Digital Elevation Model is imperative to many earth surface process analyses. In this study, the quality of DEMs acquired by SRTM ver.3 and ASTER ver.2 is evaluated. The reference levels produced ...from GPS elevations, and the topographic map is used to assess the vertical accuracy of SRTM and ASTAR DEMs in Najran city, Saudi Arabia. The GPS reference elevations gave us the values of ±5.94m and ±5.07m for used SRTM and ASTER DEMs. Also, by using elevation from the topographic map as a reference elevations the obtained accuracy was ±6.87m and ±7.97m for SRTM and ASTER DEMs. For our study area, the 30m SRTM elevations data featured a much greater absolute vertical accuracy than the absolute vertical accuracy value of ±16m, which published in the SRTM data specification.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study investigates the intricate and enduring interplay of historical events, human activities, and natural processes shaping the landscape of North European Plain in western Poland over ...230 years. Topographic maps serve as reliable historical data sources to quantify changes in forest, grassland, and wetland areas, scrutinizing their fragmentation and persistence. The primary objectives are to identify the permanent areas of the landscape and propose a universal cartographic visualization method for effectively mapping these changes. Using topographic maps and historical data, this research quantifies land cover changes, especially in forest, grassland, and wetland areas. With the help of retrogressive method we process raster historical data into vector-based information. Over time, wetlands experienced a substantial reduction, particularly in 1960-1982, attributed to both land reclamation and environmental factors. Grassland areas fluctuated, influenced by wetland and drier habitat dynamics. Fragmentation in grassland areas poses biodiversity and ecosystem health concerns, whereas forested areas showed limited fluctuations, with wetland forests nearly disappearing. These findings highlight wetland ecosystems' sensitivity to human impacts and emphasize the need to balance conservation and sustainable development to preserve ecological integrity. This study advances landscape dynamics understanding, providing insights into historical, demographic, economic, and environmental transformations. It underscores the imperative for sustainable land management and conservation efforts to mitigate human impacts on ecosystems and biodiversity in the North European Plain.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Lakes are sensitive indicators of anthropogenic climate change and also respond to direct human activities. Yet, long-term lake inventories and quantitative evaluation of the factors driving observed ...lake changes across China remain elusive. Here, for the first time, we examined multi-decadal lake area changes in China during 1960s–2015, using historical topographic maps and >3831 Landsat satellite images, including lakes as fine as ≥1 km2 in size. In addition, we quantified the causes of lake changes from climatic and anthropogenic factors. The total area of lakes in China has increased by 5858.06 km2 (9%) between 1960s and 2015, and with heterogeneous spatial variations. Lake area changes in the Tibetan Plateau, Xinjiang, and Northeast Plain and Mountain regions reveal significant increases of 5676.75, 1417.15, 1134.87 km2 (≥15%), respectively, but the Inner-Mongolian Plateau shows an obvious decrease of 1223.76 km2 (22%). We find that 141 new lakes have appeared predominantly in the arid western China; but 333 lakes, mainly located in the humid eastern China, have disappeared over the past five decades. We conclude that climate factors have played a dominant role in lake changes across China, coupled with noticeable anthropogenic contribution of ~35% in the Eastern Plain and Yunnan-Guizhou Plateau. This study has substantial implications to improve decision support regarding water-resource management strategies and land-use planning throughout China.
•Produced a comprehensive China lake dataset from the 1960s to 2015•Total lake area increased by 9% over five decades with evident regional differences•New lakes and lake area expansion in the arid western China due to climate change•Disappeared and shrinking lakes in the humid eastern China due to human activity
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Efficient sensory processing of spatial information is facilitated through the organization of neuronal connections into topographic maps of space. In integrative sensory centers, converging ...topographic maps must be aligned to merge spatially congruent information. The superior colliculus (SC) receives topographically ordered visual inputs from retinal ganglion cells (RGCs) in the eye and layer 5 neurons in the primary visual cortex (L5-V1). Previous studies suggest that RGCs instruct the alignment of later-arriving L5-V1 inputs in an activity-dependent manner. However, the molecular mechanisms underlying this remain unclear. Here, we explored the role of NMDA receptors in visual map alignment in the SC using a conditional genetic knockout approach. We leveraged a novel knock-in mouse line that expresses tamoxifen-inducible Cre recombinase under the control of the
gene (
), which we show allows for specific recombination in the superficial layers of the SC. We used
mice of either sex to conditionally delete the obligate GluN1 subunit of the NMDA receptor (SC-cKO) during the period of visual map alignment. We observed a significant disruption of L5-V1 axon terminal organization in the SC of SC-cKO mice. Importantly, retinocollicular topography was unaffected in this context, suggesting that alignment is also disrupted. Time-course experiments suggest that NMDA receptors may play a critical role in the refinement of L5-V1 inputs in the SC. Together, these data implicate NMDA receptors as critical mediators of activity-dependent visual map alignment in the SC.
Alignment of topographic inputs is critical for integration of spatially congruent sensory information; however, little is known about the mechanisms underlying this complex process. Here, we took a conditional genetic approach to explore the role of NMDA receptors in the alignment of retinal and cortical visual inputs in the superior colliculus. We characterize a novel mouse line providing spatial and temporal control of recombination in the superior colliculus and reveal a critical role for NMDA expression in visual map alignment. These data support a role for neuronal activity in visual map alignment and provide mechanistic insight into this complex developmental process.
Mapping based on open data sources in digital form represents a revolution in geoinformatics science and practice. Traditionally, the mapping approach required significant material resources and ...expertise to create accurate and up-to-date maps. With the development of geographic information systems (GIS) and an increasing number of websites that provide free access to a huge volume of geospatial information, this way of mapping is becoming more and more present. Open data sources, often free or at low cost, support the download or use of global geospatial data. This enabled the spread of geographical knowledge and skills at a much higher level, including individuals, organizations and social communities. Open data sources provide new mapping opportunities, enabling better understanding and solving complex problems in different fields. The paper systematizes knowledge and techniques from this area and, on the example of the Military Geographical Institute, shows the need for both the use and sharing of such data.
Accurate, precise and rapid acquisition of topographic data is fundamental to many sub-disciplines of physical geography. Technological developments over the past few decades have made fully ...distributed data sets of centimetric resolution and accuracy commonplace, yet the emergence of Structure from Motion (SfM) with Multi-View Stereo (MVS) in recent years has revolutionised three-dimensional topographic surveys in physical geography by democratising data collection and processing. SfM-MVS originates from the fields of computer vision and photogrammetry, requires minimal expensive equipment or specialist expertise and, under certain conditions, can produce point clouds of comparable quality to existing survey methods (e.g. Terrestrial Laser Scanning). Consequently, applications of SfM-MVS in physical geography have multiplied rapidly. There are many practical options available to physical geographers when planning a SfM-MVS survey (e.g. platforms, cameras, software), yet, many SfM-MVS end-users are uncertain as to the errors associated with each choice and, perhaps most fundamentally, the processes actually taking place as part of the SfM-MVS workflow. This paper details the typical workflow applied by SfM-MVS software packages, reviews practical details of implementing SfM-MVS, combines existing validation studies to assess practically achievable data quality and reviews the range of applications of SfM-MVS in physical geography. The flexibility of the SfM-MVS approach complicates attempts to validate SfM-MVS robustly as each individual validation study will use a different approach (e.g. platform, camera, georeferencing method, etc.). We highlight the need for greater transparency in SfM-MVS processing and enhanced ability to adjust parameters that determine survey quality. Looking forwards, future prospects of SfM-MVS in physical geography are identified through discussion of more recent developments in the fields of image analysis and computer vision.
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DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Transportation infrastructure, such as road or railroad networks, represent a fundamental component of our civilization. For sustainable planning and informed decision making, a thorough ...understanding of the long-term evolution of transportation infrastructure such as road networks is crucial. However, spatially explicit, multi-temporal road network data covering large spatial extents are scarce and rarely available prior to the 2000s. Herein, we propose a framework that employs increasingly available scanned and georeferenced historical map series to reconstruct past road networks, by integrating abundant, contemporary road network data and color information extracted from historical maps. Specifically, our method uses contemporary road segments as analytical units and extracts historical roads by inferring their existence in historical map series based on image processing and clustering techniques. We tested our method on over 300,000 road segments representing more than 50,000 km of the road network in the United States, extending across three study areas that cover 42 historical topographic map sheets dated between 1890 and 1950. We evaluated our approach by comparison to other historical datasets and against manually created reference data, achieving F-1 scores of up to 0.95, and showed that the extracted road network statistics are highly plausible over time, i.e., following general growth patterns. We demonstrated that contemporary geospatial data integrated with information extracted from historical map series open up new avenues for the quantitative analysis of long-term urbanization processes and landscape changes far beyond the era of operational remote sensing and digital cartography.
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•Knowledge on the long-term road network evolution is limited due to a lack of data.•Our proposed method extracts past road networks from historical maps automatically.•We integrate contemporary road data, image analysis and unsupervised classification.•We test our method for 50,000 km roads on 42 historical maps in the US since 1890.•The extracted, historical urban and rural roads are highly accurate and plausible.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
New verticals within the Internet of Things (IoT) paradigm such as smart cities, smart farming, or goods monitoring, among many others, are demanding strong requirements to the Radio Access Network ...(RAN) in terms of coverage, end-node's power consumption, and scalability. The technologies employed so far to provide IoT scenarios with connectivity, e.g., wireless sensor network and cellular technologies, are not able to simultaneously cope with these three requirements. Thus, a novel solution known as Low Power - Wide Area Network (LP-WAN) has emerged as a promising alternative to provide with low-cost and low-power-consumption connectivity to end-nodes spread in a wide area. Concretely, the Long-Range Wide Area Network (LoRaWAN) technology is one of the LP-WAN platforms that is receiving greater attention from both the industry and the academia. For that reason, in this work, a comprehensive performance evaluation of LoRaWAN under different environmental conditions is presented. The results are obtained from three real scenarios, namely, urban, suburban, and rural, considering both dynamic and static conditions, hence a discussion about the most proper LoRaWAN physical-layer configuration for each scenario is provided. Besides, a theoretical coverage study is also conducted by the use of a radio planning tool considering topographic maps and a precise propagation model. From the attained results, it can be concluded that it is necessary to evaluate the propagation conditions of the deployment scenario prior to the system implantation in order to reach a compromise between the robustness of the network and the transmission data-rate.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Many critical policy decisions, from strategic investments to the allocation of humanitarian aid, rely on data about the geographic distribution of wealth and poverty. Yet many poverty maps are out ...of date or exist only at very coarse levels of granularity. Here we develop microestimates of the relative wealth and poverty of the populated surface of all 135 low- and middle-income countries (LMICs) at 2.4 km resolution. The estimates are built by applying machine-learning algorithms to vast and heterogeneous data from satellites, mobile phone networks, and topographic maps, as well as aggregated and deidentified connectivity data from Facebook. We train and calibrate the estimates using nationally representative household survey data from 56 LMICs and then validate their accuracy using four independent sources of household survey data from 18 countries. We also provide confidence intervals for each microestimate to facilitate responsible downstream use. These estimates are provided free for public use in the hope that they enable targeted policy response to the COVID-19 pandemic, provide the foundation for insights into the causes and consequences of economic development and growth, and promote responsible policymaking in support of sustainable development.
The Chang'E-2 (CE2) lunar orbiter was the second robotic orbiter of the Chinese Lunar Exploration Program, as well as the pioneer robotic orbiter in the soft landing project in the second phase of ...the program. It used a two-line stereo camera to acquire stereo images with global coverage at a resolution of 7 m. The stereo images have a large potential for producing the best lunar topographic map. However, errors and uncertainties in the interior orientation (IO) and exterior orientation (EO) parameters of the camera seriously affected the accuracy of the global topographic mapping. In this paper, a global adjustment method is proposed to eliminate the effects of these errors. The error models are represented by a Chebyshev polynomial. The polynomial coefficients were estimated as unknowns using five lunar laser ranging retroreflector (LRRR) points as ground control points in the adjustment. The experimental results show that the planimetric and height deviations between the neighboring strips were 5 and 2 m (less than 1 pixel), respectively, which were decreased by 32.6 and 31.5 times, respectively, relative to those derived from the original EO parameters. The large inconsistencies in the CE2 trajectory data were significantly reduced after the adjustment. In comparison with the LRRR positions, the planimetric and height errors ranged from 21 to 97 m and −19 to 10 m, respectively. A new seamless mosaic and high precision absolute position topographic map has been generated using this method.
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