Urban agglomeration is a highly developed spatial form of integrated cities. It occurs when the relationships among cities shift from mainly competition to both competition and cooperation. Cities are highly integrated within an urban agglomeration, which renders the agglomeration one of the most important carriers for global economic development. Studies on urban agglomerations have increased in recent decades. In the research community, a consensus with regard to what an urban agglomeration is, how an urban agglomeration is delineated in geographic space, what efficient models for urban agglomeration management are, etc. is not reached. The current review examines 32,231 urban agglomeration-related works from the past 120 years in an attempt to provide a theoretically supported and practically based definition of urban agglomeration. In addition, through this extensive literature review and fieldwork in China, the current research identifies the four stages of an urban agglomeration’s spatial expansion and further proposes operable approaches and standards to define urban agglomerations. The study aims to provide a scientifically sound basis for the healthy and sustainable development of urban agglomerations.
Environmental regulations affects the environmental quality of not only local areas but also surrounding regions. It remains unknown whether the effect of environmental regulations on the surrounding regions is free riding or pollution shelter. Based on the data from 2006 to 2018, the spatial correlation of PM2.5 in Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD) and Pearl River Delta (PRD) urban agglomerations in China was examined in this study. In addition, the spatial spillover effects of environmental regulation on PM2.5 concentrations were explored while the socio-economic driving factors of the heterogeneity of pollution spillover were identified via SDM based STIRPAT framework. Results showed that the characteristics of PM2.5 concentrations spatial correlations varies from one urban agglomeration to another. This study revealed that the air pollution is affected by not only local environmental regulations, but also regulations implemented in surrounding cities. The PM2.5 concentration of BTH, YRD and PRD increased by 0.76, 0.147 and 0.109 for each unit increase in environmental regulation of surrounding cities, respectively. In fact, cities with loose regulation become the pollution shelters. The spatial spillover effects offset the improvement effects of local environmental regulations on the air quality. Furthermore, the comparison amongst three urban agglomerations showed that the spatial spillover effects of PM2.5 concentration in BTH and YRD are higher than that of PRD. This is attributed to differences in industrial structure, population density, economic development, FDI and geographical location. Therefore, the spatial spillover effects should be taken into consideration and joint regulation should be strengthened to address air pollution issues in urban aggregations.
Abstract Performance-based planning (PBP) is designed to determine city planning standards based on local activity characteristics; however, there have been few practical applications of this method. This study applied PBP to assess the impact of urban building morphology on local climate surface temperatures under different wind conditions during 2017 in Shanghai, China using multi-source data, such as frontal area density (FAD), local climatic zone classification, land surface temperature (LST) data, and geographic information. The results showed that urban architectural patterns were one of the important drivers of climate change. High-density high-rise buildings can increase surface temperatures, which were evidenced in Local Climate Zone 4 (LCZ4), LCZ7, and LCZ8 in the city center. A correlation between building FAD and local climate surface temperature was 0.44 during the winter. Also, we found that although seasonal differences affected by wind direction were small, the same wind had different effects on the surface of urban buildings in different climate zones. These findings provide a reference for urban architecture planning and can help to develop urban heat island adaptation strategies based on local conditions.
Abstract Noise pollution is a growing challenge for public health and livability in Greater Cairo. This study develops a calibrated framework for noise-sensitive land use planning by integrating field measurements,morphological analysis, and dual simulation tools (Predictor-LimA and Autodesk Forma). Case studies in Sheraton Heliopolis, New Cairo, and El Shorouk reveal noise hotspots, receptor vulnerabilities, and land-use conflicts. Unlike conventional noise mapping, the framework links empirical data with simulation outputs to produce quantitative conflict scores and receptor-sensitivity maps, enabling planners to embed acoustic resilience into zoning and design decisions. The contribution lies in bridging applied acoustics with urban planning and governance, positioning acoustic comfort as a principle of environmental justice and livability. Recommendations—such as façade orientation, vegetative buffers, and zoning amendments—are presented as evidence-based interventions derived from measured exceedance zones rather than prescriptive best practices. The results demonstrate how integrating acoustic criteria into land use policy can foster healthier, more equitable urban environments and provide a replicable model for rapidly urbanizing cities.
Cities. Urban geography, Urban groups. The city. Urban sociology
Abstract Urban green and blue infrastructure (GBI) and associated ecosystem services (ES) are increasingly recognized for their potential to address urban sustainability challenges. This has resulted in an increase in studies quantifying ES in cities. In this review, we analysed 850 peer-reviewed publications to characterize urban ES assessment in terms of geographical location, urban GBI type and methodological aspects (e.g. ES indicators). The analyses covered six ES: local temperature regulation, stormwater regulation, waste treatment, air quality regulation, pollination, and recreation and aesthetic appreciation. The majority of ES assessments focused on local temperature regulation (36%) and recreation and aesthetic appreciation (23%) and assessments were often conducted within unspecified green space (30%) and parks (26%). A common method to assess GBI performance was the comparison of ES delivery along a gradient of vegetation cover (24%). Moreover, assessments used a wide variety of ES indicators. Most assessments quantified ecosystem properties (59%), while a minority assessed actual benefits to people, recognized values or societal demands. To advance insights in the effectiveness of GBI, we recommend increased research attention towards i) increasing the coverage of less studied ES, GBI types and geographical regions, ii) quantifying actual benefits of GBI by comparing ES supply and societal demand, and iii) comparing effectiveness across different GBI types and in relation to grey infrastructure.
A vigorous debate has emerged in recent years over how to understand cities of the Global South. A pivotal issue in this debate is whether urbanisation processes in the South are so fundamentally different from historical and current urbanisation in the Global North that many of the theories developed from studying the latter have limited utility in application to the former. In this article, we review evidence from a range of disciplines on recent and ongoing urban transitions and urbanisation dynamics in the Global South, attending to features that distinguish the urban South from the urban North. Our reading of the evidence indicates that parts of the Global South may be urbanising along historically and geographically specific trajectories; however, we argue that these differences are best understood through a unified set of global urban theories. Rather than flattening or silencing difference, theories that seek generalisation across time and space sharpen the identification and appreciation of key differences in urbanisation processes. Analysing how the fundamental dynamics of urbanisation recombine and interact with one another in different contexts offers insight into policy challenges that cut across cities, both within and between the Global South and North, as well as context-specific policy issues that arise through the interaction of global urbanisation forces and local specificities.
Many cities in the world have developed metro systems. Metro systems affect urban development in many ways, such as enhancing labour force mobility, increasing urban productivity and promoting urban underground space (UUS) utilisation to accommodate urban functions. This paper explores the relationship between metro systems and urban development, with particular focus on the comprehensive impacts of metro development on the economic, environmental and social development of cities. The contribution of metro systems to urban development has been confirmed by numerous studies in many cities in the world. The positive capitalisation of metro systems is reflected in property values in areas surrounding metro systems, although the impacts may vary spatially, temporally and geographically. In addition, metro systems impact on the natural and built environments by reducing air pollution and greenhouse gas emissions, encouraging new development and urban renewal, sharping urban development and land use, facilitating commercial growth and residential development, promoting the utilisation of UUS, and increasing mixed land use and urban density. However, there are mixed effects, both positive and negative, of metro systems on equality of transit opportunity, accessibility and connectivity, public health, travel behaviour, personal identity, travel experience and safety. This study sheds light on the impacts of metro systems on urban development, and provides important information for urban and transport planners and policy-makers wishing to develop metro systems to support sustainable urban development.
Circular economy (CE) is gaining popularity at different levels with the promise of creating more sustainable processes. In this context, cities are implementing a number of initiatives that aim to turn them into sustainable circular systems. Whether these initiatives achieve their sustainability goals, however, is largely unknown. Nevertheless, as the application of CE strategies is actively encouraged by many policies across the globe, there is a need to quantify the environmental impacts and to identify the strategies that support urban sustainability. This paper analyses the extent to which research focuses on quantifying the environmental balance of CE initiatives promoted at the municipal level. To this end, the analysis scanned CE initiatives reported in cities around the globe and classified them into urban targets and CE strategies. In parallel, the paper conducted a review of the literature that uses industrial ecology tools to account for the environmental impacts of CE strategies. Results show a diverse geographical representation, as reported cities concentrated in Europe, whereas for environmental research, the main results came from China. In general, cities encourage strategies relating to urban infrastructure (47%), with and additional focus on social consumption aspects, such as repair and reuse actions. In comparison, research mainly addressed industrial and business practices (58%), but the approach to infrastructure was similar to that of cities, both with a special interest in waste management. Research has yet to assess social consumption and urban planning strategies, the latter essential for defining the impacts of other urban elements. Hence, there is a need to define the environmental impacts of the strategies that cities select in their quest for circularity. Research and practice can also benefit from working collaboratively so as to prioritize the CE strategies that best fit into the features of each urban area.
Abstract This study presents a comprehensive analysis of flood hazard mapping in Ankara, the capital of Türkiye, highlighting the critical vulnerability of this major urban center to climate-related disasters. By applying advanced boosting algorithms—specifically, XGBoost, GradientBoost, and CatBoost—along with hyperparameter optimization through the Fick’s law algorithm (FLA), this research introduces an innovative methodology aimed at improving the reliability and accuracy of flood hazard assessments in Ankara’s urban landscape. The analysis utilizes an extensive dataset that integrates topographic, meteorological, hydrological, and anthropogenic variables to provide critical insights into the dynamics of urban flooding with a focus on Ankara’s vulnerability. This approach is novel in that it incorporates FLA for hyperparameter optimization, marking a significant advancement in flood hazard modeling and achieving higher model accuracy and generalizability. Notably, among the various determinants of flood hazard identified, elevation emerges as the most influential factor affecting flood risk in Ankara. This finding underscores the complex relationship between urban geography and flood hazards, and highlights the need for targeted urban planning and infrastructure development strategies to effectively mitigate flood risk. The implications of this research extend beyond the local setting, contributing valuable insights to the global discourse on climate change adaptation and urban resilience. By combining cutting-edge machine learning techniques with in-depth geographic analysis, this study offers a scalable and innovative model for flood hazard assessment and management, providing a critical tool for cities around the world facing similar challenges.
Tidarut Jirawattanasomkul, Le Hang, Supasit Srivaranun
et al.
This study developed a digital twin (DT) and structural health monitoring (SHM) system for a balanced cantilever bridge, utilizing advanced measurement techniques to enhance accuracy. Vibration and dynamic strain measurements were obtained using accelerometers and piezo-resistive strain gauges, capturing low-magnitude dynamic strains during operational vibrations. 3D-LiDAR scanning and Ultrasonic Pulse Velocity (UPV) tests captured the bridge's as-is geometry and modulus of elasticity. The resulting detailed 3D point cloud model revealed the structure's true state and highlighted discrepancies between the as-designed and as-built conditions. Dynamic properties, including modal frequencies and shapes, were extracted from the strain and acceleration measurements, providing critical insights into the bridge's structural behavior. The neutral axis depth, indicating stress distribution and potential damage, was accurately determined. Good agreement between vibration measurement data and the as-is model results validated the reliability of the digital twin model. Dynamic strain patterns and neutral axis parameters showed strong correlation with model predictions, serving as sensitive indicators of local damage. The baseline digital twin model and measurement results establish a foundation for future bridge inspections and investigations. This study demonstrates the effectiveness of combining digital twin technology with field measurements for real-time monitoring and predictive maintenance, ensuring the sustainability and safety of the bridge infrastructure, thereby enhancing its overall resilience to operational and environmental stressors.
Disasters and engineering, Cities. Urban geography
Urban parks are essential components of urban ecosystems, providing recreation and relaxation places to residents. Measuring the spatial accessibility to urban parks serves as an initial step in urban planning and developing urban development strategies to improve social and environmental justice. This study aims to evaluate measures of spatial accessibility to urban parks by comparing three geographic information systems (GIS)-based approaches, accounting for network complexity, transport modes, distance thresholds, and destination choices. Taking Ipswich City (Australia) and Enschede (the Netherlands) as two testbeds, we examine the spatial patterns of a total of 21 accessibility measures in the two cities and conduct a correlation and principal component analysis to unravel the interrelationship between these measures. The results suggest that among all measures under the three approaches, the selection of distance thresholds and transport modes matter more to accessibility measures than the destination choices. Furthermore, when distance threshold and transport mode are held constant, the network-based and entrance-based methods provide more realistic accessibility measures than other methods. We also discuss the generality of the entrance-based method we propose and suggest ways to choose the most appropriate accessibility measure for use in different contexts.
Abstract Rapid urbanization is one of the present characteristics in both developed and developing countries. It is projected that by 2050 around 68 % of the world’s population shall live in urban areas. As a result, many city development initiatives are proposed by various research centers or through academia to aid in managing the process. One of the most evolving concepts through the past two decades is Smart Cities. The concept of smart cities has been defined and formulated by many research efforts and organizations. However, most of these definitions and initiatives focus on the operation stage of the city. This paper proposes an inclusive framework for integrating Building Information Modeling (BIM) and Geographical Information System (GIS) to plan and forecast the utility infrastructure needs for expanding and emerging cities to highlight the concept of “smartness” during the planning stage. The considered infrastructure needs are freshwater consumption, sewage capacity and electrical energy requirements. Firstly, the city is broken down into several districts, lands and plots. Afterwards, through the assignment of relevant land use, building type information and various other information, an interactive tool is originated to allow for the formulation of different city development schemes and the representation of their respective resulting infrastructure needs. The framework is targeted to be flexible enough in order to be applied to any city, not just a single case as smart city solutions need to adopt to diverse cities’ needs. The proposed framework is advocated to enforce the concept of both smart and sustainable cities by taking a closer look at the city’s planning and development stages and infrastructure requirements which shape a sizable part of the city’s performance throughout its expansion and development. It can also serve as a decision support tool for better planning and management of smart city infrastructure requirements. Finally, a case study is represented to demonstrate the practical features of the proposed framework.
Provinsi D. I. Yogyakarta dikenal sebagai provinsi dengan jumlah pariwisata terbanyak ke dua di Indonesia. Di Provinsi D. I. Yogyakarta terdapat banyak Desa Wisata dan salah satu lokasi yang paling dikenal wisatawan adalah Desa Wisata Pentingsari yang terletak di Dusun Pentingsari, Desa Umbulharjo, Kecamatan Cangkringan, Kabupaten Sleman. Keberhasilan Desa Wisata Pentingsari tidak luput dari keberhasilan masyarakat Dusun Pentingsari dalam mengelola Desa Wisata Pentingsari yang berbasis konsep Community Based-Tourism. Hal tersebut hendaknya mampu untuk dipertahankan di masa depan, mengingat Desa Wisata Pentingsari merupakan salah satu ikon pariwisata yang berbasis nuansa kawasan pedesaan di Provinsi D. I Yogyakarta. Penelitian ini bertujuan untuk menganalisis keberlanjutan Desa Wisata Pentingsari dalam mengembangkan desa wisatanya. Metode penelitian yang digunakan adalah deskriptif kuantitatif dengan pengumpulan data secara primer dan sekunder. Jumlah responden sebanyak 80 orang yang semuanya adalah masyarakat Dusun Pentingsari. Data yang diperoleh kemudian dianalisis menggunakan Multidimensional Scaling (MDS) dengan pendekatan Rap-Tour pada 3 (tiga) dimensi yaitu Ekologi, Ekonomi, dan Sosial. Hasil analisis menggunakan Multidimensional Scaling dengan pendekatan Rap-Tour pada ketiga dimensi menunjukkan indeks keberlanjutan Desa Wisata Pentingsari dinilai cukup berkelanjutan dengan nilai rata-rata dari ketiga dimensi adalah 65,336% pada selang 51-75. Analisis Monte Carlo dengan 25 kali pengulangan menunjukkan bahwa bahwa nilai status keberlanjutan Desa Wisata Pentingsari pada selang kepercayaan 95% didapatkan hasil yang tidak banyak mengalami perbedaan antara hasil analisis MDS dengan analisis Monte Carlo (< 5%).
This paper addresses the scope for action by municipalities in a climate emergency and places it in the framework of ecomodern (urban) policy. We analyse the way in which two German ‘climate emergency municipalities’ translate conflicts of post-fossil transformation into concrete political and planning strategies. Although more than 2,200 authorities around the world have already declared a climate emergency, research on the impact of these resolutions on the political orientation of municipalities is very limited. Our research focus is on the (potentially agonistic) treatment of conflicts in planning. We argue that in times of a socio-ecological crisis, success in conflict resolution cannot refer to appeasement and depoliticisation. Instead, we propose a framework of five criteria, based on critical theory on ecomodern strategies, planning processes and degrowth. Thus, this practice-related and explorative paper connects empirical insights from the German cities of Constance and Berlin with an innovative normative framework. The findings tell a complex story of an, at least partial, admission of the failure of previous climate mitigation strategies, a lack of social institutions of limits, an instrumental relation to nature and a disregard for social injustices. The paper discusses how municipalities, in the context of ongoing tensions over the post-fossil transformation in Germany, on the one hand hold on to business-as-usual approaches, but on the other hand also set political impulses for change.
Cities. Urban geography, Urbanization. City and country