Search Results (207)

Protection of coastal cultural heritage is among the most urgent global priorities, as these sites face increasing threats from climate change, sea level rise, and human activity. This study emphasises the value of innovative geospatial tools and data ecosystems for timely risk assessment. The role of land administration systems, geospatial documentation of coastal cultural heritage sites, and the adoption of innovative techniques that combine various methodologies is crucial for timely action. The coastal management infrastructure in Greece is presented, outlining the key public authorities and national legislation, as well as the land administration and geospatial ecosystems and the various available geospatial ecosystems. We profile the Hellenic Cadastre and the Hellenic Archaeological Cadastre along with open geospatial resources, and introduce TRIQUETRA Decision Support System (DSS), produced through the EU’s Horizon project, and a Digital Twin methodology for hazard identification, quantification, and mitigation. Particular emphasis is given to the role of Digital Twin technology, which acts as a continuously updated virtual replica of coastal cultural heritage sites, integrating heterogeneous geospatial datasets such as cadastral information, photogrammetric 3D models, climate projections, and hazard simulations, allowing for stakeholders to test future scenarios of sea level rise, flooding, and erosion, offering an advanced tool for resilience planning. The approach is validated at the coastal archaeological site of Aegina Kolona, where a UAV-based SfM-MVS survey produced using high-resolution photogrammetric outputs, including a dense point cloud exceeding 60 million points, a 5 cm resolution Digital Surface Model, high-resolution orthomosaics with a ground sampling distance of 1 cm and 2.5 cm, and a textured 3D model using more than 6000 nadir and oblique images. These products provided a geospatial infrastructure for flood risk assessment under extreme rainfall events, following a multi-scale hydrologic–hydraulic modelling framework. Island-scale simulations using a 5 m Digital Elevation Model (DEM) were coupled with site-scale modelling based on the high-resolution UAV-derived DEM, allowing for the nested evaluation of water flow, inundation extents, and velocity patterns. This approach revealed spatially variable flood impacts on individual structures, highlighted the sensitivity of the results to watershed delineation and model resolution, and identified critical intervention windows for temporary protection measures. We conclude that integrating land administration systems, open geospatial data, and Digital Twin technology provides a practical pathway to proactive and efficient management, increasing resilience for coastal heritage against climate change threats. Full article

Agricultural trade not only facilitates the exchange of final products but also leads to the indirect transfer of arable land resources involved in their production processes across countries. These indirect flows are commonly referred to in the literature as virtual land flows or virtual land trade. An in-depth understanding of the factors influencing virtual land flows is crucial for both the management of these flows and the sustainable and efficient allocation of limited arable land resources on a global scale. The objective of this study is to identify the key determinants that influence virtual land flows in Türkiye’s trade of plant-based agricultural products. To achieve this, the virtual land trade balance for Türkiye was computed by estimating the import and export volumes of virtual land from 1986 to 2019, based on crop, year, and country-specific yield values. Subsequently, the relationship between Türkiye’s virtual land trade balance and macroeconomic and environmental variables—such as Gross Domestic Product (GDP), the real effective exchange rate, annual total precipitation, per capita arable land, and fertilizer usage—was investigated using the ARDL bounds testing approach. The findings of this study indicate that the most significant factors influencing Türkiye’s virtual land flows are per capita arable land endowment and fertilizer usage. This result highlights the strong relationship between virtual land flows and variables related to productivity and natural resource endowment, while also emphasizing the importance of integrating sustainability considerations and environmental impacts into contemporary agricultural policy frameworks. Elucidating the dynamics of virtual land trade is a pivotal step toward ensuring the long-term sustainability of international agricultural trade, as well as the equitable and efficient allocation of arable land resources. Furthermore, it represents a fundamental strategy for global agricultural production, offering critical insights for shaping future agricultural policy and practice at the global level. Full article

With industrial transformation and the rise in the 15 min community life circle, optimizing walkability and preserving industrial heritage are key to revitalizing former industrial areas. This study, focusing on Shijingshan District in Beijing, proposes a walkability evaluation framework integrating multi-source big data and street-level perception. Using Points of Interest (POI) classification, which refers to the categorization of key urban amenities, pedestrian network modeling, and street view image data, a Walkability Friendliness Index is developed across four dimensions: accessibility, convenience, diversity, and safety. POI data provide insights into the spatial distribution of essential services, while pedestrian network data, derived from OpenStreetMap, model the walkable road network. Street view image data, processed through semantic segmentation, are used to assess the quality and safety of pedestrian pathways. Results indicate that core communities exhibit higher Walkability Friendliness Index scores due to better connectivity and land use diversity, while older and newly developed areas face challenges such as street discontinuity and service gaps. Accordingly, targeted optimization strategies are proposed: enhancing accessibility by repairing fragmented alleys and improving network connectivity; promoting functional diversity through infill commercial and service facilities; upgrading lighting, greenery, and barrier-free infrastructure to ensure safety; and delineating priority zones and balanced enhancement zones for differentiated improvement. This study presents a replicable technical framework encompassing data acquisition, model evaluation, and strategy development for enhancing walkability, providing valuable insights for the revitalization of industrial districts worldwide. Future research will incorporate virtual reality and subjective user feedback to further enhance the adaptability of the model to dynamic spatiotemporal changes. Full article

The Songnen Grassland, a typical saline–alkali ecosystem in Northeast China, is increasingly degraded by soil salinization. Arbuscular mycorrhizal fungi (AMF) are critical for enhancing plant tolerance to saline–alkali stress via root symbiosis. To investigate the species diversity and community structure of AMF in the rhizosphere of salt-tolerant plants in the Songnen Grassland, this study combined morphological identification with high-throughput sequencing (based on virtual taxa, VTs, from the MaarjAM database) to analyze the composition and distribution characteristics of AMF in the rhizosphere of eight salt-tolerant plant species, including Arundinella anomala, Leymus chinensis, Taraxacum mongolicum and others. Morphological identification revealed a total of 22 AMF species belonging to 7 genera. Among these, the genus Glomus was the dominant genus, comprising eight species (accounting for 36.4% of the total species), followed by the genus Acaulospora (five species, 22.7%), the genus Rhizophagus (four species, 18.2%), the genus Ambispora (two species, 9.1%), and the remaining genera each represented by one species (4.5%). High-throughput sequencing analysis identified a total of 40 virtual taxa (VTs) with clear taxonomic assignments belonging to six genera. The genus Glomus accounted for the highest proportion (34 VTs, 85%) with a relative abundance of 89.33%, representing the overwhelmingly dominant group. Rhizosphere soil electrical conductivity (EC) of the eight plant species indicated a significant gradient (high EC group: A–D and G, 2.07–2.61 mS/cm; low EC group: E, F, H, 0.20–0.48 mS/cm). The AMF diversity in the high EC group was significantly higher than that in the low EC group, indicating that AMF in the rhizosphere of salt-tolerant plants enhanced plant tolerance to high-salt environments, and their diversity did not decrease with increasing salinity but instead remained at a high level. Plant-specific AMF community characteristics were evident. Hierarchical clustering analysis further confirmed that the AMF community composition in the rhizosphere of Taraxacum mongolicum and Vicia amoena differed significantly from that of the other plant species, indicating that plant species have a key driving role in AMF community structure. These findings provide critical insights into the plant–AMF symbiotic mechanisms underlying saline–alkali adaptation and offer a theoretical basis for selecting efficient AMF strains to support ecological restoration of saline–alkali lands. Full article

This research aims to characterize sediment dynamics in the Rupinaro catchment, a uniquely terraced and human-shaped basin in Italy’s Liguria region, employing geomorphometric methods to unravel sediment connectivity in a landscape vulnerable to shallow landslides. Within a scenario-based approach, we utilized high-resolution LiDAR-derived digital terrain models (DTMs) to calculate the Connectivity Index, comparing sediment dynamics between the original terraced landscape and a virtual natural scenario. To reconstruct a pristine slope morphology, we applied a topographic roughness-based skeletonization algorithm that simplifies terraces into linear features to simulate natural hillslope conditions and remove anthropogenic structures. The analysis was carried out considering diverse targets (e.g., hydrographic networks, road networks) and the effect of land use. The results reveal significant differences in sediment connectivity between the anthropogenic and natural morphologies, with implications for erosion and landslide susceptibility. The findings reveal that sediment connectivity is moderately higher in the scenario without terraces, indicating that terraces function as effective barriers to sediment transfer. This highlights their potential role in mitigating landslide susceptibility on steep slopes. Additionally, the results show that roads exert a stronger influence on the Connectivity Index, significantly altering flow paths. These modifications appear to contribute to increased landslide susceptibility in adjacent areas, as reflected by the higher observed landslide density within the study region. Full article

As urban populations expand and congestion intensifies, traditional ground transportation struggles to satisfy escalating mobility demands. Unmanned Electric Vertical Take-Off and Landing (eVTOL) aircraft, as a key enabler of Urban Air Mobility (UAM), leverage low-altitude airspace to alleviate ground traffic while offering environmentally sustainable solutions. However, supporting high bandwidth, real-time video applications, such as Virtual Reality (VR), Augmented Reality (AR), and 360° streaming, remains a major challenge, particularly within bandwidth-constrained metropolitan regions. This study proposes a novel Unmanned Aerial Vehicle (UAV)-enabled video streaming architecture that integrates 6G wireless technologies with intelligent routing strategies across cooperative airborne nodes, including unmanned eVTOLs and High-Altitude Platform Systems (HAPS). By relaying video data from low-congestion ground base stations to high-demand urban zones via autonomous aerial relays, the proposed system enhances spectrum utilization and improves streaming stability. Simulation results validate the framework’s capability to support immersive media applications in next-generation autonomous air mobility systems, aligning with the vision of scalable, resilient 3D transportation infrastructure. Full article

Virtual reality (VR) technology is becoming increasingly relevant as a modern educational tool. However, its application in teaching and learning computational thinking remains relatively underexplored. This paper presents the implementation of selected tasks from the international Bebras Challenge in a VR environment called ThinkLand. A comparative study was conducted to evaluate the usability of the developed game across two interface types: mobile devices and desktop computers. A total of 100 participants, including high school and university students, took part in the study. The overall usability rating was classified as “good”, suggesting that ThinkLand holds promise as a platform for supporting computational thinking education. To assess specific aspects of interface usability, a custom Virtual Environment Usability Questionnaire (VEUQ) was developed. Regression analysis was performed to examine the relationship between participants’ age, gender, and interface type with both learning performance and perceived usability, as measured by the VEUQ. The analysis revealed statistically significant differences in interaction patterns between device types, providing practical insights for improving interface design. Validated in this study, the VEUQ proved to be an effective instrument for informing interaction design and guiding the development of educational VR applications for both mobile and desktop platforms. Full article

(1) Background: Cultural heritage plays a vital role in shaping collective identity and supporting tourism, yet it faces increasing threats from natural and human-induced disasters. As a response, digital technologies—especially drone-based monitoring systems—are being explored for disaster prevention. This study examines whether a Genetic Algorithm can effectively optimize the placement of drone stations for the economic protection of cultural heritage. (2) Method: A simulation was conducted in a 2500 km² virtual space divided into 25 km² grid units, each assigned a random land price. Drone stations have an operational radius of 40 km. GA optimization uses a fitness function based on the ratio of cultural artifacts covered to installation cost. To prevent premature convergence, multi-point crossover and roulette wheel selection are employed. Key GA parameters were fine-tuned through repeated simulations. (3) Results: The optimal parameter set—population size of 300, mutation rate of 0.2, mutation strength of ±5 km, and crossover ratio of 0.3—balances exploration and convergence. The results show convergence toward low-cost, high-coverage locations without premature stagnation. Visualization clearly illustrates the optimization process. (4) Conclusions: GA proves effective for economically optimizing drone station placement. Though virtual, this method offers practical implications for real-world cultural heritage protection strategies. Full article

Water plays a critical role in ensuring sustainable food security, particularly in the face of increasing freshwater scarcity and climate variability. This study examines virtual water use and virtual water trade in Ghana’s vegetable production sector over a 30-year period (1994–2023), focusing on four key crops: tomato, pepper, onion, and eggplant. Using secondary data on production volumes, trade flows, and virtual water content, the research quantifies imported and exported virtual water volumes and assesses net virtual water trends. The results reveal a substantial increase in virtual water use for most crops, with the exception of pepper, which experienced a marked decline. Onion and tomato are identified as the dominant contributors to both imports and exports of virtual water, while pepper and eggplant play relatively minor roles. The study finds that Ghana is a net importer of virtual water in vegetable trade, emphasizing the need for integrated water resource management to balance agricultural growth with water sustainability. A gravity model analysis was applied to identify the primary determinants of virtual water trade, revealing that GDP per capita, population size, distance, land availability, virtual water use, and border-sharing significantly influence trade patterns. The findings suggest that enhancing domestic production capacity and promoting efficient water use practices can reduce Ghana’s reliance on imports and improve resilience against water-related risks. This research provides valuable insights for policymakers, researchers, and practitioners aiming to develop sustainable water and food systems in Ghana and similar contexts. Full article

Investigating the coupling coordination between urban scale and vitality is critical for enhancing holistic urban development quality and advancing sustainability. Taking the Changsha-Zhuzhou-Xiangtan (ChangZhuTtan) metropolitan area as a case study, this research integrates multi-source raster and vector data to: (1) analyze spatial patterns of urban scale and virtual–substantive vitality; (2) delineate a “scale-vitality” hierarchical zonal structure; (3) quantify coupling relationships across subzones; and (4) propose synergistic spatial optimization strategies. Key findings reveal that, distinct core-periphery structure characterizes urban scale and vitality, with Changsha’s central districts dominating population, land use, and economic metrics, while Zhuzhou and Xiangtan exhibit moderate concentrations. Significant positive correlations exist between urban scale and dual vitality types, with scale-driven vitality enhancement being most pronounced in core agglomeration zones. Furthermore, in the metropolitan core, where both urban scale and vitality values are high, they exhibit a high-value coupling state. As they expanded outward, both metrics gradually decreased, resulting in a low-value coupling state. However, zonal comparisons (core agglomeration circle–peripheral expansion circle) reveal that the proportion of spatially coupled units progressively increases. By elucidating scale-vitality coupling in the ChangZhuTtan metropolitan area, this study provides actionable insights for spatial planning and sustainable urban transition. The methodology framework is replicable for similar metropolitan regions globally. Full article

This study aims to design a novel combined spherical tensegrity structure and evaluate its cushioning performance to offer a new option for a planetary exploration landing mechanism. Initially, based on the circumferential assembling method, a “class II” spherical tensegrity structure was constructed using the square frustum tensegrity unit as the basic element. Then, the equilibrium equations for the structure were formulated in accordance with the principle of virtual work to confirm the self-equilibrium of the tensegrity configuration, and the stability of the designed structure was assessed by determining the type of the tensegrity structure according to the Maxwell criterion and the character of the stiffness matrix. Subsequently, the simulation and analysis of the compressive stiffness of the structure under different parameters were carried out based on the finite element analysis method. The landing collision was simulated by using dynamic software to analyze the influence of the structure parameters on the cushioning performance. Finally, an experimental model was built to verify the above analysis, which demonstrates that the designed spherical tensegrity structure offered a large loading space and great cushioning performance. Full article

Influential studies in the history of cartography have argued that map-like representations of space were (virtually) unknown in the Classical Mediterranean world and that the cause of this was an absence of underlying cognitive maps. That is, persons in that time/place purportedly had only route/egocentric-type mental representations, not survey/allocentric ones. The present study challenges that cognitive claim by examining the verbal descriptions of plots of land produced by ancient Roman land-measurers. Despite the prescription of a route-based form, actual representations persistently show a variety of features which suggest the existence of underlying survey-type mental models and the integration of those with the route-type ones. This fits better with current views on interaction between types of spatial representation and of cultural difference in this area. The evidence also suggests a linkage between the two kinds of representations. Full article

Improvements in immersive technology are opening up new opportunities for land management and urban planning, enabling the creation of detailed virtual models for examining and simulating real-world short-, medium-, and long-term scenarios. The goal of this research is to present the creation of an urban digital twin based on a virtual reality city replica, that models and visualizes the urban environment in three dimensions using advanced geomatics techniques and IoT technologies. The methodology focuses on two case studies that utilize environmental analysis and virtual simulation: assessing hydrogeological risk and evaluating public light pollution. The Cesium platform was employed to build high-precision 3D models based on topographic, meteorological, and infrastructure data. The proposed methodology calculated a correlation between light pollution and CO₂ equal to 0.51 and a correlation between precipitation, slope, and risk area higher than 0.80. The most critical and high-risk classes are as follows: Dense Discontinuous Urban Fabric, Roads and Associated Lands, Pastures, and Forests. Results show how an urban digital twin can be a powerful tool for monitoring and territorial planning, with concrete applications in the public and risk management fields. This study also highlights the importance of geomatics technologies in the creation of realistic and functional virtual environments for the assessment and sustainable management of urban resources. Full article

In order to enhance the precision of UAV (unmanned aerial vehicle) landings and realize the convenient and rapid deployment of the model to the mobile terminal, this study proposes a Land-YOLO lightweight UAV-guided landing algorithm based on the YOLOv8 n model. Firstly, GhostConv replaces standard convolutions in the backbone network, leveraging existing feature maps to create additional “ghost” feature maps via low-cost linear transformations, thereby lightening the network structure. Additionally, the CSP structure of the neck network is enhanced by incorporating the PartialConv structure. This integration allows for the transmission of certain channel characteristics through identity mapping, effectively reducing both the number of parameters and the computational load of the model. Finally, the bidirectional feature pyramid network (BiFPN) module is introduced, and the accuracy and average accuracy of the model recognition landing mark are improved through the bidirectional feature fusion and weighted fusion mechanism. The experimental results show that for the landing-sign data sets collected in real and virtual environments, the Land-YOLO algorithm in this paper is 1.4% higher in precision and 0.91% higher in mAP0.5 than the original YOLOv8n baseline, which can meet the detection requirements of landing signs. The model’s memory usage and floating-point operations per second (FLOPs) have been reduced by 42.8% and 32.4%, respectively. This makes it more suitable for deployment on the mobile terminal of a UAV. Full article

Virtual Reality (VR) has emerged as an effective technology for the dissemination of geographical knowledge due to its visual, interactive, and dynamic nature. This technology allows for adequate valorization of the territorial attributes of marginal mountain areas undergoing tertiarization processes, as it provides suggestive experiences of approach, discovery, and interpretation. All of this should result in the fortification of the conservation process against the expansion of new uses that impact the inherited landscape. In this work, the aim was to design a VR experience for the interpretation of mountains that can be used by public and private entities as a strategy for differentiation in the context of positioning for territorial development. The study area covers the mountain pass of Leitariegos and the Cueto Arbás massif (a mountain in the west of Asturias and León, Northwestern Spain), which make up a geographical unit with ecological, aesthetic, ethnographic, and historical importance. Using a VR tool, we sought to enhance the identification and interpretation of the keys that lead to the initiation and consolidation of the patrimonialization process, uncovering the processes and agents through their practices, the vectors around which the process pivots, and the conflicts in the competition for land use. Full article