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Underwater optical imaging is essential for exploring the underwater environment to provide information for planning and regulating underwater activities in various underwater applications, such as aquaculture farm observation, underwater topographical survey, and underwater infrastructure monitoring. Thus, there is a need to investigate the underwater imaging process and propose clear and long-range underwater optical imaging methods to fulfill the demands of academia and industry. In this manuscript, we classify the eighteen most commonly used underwater optical imaging methods into two groups regarding the imaging principle, (1) hardware and (2) software-based methods, each with an explanation of the theory, features, and applications. Furthermore, we also discuss the current challenges and future directions for improving the performance of current methods, such as improving the accuracy of underwater image formation model estimation, enlarging the underwater image dataset, proposing comprehensive underwater imaging evaluation metrics, estimating underwater depth and integrating different methods (e.g., hardware- and software-based methods for computational imaging) to promote the imaging performance not only in the laboratory but also in practical underwater scenarios. [ABSTRACT FROM AUTHOR]

The Real-Time Kinematic (RTK) method is currently the most widely used method for positioning using Global Navigation Satellite Systems (GNSSs) due to its accuracy, efficiency and ease of use. In forestry, position is a critical factor for numerous applications, with GNSS currently being the preferred solution for obtaining such data. However, the decreased performance of GNSS observations in challenging environments, such as under the forest canopy, must be considered. This paper analyzes the performance of a survey-grade GNSS receiver under coniferous/deciduous tree cover. Unlike most previous research concerning this topic, the focus here is on employing a methodology that is as close as possible to real working conditions in the field of forestry. To achieve this, short observation times of 30 s were used, with corrections received directly in the field from a Continuously Operating Reference Station (CORS) of the national RTK network in Romania. In total, 84 test points were determined, randomly distributed under the canopy, with reference data collected by topographical surveys using total station equipment. In terms of the overall horizontal accuracy, an RMSE of 2.03 m and MAE of 1.63 m are found. Meanwhile, the overall vertical accuracy is lower, as expected, with an RMSE of 4.85 m and MAE of 4.01 m. The variation in GNSS performance under the different forest compositions was found to be statistically significant, while GNSS-specific factors such as DOP values only influenced the precision and not the accuracy of observations. We established that this methodology offers sufficient accuracy, which is application-dependent, even if the majority of GNSS solutions were code-based, rather than carrier-phase-based, due to strong interference from the vegetation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Anatolian Environmental & Animal Science is the property of Bulent Verep and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The impacts of climate change manifest heterogeneously across regions, and in Khovd City, a semi-arid area in Western Mongolia, the escalating threat of flooding is evident through the occurrence of 10 flash floods in the last 30 years. The risk zone, encompassing rivers and flash floods, endangers ca. 32,000 residents, with 750–1,800 traditional nomadic dwellings (ger s) located on the floodplain of the Buyant River during summer. There is a risk of flash floods in the eastern part of Khovd City from the mountains, while the western part is at a higher risk of flooding from the Buyant River. This paper aims at assessing flood hazards through a detailed topographical survey conducted using an Unmanned Aerial Vehicle (UAV). 15,206 aerial photos were collected in Khovd City using the UAV and measured by Real-Time Kinematic (RTK) on 22 Ground Control Points (GCPs). A Digital Elevation Model (DEM) with a resolution of 2.7 meters was generated from the aerial drone mapping data, enabling surface morphology, hydrological and eight-direction pour point model analysis using a Geographic Information System (GIS). The resulting flood hazard map revealed 4 flood risk areas based on flood flow direction and topographical features. Recommendations for local govern and residents include enhancing flood protection facilities for flood disaster prevention on flood risk zones. [ABSTRACT FROM AUTHOR]

Remote sensing plays a crucial role in detecting and monitoring natural resources, extending its applications to various fields, such as geography, topographical surveying, and geoscience disciplines, including land management, forest monitoring, crop identification, soil mapping, and ocean resource finding. Road extraction holds significant importance among these applications, contributing to the development of Geographic Information Systems (GIS). The automatic updating of GIS information has become essential in daily life. Road extraction stands out as a prominent application within remote sensing image systems, addressing challenges related to intensity and width. Intensity challenges involve variations in spectral or color values of roads, while width challenges pertain to the issues associated with the size and structure of roads during the extraction process. Addressing the challenges associated with road extraction from remote sensing imagery is crucial for achieving accurate and efficient results. This paper under consideration compares the conventional and contemporary methods of road extraction, emphasizing completeness and correctness metrics. Conventional methods involve techniques like CLAHistogramEqualization for enhancement and fuzzy c-mean clustering for extraction, resulting in incremental improvements. To enhance results further, images are de-noised using Gray World Optimization and iterative domain-guided image filtering. To improve efficiency in road extraction, the authors proposed a contemporary approach through probability neural networks with de-noised images. The comparison is made based on the completeness and correctness of both conventional and contemporary methods. [ABSTRACT FROM AUTHOR]

To better understand the location and help in the conservation of buried structures in the ancient site of Tusculum, in Central Italy, archaeological and multi-methodological geophysical studies were developed in the recent last years. These studies included geophysical surveys, which were combined with topographical survey and direct archaeological excavations. Tusculum is one of the largest Roman archaeological sites in the Alban Hills, located in the Latium region (Italy), about 25 km South-East of Rome. This settlement was inhabited since pre-Roman times, up to the middle ages. The objective of the Tusculum Project is to verify the town-planning of Tusculum and to obtain information about the location, shape, depth and size of the hypothesised buried buildings. With these aims, multi-methodological geophysical surveys have been carried out in the time range 2016–2019 to locate the archaeological remains in different portions of the studied area and to verify the orientation of the underground aqueduct system. GPR and gradiometric surveys were carried out to investigate the archaeological remains, while ERT surveys, were employed to find evidence of undiscovered parts of the underground aqueduct system. These results, along with geological studies and historic evidence, are being examined by archaeologist to understand the limits of the town and how water was supplied to such a large, populated settlement. The obtained results show very good correspondence between the buried architecture, the geophysical anomalies and the archaeological excavations. A number of unexpected buried buildings were discovered, which were excavated in 2017 and 2018, which showed remains of buried public thermal bath and a large church with surrounding funerary area built in the Middle Ages. [ABSTRACT FROM AUTHOR]

Bowen's disease is a cutaneous squamous cell carcinoma in situ, a rare precancerous disease most frequently manifested by an erythematous, scaly crusted plaque on sun-exposed areas. We report on the case of an 83-year-old female, with an asymptomatic, erythematous scaly plaque, within an uncommon topographic setting, a peculiar localization that prompted a series of inquiries into multiple potential differential diagnoses. We also review the main treatment options, among which surgical extension, cryotherapy, topical agents, or photodynamic therapy are of paramount importance. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present the results of the research undertaken through a series of on-site surveys (2021-2023) at the Sasso Pinzuto site, located approximately 1 km SE of Tuscania (Viterbo, Italy). Situated along the eastern side of the Marta river valley, the necropolis layout is little known but it is extensive, including ca. 100 rock-cut chamber tombs. The 2021-22 archaeological campaigns started with a new topographical survey of the site and investigated two areas conventionally defined the Northern and the Southern Area. In the Northern Area, specifically within the vicinity of Tumulus 1, fragments of mould-decorated architectural plaques from a building discovered. In the Southern Area, a small plateau about 90 m from the Northern Area, four burial graves (n. 126, 127, 128, 130) and two chamber tombs (125 and 129) were excavated. This study sheds light to the great potential of applying digital technologies for a new understanding of the Etruscan tombs. Indeed, by using various non-destructive prospecting methods (aerial photogrammetry, fieldwalking survey, architectural drawings), coupled with precise location using RTK GNSS, and integration of legacy data in GIS, the site underwent a comprehensive reexamination. [ABSTRACT FROM AUTHOR]

Mediterranean cyclones (MCs) govern extreme weather events across the Euro-African Basin, affecting the lives of hundreds of millions. Despite many studies addressing MCs in the last few decades, their correct simulation and prediction remain a significant challenge to the present day, which may be attributed to the large variability among MCs. Past classifications of MCs are primarily based on geographical and/or seasonal separations; however, here we focus on cyclone genesis and deepening mechanisms. A variety of processes combine to govern MC genesis and evolution, including adiabatic and diabatic processes, topographic influences, land–sea contrasts, and local temperature anomalies. As each process bears a distinct signature on the potential vorticity (PV) field, a PV approach is used to distinguish among different "types" of MCs. Here, a combined cyclone-tracking algorithm is used to detect 3190 Mediterranean cyclone tracks in ECMWF ERA5 from 1979–2020. Cyclone-centered, upper-level isentropic PV structures in the peak time of each cyclone track are classified using a self-organizing map (SOM). The SOM analysis reveals nine classes of Mediterranean cyclones, with distinct Rossby-wave-breaking patterns, discernible in corresponding PV structures. Although classified by upper-level PV structures, each class shows different contributions of lower-tropospheric PV and flow structures down to the surface. Unique cyclone life cycle characteristics, associated hazards (precipitation, winds, and temperature anomalies), and long-term trends, as well as synoptic, thermal, dynamical, seasonal, and geographical features of each cyclone class, indicate dominant processes in their evolution. Among others, the classification reveals the importance of topographically induced Rossby wave breaking to the generation of the most extreme Mediterranean cyclones. These results enhance our understanding of MC predictability by linking the large-scale Rossby wave formations and life cycles to coherent classes of under-predicted cyclone aspects. [ABSTRACT FROM AUTHOR]

In this paper, a topographical survey was carried out and the resulting data were processed for the development of the Zănoaga area in Bran, as a multifunctional sports complex. For the existing ski slope, all field data were collected, and a corresponding database was constructed. For the rest of the area, a comprehensive survey was conducted to establish the routes for a summer toboggan run, a tubing installation, and a bike trail (with multiple variants). A ComNav T300 GNSS equipment was used. Field data were initially processed in AutoCAD Civil 3D and then imported into ArcGIS. In this latter program, the initial 3D profile, and the possible profiles for optimal operation of the mentioned facilities were created. A program model was built in GIS through which the user can choose the suitable slope according to their experience, and the construction mode of the summer slope was simulated, based on projected speed. [ABSTRACT FROM AUTHOR]

Recent technological interventions in healthcare, such as robots or artificial intelligence are often described as being made with algorithms and data points, in contrast to human care, which is couched in terms of intimacy and fleshy encounters, exemplified in the sensory act of touch. In this article I problematize such distinctions by looking at how training the sensory skills of diagnosis also involves technologies with data points, specifically grids. Drawing from ethnographic fieldwork in what is known as a "skills laboratory" in the Netherlands, I focus on how students learn how to perform an abdominal examination, a tactile practice learnt via a grid. Bringing ethnographic material into dialogue with accounts of grids in art history, history of science and computer science, I suggest that gridding is an important, multisensory and multimodal practice of boundary-making in medicine, but that moreover it helps build clinical perception. In doing so, just as in the making of robots and smart machines, these grids enact their own biopolitical assumptions. This article develops an empirical and theoretical understanding of how technologies and flesh become affectively entangled in the very earliest of clinical encounters. [ABSTRACT FROM AUTHOR]

The Messapian necropolis of Monte D'Elia (used from the 6th to the 2nd cent. BC) is about 300 m S of the modern town of Alezio (Lecce, Apulia), which lays on one of the most important ancient settlements of the Salento peninsula (ancient Messapia). The site was investigated between 1981 and 1985 by the Apulian Archaeological Superintendence. In 2020, archaeological investigations have been resumed by the Department of Cultural Heritage of the University of Salento, with the participation of researchers from the Institute of Heritage Science of the National Research Council. Their research activities focused on geophysical prospecting and topographical surveys, performed thanks to the combined use of laser scanner and digital photogrammetry by drone. This contribution illustrates these research activities, which are aimed at understanding the general plan of the necropolis, through the integration of the information published in the 1980s with data from new investigations and surveys, and, more generally, at the reconstruction of its topographic organization and extension. [ABSTRACT FROM AUTHOR]

Copyright of Prague Egyptological Studies / Prazské Egyptologické Studie is the property of Charles University Prague, Faculty of Arts and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil excavation represents a fundamental step in the construction and development of infrastructure. Despite the widespread application of best practices and regulations, accidents in the construction industry are comparatively higher than those in other industries. Deep excavations have the potential to cause adverse effects on the stability of the soil and nearby structures. Thus, in addition to ensuring safety, it is necessary to assess and monitor the environmental impact of deep excavations during construction processes. An eloquent example is represented by monitoring the marble resources exploitation from the quarry located in the "Dealul Maria" perimeter, in the town of Ruschia, through topographical surveys realized with a view to determine volumes, carried out quarterly, for a period of 5 years. The achieved 3D modeling highlights the differences between the initial shape of the natural land before the start of exploitation, the resulting shape of the land at different stages of the exploitation and the final shape as well as supports a proposal to green the exploited area by restoring the exploited land to a form as close as possible to the original one. [ABSTRACT FROM AUTHOR]

New technologies such as the I-BIM (Infrastructure Building Information Modeling) are radically changing the infrastructure design and construction sector. In this study, the I-BIM approach has been used for the design of a portion of the future Bologna's Red Tramway Line. Starting from the topographical survey of the area, a "federated" model was created, aggregating in a single digital environment all the models inherent to the individual disciplines involved. Interference analysis (Clash Detection) between the various disciplines was performed, subject to the preparation of a coordination matrix and the temporal simulation of the worksite phases (BIM 4D). The results have shown that the I-BIM approach represents a powerful tool for optimizing and validating infrastructure design, allowing users to see how the infrastructure integrates and fits into the real 3D environmental context. [ABSTRACT FROM AUTHOR]

Cadastral marks constitute a dense source of information for topographical surveys required to update cadastral maps. Historically, in Italy, cadastral marks have been the cartographic network for the implementation of mapping updates. Different sources of cadastral marks can be used by cadastral surveyors. In recent years, the cadastre is moving toward a digital world, and with the advancement of surveying technology, GNSS CORS technology has emerged in the positioning of cadastral marks. An analysis of congruence among cadastral marks using GNSS CORS and official maps is missing. Thus, this work aims to analyze the positional accuracy of some cadastral marks, located in Palermo, Italy, with regard to the official maps produced by the cadastral bureau, the local cartography, and Google Earth maps. A survey of 60 cadastral marks was carried out by conventional GNSS NRTK procedures, with the lateral offset method due to their materialization (mostly building edges), which is not always directly detectable. The cadastral marks' positioning was obtained from different maps: cadastral maps and related monographic files, numerical technical maps, and Google Earth maps, to check their coordinate congruence. A statistical approach was performed to check whether the distribution frequencies of the coordinate's differences belonged to the bivariate normal distribution for the planimetric coordinates and the univariate normal distribution for the altimetric component. The results show that the hypothesis of a normal distribution is confirmed in most of the pairs, and specifically, most of the analyses indicate that the highest congruencies seem to characterize the coordinates determined by using the GNSS and with those that can be deduced by the numerical technical maps. The results obtained experimentally show centimetric accuracies obtained by the GNSS NRTK survey, in both the planimetric and altimetric components, while the accuracies obtained from the georeferencing of the cadastral maps show differences in the order of 0.4–0.8 m. Meanwhile, the differences resulting from comparing the technical cartography produced by the local authority and Google Earth maps show greater criticalities, with a metric order of magnitude. [ABSTRACT FROM AUTHOR]

With the advancement of sensor technology, unmanned aerial vehicles (UAVs) or drones revolutionize several fields including topographic surveying, agriculture, recreation, emergency, rescue and so on. The autonomous flight modes available in current UAVs make it broaden to manoeuvring by an unskilled person. This, of course, causes to widely use the drone technology among different user communities. Of the revolutionized fields, topographic surveying is prominent because many low cost UAVs with on-board light weight optical payloads often deliver mapping products such as ortho-photos and DEMs with centimetre level accuracy (in XY and Z) that had been exclusively bounded to the expensive field surveying methods earlier. Though drones enables to obtain centimetre level geometric accuracy, the main drawback of the technology is inability to see underneath vegetation canopy which hinders applicability of drones for a complete topographical survey. In order to view beneath the tree canopies, UAV LiDAR is a solution but due to its high cost, it is still not popular among several communities who involve with land surveying. To measure underside vegetation, field surveying methods such as total stations and theodolites traversing are being mainly practised by the users. But it is also not a viable solution since it consumes much time and money. If remotely sensed data collection is able to capture landscapes that had been hampers by the canopies, definitely it will be a cost effective and a rapid solution. As such, oblique imagery (UAV) acquired in manual flight mode at very low altitudes is a good solution. The objective of the study is to develop a novel approach to generate UAV deliveries without vegetation canopy in vegetated areas.First, autonomous flight mission is completed while maintaining 80% and 70% forward and lateral overlaps. For the terrain patches where they are covered by tree canopies, oblique imageries have been collected while operating the drone manually at low altitudes. Each UAV flight is separately processed and merged in to a single image to extract 2D maps without gaps beneath tree canopies. Re-sampling is fulfilled prior to stitching in order to gain a seamless product. Performed accuracy analysis confirmed that the developed approach is sufficient to produce DTMs and ortho-mosaics having average RMSE-XY 0.087m and RMSE-Z 0.177m at 4.0cm GSD which is really acceptable. Besides, there is not any significant accuracy variation between underneath canopy areas and open areas. [ABSTRACT FROM AUTHOR]

In recent years, many landslides have occurred in Vietnam, particularly in the Northern mountainous region during the rainy season from May to October. On the morning of October 12, 2017, the Khanh waterfall landslide in Khanh Village, Hoa Binh Province, Northern Vietnam occurred. The landslide killed eighteen people and destroyed five houses. Topographical and geological surveys were conducted around the area to determine its causes. The rainfall data and flow discharge were also analyzed. The results showed that this collapse was different from some previous ones collapsed due to the erosion at the toe of the slope. Khanh waterfall landslide occurred due to the increasing amount of water in cracks and caves in the limestone layer in the slope. The collapse process was simulated based on Coulomb mixture theory. The numerical simulation results show similarities with the actual collapse process. The results provide indicators for assessing the risk of such limestone waterfall landslides in the future. [ABSTRACT FROM AUTHOR]

Early medieval Europe is characterised by a wide spectrum of church sites that contributed in distinct ways to the formation of communities and polities. However, it is challenging for archaeologists and historians to distinguish between them because they often employed the same basic 'grammar' in their layout and architecture, while most of them receive scant attention in the textual sources. It is argued that the most promising approach is a comparative one within a small, well-defined area, as this removes extraneous regional factors so that measurable variables primarily reflect the character, function, and relative importance of the church. This is illustrated by topographical and geophysical surveys of four examples in the northeast of the Irish kingdom of Fir Maige: a substantial landed monastery (Brigown), an ecclesiastical out-farm on its lands (Kildrum), a lesser landed church (Labbamolaga), and a royal community church (Killeenemer). New evidence is presented for the origins of the sites; for their scale, layout, and development; for habitation, agriculture and craft activity; and for ritual practice. This targeted comparative approach greatly refines our understanding of the specific niches they occupied within the settlement hierarchy. [ABSTRACT FROM AUTHOR]

Hyporheic exchange flow (HEF) can generally be quantified through two different approaches. The first approach, which is deductive, entails physically based models, supported with relevant observations. The second approach includes inductive assessments of stream tracer tests using solute transport models, which provide a useful mathematical framework that allows for upscaling of results, but included parameters often have a vague physical base, which limits the possibilities of generalizing results using independent hydromorphological observations. To better understand how the physical basis of HEF‐quantifying parameters relates to stream hydromorphology at different spatial scales, we cross‐validated the results from (a) tracer test assessments using a 1D solute transport model that accounts for HEF and (b) an independent hydromechanical model that represents HEF driven by multiscale pressure gradients along the streambed interface. To parameterize the models, topographical surveys, tracer tests, and streambed hydraulic conductivity measurements were performed in 10 stream reaches, differing in terms of geomorphology, slope, and discharge. The results show that the models were cross‐validated in terms of the average exchange velocity, providing a plausible physical explanation for this parameter in small alluvial streams with low discharges, shallow depth, and moderate slopes. However, the hydromechanical model generally resulted in wider residence time distributions and occasionally higher average residence times compared to the tracer test assessments. From the cross‐validated multiscale hydromechanical model, we learned that water surface profile variations were the main drivers of HEF in all investigated streams and that spatial scales between 20 cm and 5 m dominated the estimated HEF velocity. Key Points: An inductive and a deductive approach for estimating hyporheic exchange velocity were cross‐validated in streams of varying hydromorphologyLongitudinal variation in the water surface profile constituted a major control of hyporheic exchange flow (HEF) in the investigated streamsSpatial scales smaller than five meters are likely important to consider to satisfactory quantify HEF in small streams [ABSTRACT FROM AUTHOR]

In the field of underwater wireless communication, the acoustic signal has the advantages of low attenuation, long propagation distance, and high fidelity compared with electromagnetic wave signals. Therefore, as an important acoustic sensor, the sonar has been widely used in underwater topographical surveying, underwater search and rescue, ship navigation, etc. The sonar image also faces challenge of low-resolution due to its imaging mechanism, like ultrasonic image and synthetic aperture radar image. In this paper, we propose a deeper super-resolution generative adversarial network (DGP-SRGAN) with gradient penalty. It can be used to produce the sonar image with high-resolution. The main contribution of our method is that the gradient penalty is added to the loss function for a more stable and faster training network. The deep of the generator network is doubled from the original 16 layers to 32 layers to make the network more expressive, achieving its better performance. The loss function of the discriminator network increases the gradient penalty term. It can insure a faster network converge and then reach a stable state in less time. Thus the proposed network model achieves a better super-resolution reconstruction effect. The experimental results show that DGP-SRGAN can control the output of super-resolution images well based on input conditions. Meanwhile, the quality of the output image has improved significantly when compared with the other methods. [ABSTRACT FROM AUTHOR]

In areas covered by vegetation, large-scale topographic mapping by UAV oblique photogrammetry normally obtain elevations from vegetation instead of ground points, resulting in lower elevation precision. This study developed an precision improvement grid algorithm and associated SOP for large-scale topographic surveying and mapping in vegetation coverage areas by UAV oblique photogrammetry. The procedures of generating a three-dimensional model for topographical surveying was proposed using Guanlang project as an experimental case study. The UAV flight route and the course overlap and side overlap of UAV oblique photogrammetry were designed, and the image control point layout in the experimental field was carried out. CTI T3 high-precision intelligent RTK was used for image control point measurement. A grid algorithm based on elevation maps was developed and validated in the Guanlang experimental field to improve the elevation precision in vegetation coverage areas. [ABSTRACT FROM AUTHOR]

Remote piloted aircraft systems (RPAS) have become an important tool for the acquisition of geo-referenced information in agriculture. In particular, this technology can be used for land levelling, making agricultural field surveys more efficient and precise. Due to the above, and the need for high resolution cartography, an evaluation of a prototype of RPAS for topographical surveys, based on georeferenced RGB images, including ground control points, was carried out. To this end, an autonomous flight mission was carried out at the experimental field of the Chapingo Autonomous University, Mexico, at an altitude of 20m, with a horizontal speed of 1m/s and winds of no more than 5 km/h, covering an area of 2151 m² (0.23 ha). The RGB images obtained with the RPAS were corrected by means of ground control points and the dense cloud of points generated was compared with a post-processing GPS topographic survey, obtaining absolute and standard errors of 0.020 and 0.024 m, respectively. [ABSTRACT FROM AUTHOR]

The final chapter by Gascoigne, integrating Tinnis into the historical and economic history of the Eastern Mediterranean from the 4th to the thirteenth centuries, shows the extremes of life during this period. Tell Tinnis is an archaeological site in the north-east of Egypt, on an island inside Lake Menzala. While limited archaeological work has been carried out at the site, it is only partially published, and the project led by Alison Gascoigne aimed to record as much archaeological material as possible about Tinnis in seasons between 2004 and 2012. [Extracted from the article]

In mountain basins, long-term instrumental monitoring coupled with high-resolution topographic surveys can provide important information on sediment yield. The Gadria catchment, located in the eastern Italian Alps, typically features several low-magnitude flood episodes and a few debris-flow events per year, from late spring to late summer. Beginning in 2011, sensors devoted to debris-flow detection (geophones, video cameras, flow stage sensors) were installed along the main channel, upstream of a retention basin. In case of debris flows, high-resolution topographical surveys of the retention basin are carried out multiple times per year. Rainfall is measured in the lower part of the catchment and at the headwaters, while passive integrated transponder tracing of bedload was performed in the main channel during spring and summer 2014. In this work, we present the reconstruction of the sediment dynamics at the catchment scale from 2011 to 2017. Results show that (i) coarse sediment yield is dominated by the few debris flows occurring per year; (ii) debris-flow volume estimations may be significantly different--up to 30 percent lower--when performed through a digital elevation model of difference analysis, compared to the timeintegration of the debris-flow discharge estimates; (iii) using this latter method, the volumes are affected by significant uncertainties, particularly for small values of flow depth; and (iv) rainfall analysis permits us to characterize debris-flow initiation but also highlights difficulties in discriminating triggering from non-triggering rainstorms if based on rainfall duration and intensity only. [ABSTRACT FROM AUTHOR]

This article represents a showcase of two different coding approaches with GAMMA, used to calculate topographic and differential phases from high resolution TanDEM-X bistatic data, provided by DLR. First implementation approach comprises "BASH" scripting in Linux environment, having direct control of the GAMMA executables. Second approach is utilization of the "PyroSAR framework" via GAMMA-API, in Python environment. Two resolution scales are used of 4 and 12 meters, to test feasibility of TanDEM-X InSAR output products in mountainous forest in rugged region. First approach allowed thorough processing with abundant GAMMA output, whereas the high scale PyroSAR framework via GAMMA-API showed fast implementation. Comparison over 4 and 12 m resolution products showed good feasibility with strong influence from topography. Intense multi-looking resolved better connection of coherence amplitude to the volume decorrelation in canopy, despite preserving high resolution reveals plenty of details in land cover. Differential height calculation without phase unwrapping showed significance in data processing over mountainous regions. Intensities normalization & terrain flattening showed good performance in both resolution scales. Finally, utilization of GAMMA in InSAR processing of high resolution TanDEM-X bistatic SAR data showed good feasibility and flexibility to derive interferometric products. [ABSTRACT FROM AUTHOR]

We present the results of an archaeoastronomical analysis of structures dating from the Inca and early colonial periods in the Mapocho River basin, Chile. Our purpose is to show possible continuities or ruptures in the creation and management of architectural and natural spaces, particularly those linked to the observation of astronomical phenomena with ceremonial and calendrical significance in the Andean world. We focus on Santiago, where we undertook topographical and horizon survey work at the Main Square, Metropolitan Cathedral, San Francisco Church and Santa Lucía Hill, and evaluate documentary and ethnographic sources. Using models developed in cultural astronomy and landscape archaeology, we found these places were ancient observation spots for the Sun and Moon around the solstices, equinoxes and lunar standstills. Sightlines (ceques) may have connected these places to potentially sacred elements of the environment from a central point located in the Main Square (haukaypata). [ABSTRACT FROM AUTHOR]

Copyright of Revista Chilena de Derecho Privado is the property of Fundacion Fernando Fueyo Laneri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Featured Application: Environmental monitoring of risk areas, deformation control of structures (dams, bridges), topographical surveying, GCP for aerial mapping survey. In this work, the performance of the multi-GNSS (Global Navigation Satellite System) Precise Point Positioning (PPP) technique, in static mode, is analyzed. Specifically, GPS (Global Positioning System), GLONASS, and Galileo systems are considered, and quantifying the Galileo contribution is one of the main objectives. The open source software RTKLib is adopted to process the data, with precise satellite orbits and clocks from CNES (Centre National d'Etudes Spatiales) and CLS (Collecte Localisation Satellites) analysis centers for International GNSS Service (IGS). The Iono-free model is used to correct ionospheric errors, the GOT-4.7 model is used to correct tidal effects, and Differential Code Biases (DCB) are taken from the Deutsche Forschungsanstalt für Luftund Raumfahrt (DLR) center. Two different tropospheric models are tested: Saastamoinen and Estimate ZTD (Zenith Troposhperic Delay). For the proposed study, a dataset of 31 days from a permanent GNSS station, placed in Palermo (Italy), and a dataset of 10 days from a static geodetic receiver, placed nearby the station, have been collected and processed by the most used open source software in the geomatic community. The considered GNSS configurations are seven: GPS only, GLONASS only, Galileo only, GPS+GLONASS, GPS+Galileo, GLONASS+Galileo, and GPS+GLONASS+Galileo. The results show significant performance improvement of the GNSS combinations with respect to single GNSS cases. [ABSTRACT FROM AUTHOR]

Cibaligo river is one of the major rivers that flow in Cimahi city. During the rainy season, the river is often causing a flood, especially in Melong sub-districts. Several mitigation alternatives have been prepared by the Government of Cimahi City, such as normalization of the river, and construct retention pond. This research is aimed to simulate the mitigation plan hydraulically to examine the effectiveness of the plan alternative. The simulation was done using HEC-RAS software for existing conditions and the condition with mitigation alternatives. The input for simulation collected from 3 nearest climatological stations, whereas SRTM, SPOT 6, and Cimahi City land used map used as a physical condition data input of catchment. A topographical survey was done to measure both cross and long sections of the river and used as simulation input of existing conditions. Two dimensional HEC-RAS simulation applied for each mitigation alternatives such as river normalization, construction of detention pond, and combination of both river normalization and retention pond. The simulation shows that the construction of 125 000 m3 retention ponds has a minimal effect. The combination of both river normalization and construction of ±315.000 m3 retention pond can prevent the area from inundation only for 2 years rainfall period; therefore, other mitigation plans have to be prepared to prevent the area from the flood. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos de Investigación Geográfica is the property of Universidad de la Rioja, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper deals with the practical application of photogrammetry in the study of the Roman city of Doclea in Montenegro, with particular reference to the use of Structure from Motion (SfM) techniques. Among the various research areas, archaeology of architecture and settlement archaeology make today an increasing use of photogrammetry for the in-field documentation of archaeological features. This method has an essential role in obtaining a reliable geometric survey that in turn forms the basis for the structural assessment of the architectural heritage thanks to consolidated methods such as archaeological stratigraphy and direct examination. In recent years, digital photogrammetry and the implementation of data processing technologies have made it possible to create three-dimensional models using images acquired through high-definition cameras. In addition to an accurate topographical survey, the aforementioned methods offer the opportunity to obtain a faithful representation of the real world, providing a basis for subsequent architectural and territorial studies. The use of drones equipped with cameras has proved to be particularly effective and capable of detecting large areas quickly and with good results. Due to its versatility and relative ease of use, photogrammetry could actually be deemed as an essential tool for the study and conservation of cultural heritage. [ABSTRACT FROM AUTHOR]

Copyright of Thiasos is the property of Edizioni Quasar di Severino Tognon s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Central Cordillera of Luzon in the Philippines is home to some of the most complex geology, active plate margin tectonism, heaviest rainfall and steepest terrain in the world. It also hosts a thriving agricultural community that has developed its agrarian, municipal and transport infrastructure in a landscape of marginal stability and extreme geomorphological sensitivity. The village of Pilando occupies a saddle on a prominent ridge where it is crossed by the Halsema Highway. As a result of landslide displacements, both the highway and the village have been subsiding for several decades and many dwellings have had to be abandoned. From topographical survey and visual observation, average rates of settlement vary between c. 0.1 and 0.4 m a−1. The apparent depth and areal extent of ground movement are such that attempts to stabilize the area would be both impracticable and uneconomic. Realignment and relocation are options that might be considered but many adjacent slopes are unstable or have failed in the past and those that have not are highly sensitive to earthworks and drainage disturbance. Unfortunately, there are many areas of the Central Cordillera that are affected by similar slope instability problems. The interpretation of satellite imagery available on Google Earth, supported by geomorphological field observation, can assist in the delineation and assessment of these notably unstable areas for land use planning and slope management purposes. [ABSTRACT FROM AUTHOR]

The essay dealing with this subject discusses the potential for using LiDAR scans to study castles and assist in the preservation of historic monuments. Various ways are presented in which the data obtained can be processed using a variety of procedures to produce images. Advantages and disadvantages of presenting graphs in black and white or in colour and the possibility of visualising the relief of the terrain are discussed. Four castles in Lower Saxony are taken as examples: the small but well-preserved motte-and-bailey castle at Trögen, with its striking topography, the Sachsenstein at Bad Sachsa with its complex internal structure, and two castles built at high elevations: Winzenburg Winzenburg and Wohldenberg, in the case of which it is primarily the connection of the castles to their wider surroundings that is of greatest interest. It emerges that the two procedures supplement each other in terms of what they can reveal: while black and white representation is particularly suited to bringing out individual topographical structures, colour is better at highlighting the overall topography. This can be well illustrated by the Sachsenstein, while in the case of Trögen motteand- bailey castle, the differences between topographical surveys and the LiDAR scan are particularly evident. A landscape-based approach to the study of castles is adopted for the Wohldenberg, while the small region around the Winzenburg is used to illustrate the mutual relationships among several sites. These two case studies particularly demonstrate the advantages of LiDAR-supported analysis, but they also indicate avenues for monitoring castles in accordance with the principles underlying the preservation of ancient monuments. [ABSTRACT FROM AUTHOR]

UAVs-Unmanned Aerial Vehicles- also known as drones, are an emerging geospatial technology that can facilitate data acquisition at various temporal and spatial scales. Notwithstanding, the wide application of UAVs globally, its wider application is found to be growing in Nepal as well. For instance, precision agriculture, forestry, topographical surveying, etc. It seems that there is a correlation between efficient use of UAVs in these sectors and the legal frameworks that regulate the use of UAVs. Therefore, it seems necessary to obtain holistic national view of UAVs regulations. Aligning with this necessity, this paper provides insight on existing legal provisions for UAVs in Nepal by highlighting the importance, impact, and limitations of UAV regulations. The criteria used in the framework to capture the present holistic legal dimension from literature in the web of science database are a) applicability b) technical requirements c) operational requirements/ limitations d) administration procedure e) human resource requirements and f) implementation of ethical constraints. The adopted methodological approach consists of exploratory case studies, systematic reviews of the concerned literature on UAVs regulations and the workshop on "Flight 4 Purpose" in which various UAVs application were discussed. The results show that the existing legal framework has both strengths and weaknesses for its use to capture the spatial data. The way forward is to harmonize the soft and hard regulations so that such geospatial technology can be applied for overall development and ultimately for the societal benefits. [ABSTRACT FROM AUTHOR]

This contribution offers an overview of recent fieldwork and museum-based projects focused on the Rhodian countryside and Dodecanese islands. The excavations conducted by the Ephorate of Antiquities of the Dodecanese over the past two decades, paired with the study of Rhodian collections in the Louvre and British Museum, among other museums, have developed and promoted the archaeological record of the region. The Kymissala Archaeological Research Project led by the University of the Aegean and a collaborative doctoral project investigating the British Museum's collections from Kamiros each demonstrate the potential of revisiting historic excavations through topographical surveys and archival documentation. [ABSTRACT FROM AUTHOR]

Modern scanners can perform terrestrial topographic survey with resolution of 1 cm and accuracy of 2 mm in just a few minute's time, from the distance of up to 100 meters. However, for surface topographical surveying of large territories or complex industrial objects, it is necessary to conduct geodetic traverses and perform their binding to the points of the geodesic basis. One method of coordinate transferring during surveying is by using the method of inverse linear-angular intersection, which involves the measuring of the respective sides S1, S2 and the β angle between them. This method is more precise than the classical one, which usually contains centring and reduction errors. The linear-angular intersection method can also be used for many applications in engineering geodesy, for laying geodetic traverses, and for binding to the wall based points of ground-surveying. [ABSTRACT FROM AUTHOR]

Abstract 18 months of at least bi-weekly topographic surveys have been conducted on a 700 m stretch of the meso- to macro-tidal Biscarrosse beach, France. Here we focus on the impact of the short-term dynamics of the beach (a few days) on the seasonal winter response of the beach. The beach was surveyed intensively during two winter seasons and the results indicate that despite similar pre-winter morphology but very contrasting energy levels (the first winter season being 1.7 times more energetic than the second winter season), the sediment budgets over the two winter periods were very similar as well as the cross-shore dynamics of the extracted proxies associated with the dune foot and the berm. The data collected suggest that this may be explained by the sequence of erosion/recovery events driven by hydrodynamic conditions (as the water level and energetic conditions), and sediment transport. Thus, during the first winter, post-storm recovery was effectively driven by energetic conditions while during the second winter, inter-storm conditions did not allow the initiation of recovery in between the storms. Apart from the control from wave conditions, the seasonal beach response is also discussed within the framework of storm chronology and tidal range. Highlights • Similar seasonal sediment budget observed under very contrasting seasonal cumulative wave energy • Post-storm initiated beach recovery not automatically interrupted by the following high energetic conditions due to a storm • Inter-storm wave conditions play a crucial role in the winter seasonal response of the beach [ABSTRACT FROM AUTHOR]

Topographic surveys inevitably contain error, introducing uncertainty into estimates of volumetric or mean change based on the differencing of repeated surveys. In the geomorphic community, uncertainty has often been framed as a problem of separating out real change from apparent change due purely to error, and addressed by removing measured change considered indistinguishable from random noise from analyses (thresholding). Thresholding is important when quantifying gross changes (i.e. total erosion or total deposition), which are systematically biased by random errors in stable parts of a landscape. However, net change estimates are not substantially influenced by those same random errors, and the use of thresholds results in inherently biased, and potentially misleading, estimates of net change and uncertainty. More generally, thresholding is unrelated to the important process of propagating uncertainty in order to place uncertainty bounds around final estimates. Error propagation methods for uncorrelated, correlated, and systematic errors are presented. Those equations demonstrate that uncertainties in modern net change analyses, as well as in gross change analyses using reasonable thresholds, are likely to be dominated by low‐magnitude but highly correlated or systematic errors, even after careful attempts to reduce those errors. In contrast, random errors with little to no correlation largely cancel to negligible levels when averaged or summed. Propagated uncertainty is then typically insensitive to the precision of individual measurements, and is instead defined by the relative mean error (accuracy) over the area of interest. Given that real‐world mean elevation changes in many landscape settings are often similar in magnitude to potential mean errors in repeat topographic analyses, reducing highly correlated or systematic errors will be central to obtaining accurate change estimates, while placing uncertainty bounds around those results provides essential context for their interpretation. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. The analysis of landscape change based on repeat topographic surveys is becoming an increasingly practical and powerful tool across many earth surface disciplines. This paper re‐iterates the importance of accounting for survey error through error propagation, including subtle systematic errors, and presents statistical methods for doing so. The common practice of removing change measurements below some limit of detection ("thresholding") is shown to provide biased and potentially misleading results when used to assess net volumetric or mean change. [ABSTRACT FROM AUTHOR]

Abstract Topography is the expression of both internal and external processes of a planetary body. Thus hypsometry (the study of topography) is a way to decipher the dynamics of a planet. For that purpose, the statistics of height and slopes may be described by different tools, at local and global scale. We propose here to use the multifractal approach to describe fields of topography. This theory encompasses height and slopes and other statistical moments of the field, taking into account the scale invariance. Contrary to the widely used fractal formalism, multifractals are able to describe the intermittency of the topography field. As we commonly observe a juxtaposition of rough and smooth topographies at a given scale, the multifractal framework seems to be appropriate for hypsometric studies. Here we analyze the data at global scale of the Earth, Mars, Mercury and the Moon and find that the statistics are in good agreement with the multifractal theory for scale larger than ∼ 10 km. Surprisingly, the analysis shows that all bodies have the same fractal behavior for scale smaller than ∼ 10 km. We hypothesize that dynamic topography of the mantle may be the explanation at large scale, whereas the smaller scale behavior may be related to elastic thickness. [ABSTRACT FROM AUTHOR]

To establish a basis for the utilization of lidar topography as a data source for coastal geomorphological analyses, this study generated statistical metrics of lidar error through the comparison of a June 2014 USGS collection of airborne lidar with a concurrently collected high-accuracy GPS topographical survey collected within the beach and dunes of a portion of Fire Island National Seashore. The examination of bare earth lidar error within the experiment site revealed a complex association between accuracy and environment within the coastal landscape. Accuracy was constrained to better than 50 cm RMSE in areas with vegetated dune topography and, overall, a 38.9 cm RMSE was measured. Higher accuracies were achieved in the flat, non-vegetated beach. A three-dimensional minimization of residuals between the lidar and GPS surveys reduced the total RMSE to 25.2 cm, indicating a correctable systematic offset between the surface generated from the lidar and the true ground surface. [ABSTRACT FROM AUTHOR]

In this study, we evaluated ‘Crandon’ coarse root biomass and architecture grown at different topographic positions and fertilizer rates. Complete excavations were conducted on a subset of trees after the first growing season and showed that root biomass was strongly related to stem biomass (R2 = 0.93), but not topographic position or fertilizer rate. After the third growing season, subsamples of roots were collected from another subset of trees and showed coarse root architecture variables to be strongly related to several metrics of the tree and root size (R2 = 0.61 to 0.82), while also differing by topographic position. Equations relating root biomass to stem biomass were derived from both methodologies (complete excavation v. subsampling for architecture measurements), and comparison of the equations indicated no difference in slopes (p = 0.59) or intercepts (p = 0.90), although the subsampling approach had a weaker model fit. Our results suggest ‘Crandon’ roots (i) adhere to strong allometric relationships with stem biomass, (ii) alter their architecture within the constraints of this allometric relationship according to site conditions, and (iii) can be subsampled to estimate root biomass from root architecture parameters with similar accuracy (but less precision) compared to complete excavations. [ABSTRACT FROM AUTHOR]

The Specialization School in Archaeological Heritage of the University of Bologna has promoted an archaeological fieldwork for its pupils, focusing on a territorial study aimed at investigating an area in South-East Italy: the Tremiti Islands, in particular San Domino, San Nicola and Capraia. This project aims at better understanding and enhancing this territory through the analysis of the islands geographical layout between being located in front of Apulia's coast and, at the same time, their secluded nature. The first aim was to define the different settlement patterns thorough the various historical periods, on the basis of the material culture and the archaeological evidence collected on the field. The survey activity has been implemented also through significant data elaboration: photogrammetry, topographical surveying, documentation and study of materials, the use of databases and a GIS. The results have confirmed and expanded the previous studies. [ABSTRACT FROM AUTHOR]

THE NEW RELEVANT TECHNOLOGIES APPLIED TO CULTURAL HERITAGE - IN PARTICULAR THE APPLICATION OF THE BIM METHODOLOGY - ALLOW TO BETTER UNDERSTAND THE IMPACTS OF DETAILED PLANNING. GEOMAR, A COMPETENT COMPANY IN ARCHITECTURAL AND TOPOGRAPHICAL SURVEYS, TESTIFIES HOW A CUTTING-EDGE SURVEY CAN MAKE THE DISSEMINATION OF BUILT HERITAGE EVER EASIER. [ABSTRACT FROM AUTHOR]

Digital elevation models (DEMs) have been increasingly applied in topographic studies in areas such as physical geography and hydraulic engineering. Several methods have been proposed to reconstruct DEMs, including classic close-range stereo photogrammetry and the more novel Structure from Motion (SfM) methodology. Past published studies tend to apply SfM to large-scale environmental processes, whilst classic close-range stereophotogrammetry is focusing on detailed small-scale applications. However, SfM requires multiple ground control points (GCPs) to allow for proper DEM scaling. The larger the study area, the more GCPs are required, resulting in increased operational complexity and time-consuming application of SfM. As the accuracy of the DEM depends on the equipment used to measure GCPs, this can also result in a cost-expensive operation. In the present study, we introduce a combined SfM and close-range stereo photogrammetry application, with the close-range stereo photogrammetry results serving as a control for providing scale, thus eliminating the need for traditional GCPs. To validate our methodology, we studied a 40 m long gravel bar. We used GoPro Hero 3 cameras for SfM measurements and replaced GCPs by DEMs obtained through close-range stereo photogrammetry with a Nikon D5100 camera pair in stereo. In addition to using photo-mode frames, we also studied the quality of DEMs obtained with GoPro Hero 3 video-mode frames, and show how the DEM quality is reduced due to the smaller image format, hence coarser point cloud spacing, which eventually results in a convex curvature when image overlap was increased. Our results show that it is possible to collect high-quality topographic surface data by only using cameras, and alleviate the need for GCPs. The proposed workflow reduces the complexity, time, and resource demands associated with deploying GCPs and necessary independent geo-referencing, ensuring that digital photogrammetry will continue to gain popularity for field surveying. [ABSTRACT FROM AUTHOR]

Abstract With a little more than 100 years since the publication of seminal and field-defining investigations, active tectonics is still a relatively young sub-discipline of structural geology. This research field addresses the accumulation of strain due to plate tectonic motion and more importantly release thereof through the occurrence of earthquakes (or other strain-releasing events). In that regard, active tectonics aims to characterize the incremental steps of plate tectonics. Determining earthquake chronologies, fault slip rates, and other common objectives importantly feed into our understanding of, for example, fault mechanics and crustal rheology. Characterizing the recurrence of large and potentially devastating earthquakes, is further motivated by seismic hazard assessment and risk mitigation. The primary data source in active tectonics is surface and shallow subsurface evidence of faulting –presenting itself in topographic and stratigraphic data sets respectively. Field observations and air photo interpretation of displaced stratigraphic and geomorphic markers were used almost 40 years ago to formulate end-member models of earthquake recurrence. Technological developments since then –especially within the last two decades– have dramatically increased the abundance and resolution of topographic data sets and the ability to date stratigraphic units and geomorphic surfaces, enabling the formulation of better-informed conceptual models of earthquake recurrence. Here, we provide an overview of the high-resolution topographic data sets and dating methods that enabled the recent advances of active tectonics. Graphical abstract Image 1 Highlights • Advances in active tectonics in 4D, spatially 3D plus temporal dimension. • Overview of global and local topographic data sets and obtaining methods. • Advances in Quaternary dating methods. [ABSTRACT FROM AUTHOR]

Highlights • Snow damages to canopy increases seedling richness and abundance via recruitment. • Most of the high-recruiting seedlings are light demanding species. • Topographic habitat and spatial pattern also affect seedling composition. Abstract We investigated the relative and combined effect of topography and light environment on the recruitment of seedlings in a subtropical forest after snow damage to the canopy. The tree seedling community in an old-growth subtropical forest was monitored using 500 2 m × 2 m seedling plots at six-month intervals for 2 years. With a focus on recruitment following canopy damage, we related abiotic and biotic environmental variables to seedling dynamics, and we tested if significant topographic and light habitat associations were present for seedlings recruiting via a torus translation test. Then, we used variance partitioning to examine the relative effects of spatial, topographic and light variables on the temporal assemblages of seedlings. A total of 3047 seedlings from 58 species recruited in the first 2 years following snow damage. At the community level, increases in seedling abundance and richness were positively correlated with canopy openness and negatively correlated with elevation. At the species level, both pioneer and late-successional tree species had more recruits in high light environment than in low light environment. 84.3% of the recruiting seedlings were significantly associated to either light environment (35.7%), topography (26.5%) or both (22.1%). Despite this, at the plot level, spatial variables (PCNM) explained the majority of the variability in seedling composition over time. Our results suggest that snow damage to the canopy increases species richness and abundance via light-facilitated seedling recruitment, and that the composition of recruiting seedlings was largely spatially dependent. Topographic habitat filtering acts as a persistent force in determining the recruitment of seedlings and increases in strength with increased light-facilitated seedling recruitment. Our results highlight that, in this subtropical forest, both light requirement and topographic specialization interact over time to play a key role in promoting coexistence of tree species through selection of individuals at the seedling stage. We also suggest exploring the possibilities of management intervention to speed up the recovery of this forest. [ABSTRACT FROM AUTHOR]

The topographical suitability assessment of human settlements (SAHS) creates a solid foundation for regional population distribution and socio-economic development. Local elevation range (LER) is an important factor that can be used to assess the suitability of different terrains for sustaining human settlements. However, current digital elevation model (DEM)-based LER products suffer from some challenges typically because of their subjectively selected neighborhood scales and coarser spatial resolution. In this study, we initially determined the optimal statistical window and then calculated the appropriate LER with the finer resolution data of the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global DEM (ASTER GDEM) products for China. Then, the appropriate LER was used to evaluate the topographical SAHS and its correlations with the national gridded population distribution (1 km × 1 km) in 2010. The results show that the optimal statistical window for calculating a 1 arc-second (about 30 m) resolution GDEM LER for China can be determined using a 51 × 51 grid unit (width × height) within a rectangular neighborhood, corresponding to an area of about 2.34 km2. Secondly, the LER values in the southern and western China were greater than those of the north and east, showing a trend which consistently reflects the general spatial features of landforms. Finally, the relationship between GDEM LER and population density was highly correlated with the R2 value of 0.81. It showed that 85.22% of the Chinese population was located in areas where the LER is lower than 500 m. The topographically suitable area within China decreased from the southeastern coastal zone towards the northwestern inland areas due to transition from plains and basins to plateaus and mountains. The total area of moderate to high suitable level was 423.84 × 104 km2, or 44.15% of the total land area, with 88.17% of the national population. Our study demonstrates the usefulness of appropriate LER in evaluating the topographical SAHS as well as its significant impact on population distribution. [ABSTRACT FROM AUTHOR]