study aimed to determine the impact of urbanization on groundwater availability in the catchment area of the Masingini–Mwanyanya forest reserves from 1992 to 2022. The study used a detection approach to determine the Land Use Land Cover (LULC) changes for three decades, starting from 1992 to 2022. Landsat remote sensed images of 1992, 2002, 2012, and 2022 were used. Additionally, a paired t-test was conducted to determine the significant changes in mean population growth, urbanization, and humidity. The aquifer recharge evolution analysis was conducted using the QGIS software (3.34.8 released version). Obtained results revealed that for these three decades, the forest areas decreased by 14.5% (i.e., from 8.3 km² in 1992 to 7.1 km² in 2022), while built-up area increased from 0 km² in 1992 to 1.7 km² in 2022. Moreover, the evolution of undesirable Land Use Land Cover (LULC) changes, particularly the persistent conversion of forested areas into built-up zones, has been detected. This trend poses a significant threat to the sustainable management of water resources and catchment forest reserves. The study also indicated a decline in the recharge of the coastal aquifer supplying Zanzibar City, which decreased from 15.5 Mm³ to 11.1 Mm³. These findings highlight that the Masingini Forest Reserve is increasingly encroached by rapid urbanization, which is a phenomenon that may jeopardize the availability and sustainability of groundwater resources in the catchment without proper urban planning. Based on these results, the study recommends further research and upscaling of the existing findings, as well as collaboration with relevant authorities to redefine the Masingini–Mwanyanya forest catchment area to ensure the sustainable use of groundwater resources. Full article

Under the context of global climate change and China’s dual carbon strategy (DCS), the impact of land use/land cover change (LULCC) on regional carbon stocks has garnered increasing attention. As a key economic and ecological hub in Southwest China, Chengdu has undergone significant urbanization over the past two decades, and it is necessary to quantitatively assess how shifts in land use affect its carbon stock function. This study integrates multi-period remote sensing data from 2000 to 2020, combining socioeconomic and natural environmental drivers. The PLUS model was employed to simulate land use in 2030 under four scenarios: Natural Development Scenario (NDS), Urban Development Scenario (UDS), Conservation of Cropland Scenario (CPS), and Ecological Protection Scenario (EPS). The InVEST model was then used to calculate changes in carbon stocks and their spatial distribution characteristics. The results indicate the following: (1) From 2000 to 2020, Chengdu’s cropland decreased by 1188.6174 km², while built-up land increased by 1006.5465 km², resulting in a net carbon stock decrease of approximately 3.25 × 10⁶ t, with carbon gains from forest restoration offsetting part of the cropland-to-built-up loss; (2) Under all scenarios, built-up land exhibited an expansion trend, with the UDS showing the most significant increase, reaching 1919.2455 km². In the EPS, the forest increased to 4035.258 km², achieving the largest carbon stock increase of 8.5853 × 10⁶ t. (3) Chengdu’s carbon stock exhibits a spatial distribution pattern characterized by “high in the northwest, low in the center”. High-value areas are concentrated in the ecologically sound Longmen Mountains and Longquan Mountains, while low-value areas are primarily located in urban built-up zones and their peripheries. The study indicates that rationally controlling the expansion of Built-up land, strengthening ecological restoration, and protecting forests can effectively enhance Chengdu’s carbon sink capacity and achieve regional low-carbon and sustainable development. This study aims to address the gap in carbon stock assessments under different development scenarios at the urban scale in Southwest China, and to provide a scientific basis for Chengdu’s regional spatial planning, ecological conservation, low-carbon development, and sustainable land management. Full article

This study addresses the critical challenge of balancing coastal wetland conservation with urban sustainable development, a pivotal issue for ecological civilization in rapidly developing regions. Through an in-depth analysis of Qingdao and Weihai—exemplary cases in Shandong Province—this research systematically investigates mechanisms for achieving synergistic win–win outcomes. Employing a mixed-methods approach, including systems analysis to deconstruct governance frameworks, comparative case study to identify transferable strategies, and policy deduction to formulate actionable pathways, the study reveals how integrated approaches yield tangible results. Qingdao’s “Five Ocean Usages” concept and Weihai’s segmented coastal zoning have significantly improved key ecological metrics. By contrast, Qinhuangdao faces pronounced challenges, including degraded wetlands, spatial conflict between ports and core habitats, and underdeveloped synergistic governance. To address these, the study proposes a targeted strategy for Qinhuangdao, emphasizing a data-informed “wetland+” multi-format integration plan, the establishment of wetland mitigation banking and green finance instruments, digitally enabled public participation, and deeper policy alignment with national strategies such as Maritime Power. This research provides both a replicable analytical framework and practical guidance for coastal cities seeking to realize “development within protection and protection within development”. Full article

Driven by the “dual-carbon” strategy, the development of zero- and low-carbon parks has become a crucial approach to resolving the conflict between urban expansion and ecological limits. Using urban functional zoning and land use data, this study estimates carbon emissions in Xiamen and examines their spatial distribution at the functional zone level, along with an assessment of carbon balance zoning. The results indicate that (1) Carbon sources far exceed sinks, with spatial concentrations in southern and northern areas, respectively. Commercial, transportation, and industrial zones are major emission sources. (2) A significant negative spatial correlation in carbon emissions exists among functional zones, manifesting as an alternating pattern of high- and low-carbon zones. (3) 72% of the zones have an ecological support coefficient below one, indicating severe carbon imbalance. (4) Xiamen can be categorized into four carbon balance functional zones, with carbon-source regulation zones accounting for 70%, core carbon-source zones accounting for 5%, and carbon-sink stressed zones accounting for 25%. No core carbon sink zones are identified. Based on these findings, targeted strategies are proposed: ecological restoration in northern Xiamen, carbon emission regulation in central areas, and source reduction in the south. These measures provide a scientific foundation for supporting Xiamen’s low-carbon transition and sustainable development. Full article