Search Results (1,357)

Accommodation establishments constitute a core component of tourism infrastructure, and their location choices directly affect water resource utilization, land pressure, and the spatial equilibrium of tourism development—issues that are particularly acute in vast arid regions. Yet the spatial organization of accommodation supply across extensive drylands characterized by fragmented oasis distribution, and the reasons why standard and non-standard accommodation follow divergent location logics, remain poorly understood. This study addresses three questions: (1) How are nine accommodation categories, differentiated by type and quality, distributed across Xinjiang? (2) Do directional spatial associations exist among categories that are consistent with hierarchical, path-dependent development? (3) Which factors drive these patterns, and do their effects exhibit the nonlinearity and threshold behavior predicted by location theory? Drawing on 12,073 accommodation establishments from the Ctrip platform, we construct a staged analytical framework in which each technique answers a specific question: the nearest-neighbor index and standard deviational ellipse characterize global patterns; kernel density estimation and OPTICS clustering identify local agglomerations; directional local co-location quotients measure asymmetric spatial associations; and XGBoost–SHAP isolates nonlinear drivers and threshold effects. Results reveal a highly concentrated “single-core, multi-center” structure anchored by Urumqi, Yining, and Kashgar, with rapid expansion toward the Ili Valley, Kashgar, and Altay since 2019. Standard accommodation tracks urban centrality and transport nodes, while non-standard accommodation tracks tourism resource endowments, consistent with location-theoretic expectations. Directional co-location analysis reveals hierarchical spatial associations among categories, and driving factors exhibit pronounced nonlinear threshold effects. From a sustainability perspective, the identified thresholds—elevation (1360 m), water-body proximity, and distance to rural tourism demonstration sites (3 km)—constitute quantifiable, spatially explicit sustainability indicators that can be incorporated into planning tools to monitor and steer accommodation development away from ecologically sensitive zones. Global Moran’s I diagnostics of model residuals (reduction of 83–99.7%) suggest that these findings are unlikely to be artifacts of spatial autocorrelation; this diagnostic, however, complements rather than replaces spatially blocked validation. The study contributes category-differentiated, spatially directed evidence for policies balancing tourism expansion against water security and ecosystem integrity, serving sustainable tourism development in arid-region destinations. Full article

Urban informality in amphibious territories represents a critical yet understudied dimension of contemporary urbanisation in the Global South. This article analyses the interrelations between spatial transformation, social equity, and environmental change in Las Flores, an informal settlement located between the Mallorquín Lagoon and the Magdalena River in Barranquilla, Colombia. Drawing on a mixed-methods approach combining GIS interpretation, participatory mapping, and in-depth interviews, the study examines how processes of informal territorialisation have reshaped both the physical landscape and the social fabric of this amphibious environment. Results indicate that the settlement has expanded progressively over the past two decades, occupying areas of the wetland previously covered by mangroves and natural vegetation. This expansion has been accompanied by environmental degradation, soil infilling, and declining water quality. Residents face persistent infrastructural deficits, limited access to education and healthcare, and increasing social fragmentation between the formal and informal sectors. Yet, the community also exhibits strong organisational capacity, adaptive livelihoods, and a deep sense of place that sustains local identity and resilience. These dynamics exemplify the paradox of amphibious life: coexistence with water as both a resource and a source of vulnerability. Building on these findings, the study develops an urban socio-ecological conceptualisation of Amphibious Justice, a framework for interpreting equity, recognition, and governance in hybrid territories where urbanisation and land–water dynamics intersect. The article proposes a framework of equitable amphibious urbanism that integrates environmental restoration, social inclusion, and participatory governance. The findings suggest that sustainability in such territories cannot be achieved through technocratic restoration or forced resettlement, but through co-produced strategies that recognise local knowledge, tenure security, and ecological stewardship. Ultimately, the case of Las Flores offers insights into how cities in the Global South can pursue just and adaptive coexistence with water amid growing climate and urban pressures. Full article

This study assessed the current status of irrigation systems and water management practices in Rwanda’s irrigated agricultural zones, focusing on the Nasho Government-Funded Irrigation (GFI) scheme in Kirehe District and the Kagitumba Irrigation Scheme in Nyagatare District. A mixed descriptive approach was used, combining field observations with structured questionnaires administered via KoboToolbox to 224 respondents in Nasho and 188 in Kagitumba. Field observations were used to evaluate the physical condition and functionality of irrigation infrastructure, while questionnaires captured stakeholder perceptions, water management practices, institutional arrangements, and operational challenges. Results show that both irrigation schemes are operational but function below optimal efficiency due to multiple constraints. In Nasho, irrigation performance is primarily affected by sedimentation in canals and reservoirs, pump inefficiencies, and inadequate maintenance practices, resulting in unreliable water delivery. In Kagitumba, despite the use of modern center pivot systems, performance is constrained by pipeline corrosion, pressure losses, sediment-laden water, and uneven water distribution. Across both schemes, more than 80% of respondents reported frequent system failures, while over 95% indicated the absence of formal irrigation scheduling practices. Water management remains largely reactive, with limited preventive maintenance and weak technical capacity among users and institutions. The study concludes that improving irrigation efficiency in Rwanda requires integrated interventions that combine infrastructure rehabilitation, strengthened maintenance systems, improved water governance, and farmer capacity development to enhance sustainable water use and agricultural productivity. Full article

Interlocking permeable pavements (IPPs) are increasingly adopted within sustainable urban drainage systems to reduce runoff, improve water quality, and strengthen climate-resilient urban infrastructure. However, clogging remains the principal constraint on their long-term hydraulic performance and wider implementation. This review synthesises current evidence on clogging mechanisms, hydraulic decline, and lifecycle mitigation strategies for permeable interlocking concrete pavements (PICPs), concrete grid pavements (CGPs), and plastic grid pavers (PGPs). The literature is dominated by PICP studies, with CGP and PGP underrepresented, restricting typology-specific assessment. Sediment accumulation within joints, grid openings, bedding layers, and near-surface interfaces is consistently identified as the primary clogging mechanism, while traffic, rainfall-runoff loading, biological processes, pollutant retention, and sediment inputs from adjacent impervious surfaces further influence hydraulic deterioration. The findings indicate that hydraulic performance is influenced not only by pavement age but also by interactions among pavement design, filler or joint material, drainage configuration, construction quality, sediment exposure, monitoring, and maintenance. Effective mitigation therefore requires lifecycle management, encompassing source control, pretreatment, appropriate material selection, construction quality assurance, routine hydraulic monitoring, and timely preventive and restorative maintenance. Future research should prioritise standardised clogging assessment protocols, improved laboratory–field integration, targeted investigation of CGP and PGP, biological and pollutant-linked clogging processes, climate-driven rainfall extremes, and decision-support. Full article

Historic urban landscapes are at continuous risk of loss due to urban modernization and the demolition of built heritage. Scan-based documentation methods such as laser scanning and photogrammetry become inapplicable, leaving demolished sites undocumented and unrecoverable through existing digital heritage workflows. This study develops a documentary-based Urban Digital Twin (UDT) framework for reconstructing demolished historic urban landscapes through the integration of historical documentation, geospatial analysis, and parametric modeling within the Historic Urban Landscape (HUL) approach. As a feasibility study, the framework reconstructs Chahar-Bagh Bala Street in Isfahan, Iran, a four-century-old promenade among the oldest urban streets in the Middle East, whose royal garden entrances, towers, water features, and promenade have been almost entirely replaced by industrial and modern structures. The methodology applies a nine-step workflow, integrating georeferencing, viewpoint reconstruction, cross-source validation, and HBIM parametric modeling, using historical maps, travel account engravings, archival photographs, and measured plans. The reconstruction confirms the historical existence and spatial locations, established through convergent visual evidence, of two lost royal garden entrances. The study further quantifies long-term historic green infrastructure loss, finding that approximately 70% of the original garden cover has been replaced. This replicable framework supports evidence-based heritage governance and sustainable urban regeneration, including the reintegration of historic green infrastructure into contemporary urban planning, particularly for rapidly transforming cities of the Global South. Full article

Contemporary approaches to urban water management increasingly rely on concepts such as Nature-Based Solutions (NBSs), Green Infrastructure, and Blue-Green Infrastructure. Although these frameworks have gained broad acceptance, their typological character provides limited guidance for project-oriented decision-making, as they primarily describe infrastructure types rather than their functions within integrated hydrological systems. To address this gap, this study proposes a complementary functional-operational framework for interpreting ecological infrastructures in urban flood mitigation. Employing a qualitative comparative case study methodology, we analysed four diverse international models—the Dutch Water Squares (Rotterdam), Tokyo’s underground flood control system, Copenhagen’s Cloudburst Management Plan, and Singapore’s ABC Waters Programme—to examine the systemic interaction between grey, green, and blue infrastructures at different watershed scales. The results indicate that flood mitigation effectiveness depends less on the predominance of a single infrastructure type and more on the functional coupling among them. Specifically, three primary functions were identified: rapid conveyance (grey infrastructure), infiltration and thermal regulation (green infrastructure), and dynamic storage and biodiversity support (blue infrastructure). Despite the contextual limitations and varying scales of the selected cases, blue infrastructure universally emerges as a systemic buffer that enhances urban resilience by regulating excess volumetric flows. Ultimately, the proposed framework introduces an actionable interpretative layer that complements existing typological classifications, providing planners and urban designers with a robust, scalable basis for implementing integrated ecological infrastructures. Full article

Rapid urbanization and inadequate sanitation infrastructure threaten water security in many sub-Saharan African cities. This study aimed to provide an integrated assessment of groundwater, surface water, and wastewater quality in Bangui by characterizing physicochemical parameters, trace metals, and microbiological indicators, and by identifying potential contamination sources and pathways among these water compartments. A total of 28 water samples were collected from groundwater, surface water, and wastewater sites. Physicochemical parameters, major ions, trace metals, and microbiological indicators were analyzed using standardized methods, including ion chromatography, ICP-OES, ICP-MS, and membrane filtration. Results revealed a clear contamination gradient. Wastewater showed the highest electrical conductivity, turbidity, chloride concentrations, and microbial loads, reaching 2.41 × 10⁶ CFU/100 mL for total coliforms and 1.93 × 10⁶ CFU/100 mL for fecal coliforms. Groundwater exhibited high nitrite levels and low dissolved oxygen, indicating vulnerability to sewage infiltration. Surface waters were characterized by high turbidity and widespread fecal contamination despite relatively good oxygenation. In contrast, trace metal concentrations generally remained below World Health Organization guideline values. Geochemical analyses identified distinct elemental signatures for each water type. Microbiological contamination emerged as the dominant water quality concern. High fecal coliform/fecal streptococci ratios (13.08-22.16) indicated predominantly human-derived pollution linked to untreated wastewater and inadequate sanitation systems. The association between elevated nitrite concentrations and fecal indicators suggests active contamination pathways connecting wastewater, surface water, and shallow aquifers. These findings highlight the urgent need for improved wastewater management, groundwater protection, and long-term monitoring to ensure sustainable urban water security in Bangui. Full article

Understanding river channel evolution is essential for effective management, as lateral erosion shapes riverbeds, floodplains, and riparian habitats. Despite advancements in remote sensing, translating these technologies into operational tools for institutional monitoring remains a challenge. This study introduces a semi-automated framework designed to bridge this gap by quantifying lateral mobility and bank retreat rates in high-energy, gravel-bed rivers. The methodology utilizes a Random Forest classifier applied to Copernicus Sentinel-2 time series (2016–2024) across five rivers in Piedmont (Italy). By detecting pixel-level class shifts between water, vegetation, and sediment, the procedure provides a proxy for lateral mobility. Validated against 120 km of manual delineations, the model achieved high spatial accuracy for both bank retreat rates and eroded bank lengths measurements (Mean Absolute Deviation of 2.64 m/yr and 4.34%, respectively). Integrating discharge data and the hydraulic infrastructure cadaster of the Sesia River, the proposed framework effectively detects reaches prone to significant geomorphic changes, isolates their underlying drivers, simulates 10-year evolutionary trajectories, and demonstrates strong predictive capabilities regarding future channel–infrastructure interactions. This study marks a shift from sporadic, labor-intensive assessments to a dynamic, systematic monitoring framework. Leveraging free satellite data, it provides competent authorities with an objective, cost-effective tool to prioritize interventions, supporting flood risk reduction and river restoration. Full article

Expansive soils are rich in hydrophilic clay minerals, and repeated wetting–drying cycles can induce deformation that threatens infrastructure safety. Therefore, accurate monitoring of soil moisture (SM) dynamics is essential for understanding hydro-mechanical processes and assessing related geohazards. In this study, spaceborne Global Navigation Satellite System Reflectometry (GNSS-R) is applied to expansive SM monitoring, and an Attention-Enhanced Spatio-Temporal Graph Convolution Network (ASTGCNet) is proposed for SM retrieval. The Texas coastal region, where Beaumont clay is widely distributed, was selected as the study area. The ASTGCNet-derived SM showed consistency with the Soil Moisture Active Passive (SMAP) reference product, with an overall correlation coefficient of 0.92, an RMSE of 0.035 m³/m³, and a bias of 0.006 m³/m³. Validation against in situ observations showed that ASTGCNet provided more accurate SM estimates than the Cyclone Global Navigation Satellite System (CYGNSS) L3 SM product. Extended triple collocation analysis further indicated that ASTGCNet achieved the lowest standard deviation of 0.020 m³/m³ and the highest signal-to-noise ratio of 7.33. Compared with non-expansive soils, expansive soils exhibited stronger water absorption and moisture retention behavior. By integrating GNSS vertical displacement observations, the retrieved SM revealed a nonlinear SM–deformation response that was mainly observed in shallow expansive soils. Drying-induced SM decreases corresponded to pronounced subsidence, while subsequent wetting led to ground rebound; this behavior was not clearly observed in non-expansive soils. This study demonstrates the potential of GNSS-R for expansive SM monitoring and provides new insights into the coupling between SM dynamics and deformation. Full article

Climate change increasingly threatens Mediterranean ornamental horticulture and green infrastructure through elevated temperatures, prolonged drought conditions, soil salinity, and more frequent extreme weather events. As a result, plant growth, phenology and landscape sustainability are significantly affected. This systematic review aimed to identify and qualitatively synthesize the available evidence on the responses of ornamental plants and their production and end use systems to climate-related stress, with emphasis on Mediterranean native species and their potential contribution to climate-resilient landscaping. The review was conducted and reported in accordance with PRISMA 2020. An adapted Population–Exposure–Outcome framework was used to operationalize the overarching review question and guide eligibility assessment. Scopus and the Web of Science Core Collection were systematically searched for peer-reviewed English-language articles published between 1 January 2001 and 31 May 2026. Eligible publications examined ornamental plants, floricultural species, or native and endemic taxa with potential ornamental or landscape use and addressed climate-related stressors, plant resilience, adaptation strategies, cultivation or propagation practices, green-infrastructure applications, or related ecological trade-offs in Mediterranean-relevant contexts. Two reviewers independently assessed titles, abstracts, and full texts using predefined eligibility criteria. The review used a structured qualitative narrative synthesis organized into thematic domains to systematically identify, select, and synthesize the available evidence. Meta-analysis was not undertaken because of substantial heterogeneity in plant material, environmental stressors, study designs, and reported outcomes. A total of ninety studies were included and organized into five domains: climate stress and plant responses (n = 14), native Mediterranean ornamental species (n = 21), adaptation and resilience strategies (n = 16), urban landscaping and green infrastructure (n = 25), and ecological risks and invasive species (n = 14). The review revealed that several native Mediterranean plants possess morphological, physiological, or ecological characteristics associated with tolerance to drought, salinity, and other climate-related stresses, supporting their potential use in sustainable ornamental horticulture. Water-efficient irrigation, alternative water sources and substrates, nursery preconditioning, non-microbial biostimulants, and genotype or physiological screening showed adaptation potential, but their effectiveness depended on species, genotype, intervention intensity, and application context. Evidence remained limited for compound stresses, combined interventions, nursery-to-landscape transfer, long-term field performance, commercial scalability, and environmental trade-offs. Overall, climate-resilient ornamental horticulture requires the integration of plant selection, propagation, production, controlled stress screening, landscape validation, and ecological-risk assessment. This review proposes an evidence-to-application framework to support research, nursery production, landscape planning, and the responsible deployment of climate-adapted ornamental plants. Full article

The global plastic pollution crisis demands a fundamental re-evaluation of materials systems beyond incremental improvements to fossil fuel-based polymers. Bioplastics, polymers derived from renewable biological feedstocks, biodegradable under defined conditions, or both, offer a chemically diverse and rapidly evolving platform for transitioning toward circular materials economies in which the value of carbon, energy, and material is retained across multiple use cycles. This review provides a comprehensive and critically organized account of the bioplastics field, spanning three generations of feedstock development from food crops through lignocellulosic residues to algae and waste streams; primary production pathways including microbial fermentation, ring-opening polymerization, and biosynthesis; forming processes from extrusion and injection molding to additive manufacturing; and the mechanical, thermal, and barrier properties that determine application fitness. Particular emphasis is placed on life cycle assessment, which reveals that bioplastics’ climate benefits are conditional on feedstock choice, land-use management, energy source at manufacturing, and end-of-life pathway, and that burden-shifting from greenhouse gas emissions to land use, water consumption, and eutrophication is a systematic risk requiring integrated LCA evaluation rather than single-metric optimization. The review further examines end-of-life recycling, composting, and biodegradation pathways; market applications across packaging, agriculture, automotive, biomedical, and electronics sectors; and the growing role of artificial intelligence and machine learning in accelerating materials design, process optimization, and lifecycle data management. Critical barriers to scale, such as cost premiums of 20–75% over conventional plastics, inadequate composting infrastructure, recycling stream contamination, regulatory fragmentation, and consumer labeling confusion, are systematically analyzed alongside mitigation strategies. The review concludes with a forward-looking discussion of emerging feedstocks, smart and functional bioplastics, and the policy and infrastructure investments required to translate the environmental promise of bio-based polymers into realized circular economy impact. Full article

Growing environmental concerns associated with Portland cement production, along with the continuous accumulation of construction and demolition waste, have intensified the need for sustainable construction materials and effective recycling strategies. This study experimentally investigates the performance of fly ash-based geopolymer concrete (GPC) incorporating recycled concrete aggregate (RCA) as a partial replacement for natural coarse aggregate, compared to conventional ordinary Portland cement concrete (OPC), with a particular focus on integrated durability performance. Ten mixtures were prepared, including five GPC and five OPC mixes with RCA replacement levels of 0–100% by volume. Mechanical properties were evaluated through compressive, splitting tensile, and flexural strength tests, while durability performance was assessed using water permeability, chloride penetration, acid resistance, elevated temperature exposure up to 1000 °C, and accelerated corrosion tests, supported by SEM–EDX analysis. Results show that GPC outperforms OPC across all replacement levels. Optimal performance was achieved at 20–40% RCA, while at 60% RCA a slight reduction in strength was observed; however, the values remained relatively high, particularly for GPC mixtures, indicating stable performance. A significant reduction occurred only at full replacement. GPC also exhibited lower permeability, enhanced corrosion resistance, improved thermal stability, and better resistance to acid attack. This study provides strong evidence that GPC can effectively compensate for the inherent limitations of RCA, offering a durable and eco-efficient alternative for structural and infrastructure applications. Full article

The smart city concept promotes the use of innovative solutions to improve residents’ quality of life while supporting sustainable urban development. In the context of climate change and rapid technological advancement, there is a growing demand for energy-efficient cooling systems that use natural resources. This study evaluates the influence of the hydrological regime of the Warta River on its cooling potential in Poznań, one of the largest cities in Poland. Based on hydrological data collected between 1971 and 2024, the distributions of river discharge and water temperature were analysed, as these represent the two key parameters determining the feasibility of river-based free-cooling systems. Considering environmental flow requirements and water temperature thresholds, several operating scenarios were developed to simulate cooling capacities of 100, 150, and 200 MW at temperature differences (ΔT) of 3 and 5 K. Among the analysed variants, the lowest cooling demand scenario (100 MW, ΔT = 3) provided suitable operating conditions for a river-based free-cooling system during 10,582 days, corresponding to 53.6% of the study period. In contrast, the highest cooling demand scenario (200 MW, ΔT = 5) was feasible during 43.9% of the analysed period. The results indicate that the Warta River has considerable potential as a natural cooling source for free-cooling applications, although this potential exhibits pronounced seasonal variability. The highest cooling capacity can be achieved during spring and autumn, while lower capacities are available in summer and the lowest in winter. River water temperature was identified as the dominant limiting factor, accounting for approximately 96% of all cases in which free-cooling operation was not feasible. Furthermore, the observed increase in river water temperature has reduced the number of summer days during which the required cooling capacity can be achieved. The findings enable the identification of periods when river water can fully or partially replace conventional mechanical cooling systems. They also provide a framework for assessing the seasonal and operational potential of surface waters in support of future investments integrating rivers into urban cooling infrastructure. Full article

The Middle Route of the South-to-North Water Diversion Project (SNWD-MR) serves as a strategic infrastructure critical to safeguarding water security in Northern China. Traversing complex geographical units, the project is perpetually exposed to long-term risks of land subsidence. Conventional Interferometric Synthetic Aperture Radar (InSAR) monitoring is hampered by waterbody isolation, causing spatial discontinuities in the retrieved deformation fields; furthermore, relying solely on deformation metrics fails to comprehensively quantify multidimensional risks. To address these issues, this study proposes an integrated assessment framework that couples time-series InSAR observations with the Analytic Hierarchy Process-Fuzzy Comprehensive Evaluation (AHP-FCE) model. To specifically mitigate the challenge of waterbody isolation, we developed a connectivity-aware multiscale down-sampling phase unwrapping strategy. By exploiting cross-canal bridges to construct a spatial connection network, a highly accurate, spatiotemporally continuous deformation field across the entire alignment was successfully reconstructed. Using the derived deformation field as the core dynamic indicator, an AHP-FCE model integrating hydrogeological features and human perturbations was constructed. A complementary evaluation process comprising sensitivity analysis and an internal physical consistency assessment was subsequently implemented. The results demonstrate that (1) the proposed algorithm effectively resolves the spatial discontinuity issue of the cross-canal deformation fields, reducing the deformation-velocity RMSE from 7.9 to 5.7 mm/y, corresponding to an approximately 27.8% reduction in RMSE relative to the traditional Minimum Cost Flow (MCF) method; (2) land subsidence along the alignment exhibits prominent spatial heterogeneity, with the northern Henan and southern Hebei sections identified as very-high-risk zones; and (3) InSAR deformation magnitude and the groundwater elevation indicator emerge as the most influential factors in the modeled risk distribution. Overall, this study expands conventional deformation monitoring into a systematic, quantitative risk assessment framework, thereby providing scientific insights and theoretical support for the early warning of geo-hazards and the smart operation and maintenance of large-scale water diversion projects. Full article

Sustainable and reliable operation of water distribution systems requires timely detection of bursts and effective control of real water losses. The digitalisation of water utilities and the increasing deployment of smart monitoring infrastructures are enabling continuous monitoring and diagnostic support, but the development of operational anomaly detection tools remains constrained by scarce labelled events and by the lack of structured workflows for designing, testing and comparing alternative solutions. This study proposes a methodology for developing and benchmarking burst detection tools in water distribution systems. The framework integrates stochastic-hydraulic synthetic data generation to create or enrich labelled datasets, feature engineering to extract temporal and spatial descriptors from hydraulic signals, baseline modelling of normal system behaviour, residual generation, anomaly identification, and systematic performance evaluation. The methodology is applied to a real water distribution network partitioned into nine district metered areas, enabling a consistent comparison of alternative strategies for normal-behaviour modelling and anomaly detection. Results show that the forecasting-based approach, including multi-horizon prediction, produces more informative residuals than the reconstruction-based approach, while XGBoost provides the best overall trade-off between sensitivity and false alarms. These findings demonstrate the value of the proposed methodology for the data-driven development of operational burst detection tools in smart water distribution systems. Full article