Digital Relief Model Research Articles

Excursion into the history of relief imagery on geographic maps

The purpose of this article is to acquaint geographers with the history of transforming the ways depicting the relief on geographical maps in different countries of the world in order to optimize the choice of methods and techniques for working with old maps. Basic material. An unequivocal, balanced and objective representation of the terrain is one of the main tasks of cartography. However, the representation of a three-dimensional element, which is a relief on a horizontal plane, is a problem that for centuries caused scientific controversy among geographers, cartographers, mathematicians and required new and new attempts to improve the image of this element on the maps. The article examines the retrospective of relief visualization development over the past thousand years. The authors highlight advantages and disadvantages of each of the applied methods of depicting the relief on geographical maps over the centuries. First of all, such as conditional-prospective and profile-silhouette ones. The article gives examples of these methods application in cartography. The study considers a place and role of Kharkiv scientists in the process of forming the doctrine of digital relief models. Conclusions. Having analyzed the history and modernity in the field of relief visualization, it is possible to extrapolate its prospects for the future. Thus, the prospects may include improved resolution and detailing of input and output information, as well as the further development of techniques and methods for dynamic visualization of the terrain, which changes under the influence of adverse anthropogenic and natural (exo- and endogenous) processes and phenomena in real time

Hydrological and morphological features and geoecological condition of the territories of the plains area of the Kuma River valley and their significance in the system of civilizational development of the Central Pre‐Caucasus in the 18<sup>th</sup>–21<sup>st</sup> centuries

Aim. In this work, the main aim was a retrospective analysis of the geo‐ecological state and problems of natural territorial complexes (NTC) of the valley of the plains area of the Kuma River in the context of hydrological and morphological dynamics for the period from the 18th century to the present.Material and Methods. The paper analyses the state of the landscape’s natural components in the region, for which topographic, sectoral and cadastral maps, digital relief model, satellite images were used. Openly available data of ministries, departments, archival and stock materials were used. The degree of anthropogenic transformation of the natural‐territorial complexes was calculated based on the coefficient of ecological stability of landscapes.Result. Using the example of the plains area of the Kuma River for the period of the 18th‐21st centuries, the geo‐ecological features of valley NTC were analysed. Studies have shown that at the present stage meandering remains an important condition for land use in the Kuma River valley in terms of both agricultural land and residential areas. Cartographic schemes of land use of a modelled plot in the valley of the Kuma River were constructed, allowing the assessment of the efficiency of the economic use of the fields of oxbow lakes.Conclusion. For the last two hundred years, valley NTC have remained significant for settlement purposes and related economic activities. The modern meandering belt together with the fields of the older such features create special environment forming conditions for the functioning of the stabilising components of the landscape, floodplain forest being a basic integral factor in the preservation of regional biodiversity. It is recommended that when organising the sustainable use of the land resources of river valleys for the purposes of territorial planning, the regional features of placement of meanders and oxbow lakes be taken into account.

SPLINE MODEL OF GRIDDED DATA OPERATION AS A PRINCIPLE OF ELECTRONIC MAPPING SEABED TOPOGRAPHY

The influence of technologies of automated processing of hydrographic survey results on the potential of the human factor in the transformation of polygraphic cartographic products into digital ones is analyzed. When configuring the digital bathymetric model, the concept of the navigation surface is used as a perspective principle of automated mapping. The approach to the problem of generating bathymetric contours from measurement results in the navigation surface paradigm is construed on continuous spline interpolation of geospatial data for reasonable cartographic generalization when creating electronic cartographic products. From the theoretical positions of the spline approach, the subjectivity of the method of artificial displacement of generalized isobaths to deep-water areas is excluded when creating a safe digital model of the bottom relief, interpreted in a mathematical sense as a navigational isosurface. The principle of electronic mapping based on the use of a spline in tension as an effective approach for the process of generalizing isobaths in order to obtain a wide range of morphometric characteristics of underwater topography has been developed. The generalized line of the active depth contour is estimated in the form of algorithmic reproduction on electronic charts of the safe convexity of the isobate towards the deep-sea area due to the practical implementation of the B-spline “snake model” by analogy with the serpentine configuration of the bathymetric isoline in the form of a piecewise polynomial function. When using the spline approach, an innovative principle of electronic mapping of the underwater landscape based on operating with a set of gridded data is implemented. The latter are interpreted as the results of depth measurements with the formalization of a two-dimensional frame of fixed values of bathymetric measurements for their representation as a navigational isosurface in three-dimensional Euclidean space. The actual synthesis of the seabed topography is implemented on the basis of a proven hybrid spline model for a specific indicative test case based on the processing of experimental gridded data. Hypothetically, the possibility of intellectual assistance to the watch officer in the strategy of instant orientation in conditions of a minimum depth reserve under the keel is organized when using computer three-dimensional visualization of the topography of the underwater relief in an unaffiliated graphic environment with foreign software.

СТВОРЕННЯ ЦИФРОВОЇ МОДЕЛІ РЕЛЬЄФА ДНА

Scientific research considers the efficiency of digital technologies for processing hydrographic information. The form of presentation of data in a digital model and the type of technical data carrying, on which data are registered, focused on the goal of compact saving of the results of the capture and their transfer to different partners for the selection of their software and technical problems. Such an algorithm in every competitive situation, especially in conditions of a strongly divided bottom line, should have a property to find an appropriate equivalent between the detail of reflection of the relief in this scale, which provides the same status of peaks and falls and is a priority of the minimum depth, which is intended to ensure the safety of navigation. Information about navigational problems and the camp of depths in these areas can be seen on the appropriate navigational charts. But in the surrounding areas of the sea with a folding relief of the bottom, knowledge of only point-holes is not enough for the safe navigation of ships. A more detailed picture can be taken from the digital model of the bottom topography, in order to give a more accurate description, character and understanding of the bottom navigational problems. The development of a digital model is possible based on the results of hydrographic surveys. In this article, the theoretical and practical aspects of the research and the real picture of the bottom topography of the ship-floating water areas are considered. The effectiveness of digital technologies for processing hydrographic information is rich in what lies in the set organization of digital data. For the making of the digital relief model, a tree data structure was adopted. Keywords: digital model, hydrographic survey, hydroacoustic survey, seabed relief, sea navigation map, survey sea lines, software hydrographic survey.

Identification of historical trackways in forests using contextual geospatial analyses

AbstractThis article demonstrates the application of the methods unravelling microtopographic features, specifically, sunken linear landforms indicating remains of historical trackways in forests. These are related to the ‘Magna Via’ route in the vicinity of the Deserted Castle and the Peťuša Castle in Central Slovakia. The microtopography validation dataset indicating sunken linear landforms was used to evaluate the data overlap of tracks identified by the global positioning and navigation system (GNSS) and a model of tracks created with the least cost path (LCP) algorithm. Microtopographic features derived from a digital relief model generated by high‐resolution Light Detection and Ranging (LiDAR) scans (density of 5 points/pixel) allowed us to determine the exact position (submeter total vertical and horizontal accuracy) of certain segments of the GNSS tracks and LCP overlapping the sunken linear landforms. Moreover, the LCP model shows the most efficient trackways considering the travel costs depending on the slope parameter.

Current State of the Gold Mining Waste from the Ores of the Ursk Deposit (Western Siberia, Russia)

The article presents the original results of the investigation of sulfide-bearing mine tailings dumps (Ursk, Western Siberia, Russia), the adjacent territory, and acid mine drainage flows. The novelty of this study is related to integration of geophysical and geochemical data. The geoelectrical structure of the dump and the drainage valley was determined using the electrical resistivity tomography (ERT) method. Magnetic anomalies above the surface of the site were identified using ground magnetic surveys. The orthophotomap and a digital elevation model were obtained on the basis of aerial photography from an unmanned aircraft. The model of thermal imaging allows us to identify a number of temperature anomalies in the upper part of the dump slope and filtration zone in the drainage valley, caused by exothermic reactions. The digital relief model was constructed comprising three zones: (1) oxidation, (2) leaching, and (3) mixing and dilution. The oxidation zone is marked by low electrical resistivity (1–10 Ω·m), low pH values of the drainage waters (pH 3.61), low values of the modulus of the magnetic induction vector, and heating by +5 °C compared to the solid dump material that is not actively exposed to water. The oxidative conditions and low pH values favor the dilution of the Fe2+ compounds in the drainage solutions, which also contain Cu (3000 μg/L), Pb (1200 μg/L), As (1300 μg/L), and Hg (34 μg/L). The zone of the primary geochemical barrier is formed within the first 400 m, where the major proportion of dissolved elements if deposited. The second iron–aluminum sorption geochemical barrier is formed at a distance of 1000 m at the mixing zone with the Ur River. The stable geochemistry of surface waters, formed due to the inflow of drainage waters into the Ur River and further into the reservoir, persists at a distance of up to 7.7 km from the dump.

Диагностика состояния почвенного покрова государственного природного заказника «Цимлянский» и процессов эрозии песков

A study of the composition of the soil cover of the territory of the state nature reserve "Tsimlyansky" was conducted in order to track the state of the ecosystem by the main processes of soil formation and indicators of the state of vegetation cover: humus accumulation, the formation of a differentiated profile, projective coverage and the presence of loose sands. The field stage of the study was carried out with the laying of soil sections on sites reflecting the main forms of meso- and microrelief. Samples from each genetic horizon were selected in soil sections for laboratory study of granulometric composition, humus content, nitrogen, phosphorus and potassium content. According to remote sensing data, an assessment of the depth of groundwater occurrence was carried out, a digital relief model and a surface runoff model were built to track probable zones of water erosion of sands. According to the multispectral survey by SWIR-NIR-RED channel synthesis, the areas of loose and loosely anchored sands during the growing season were estimated, the danger of deflationary destruction of the sand massif was estimated. Based on the data obtained, maps of groundwater occurrence, surface runoff and loose sands are constructed. The results of the conducted studies allow us to conclude that the level of resistance to erosion processes is safe for the ecosystem, however, the safety margin of the measures carried out decades ago is approaching a dangerous level, which requires the planting of new protective forests and shrubs to restore the most effective sand retention system. Keywords: GIS, REMOTE SENSING, TSIMLYANSKY NATURE RESERVE, VEGETATION COVER, SOILS, SOIL COVER, SAND MASSIFS

The Wave Climate of the Sea of Azov

This article describes the results of the retrospective numerical simulation of wind waves in the Sea of Azov using the SWAN spectral wave model and the ERA-Interim global reanalysis for 1979–2019. A digital model of the sea-floor relief of the Sea of Azov was used for the calculations. This model was built using a bathymetric map of the Sea of Azov, as well as nautical charts and remote sensing data. Verification of the model for the conditions that characterize the Sea of Azov was conducted using data from ship observations of wind waves. The features of the mean long-term wind wave patterns, as well as the seasonal, interannual, and interdecadal dynamics were presented. The main focus was on the following parameters: significant wave height, wave period, and wave direction. A description of storm conditions and a comparison with surge phenomena and ice conditions was also completed. The results indicated that, in contrast to Taganrog Bay, the wave patterns were heavily influenced according to the time of year (i.e., the seasons). The maximum wave heights were typical for the cold season of the year but not for the ice-free period. The interannual dynamics of wind waves were characterized by the alternation of three five-year periods of strengthening and weakening of wind waves. After 2002, the wave height increased in the summer and autumn seasons and slightly decreased in winter and spring. A shift of the storm season to a warmer period was also detected.

Картографическое обеспечение идентификации природных и техногенных источников растворенного вещества в бассейне озера Байкал

A method of GIS mapping was developed to identify and assess the contributions of sources of matter to the composition of surface waters. The basis for the creation of the GIS database was the results of the study of the spatial diversity of the chemical composition of surface waters. Geoinformation analysis included the creation of a digital framework for mapping, vectorization of mapping sources and Earth remote sensing materials, creation of a single database combining cartographic, statistical information and field observation materials, morphometric relief analysis based on a digital relief model, creating a landscape basis for base maps, creating thematic maps, analyzing changes in the components of geosystems, creating electronic cartographic layers allowing to identify participation of solute sources in formation of water composition. The analysis of component changes was based on the results of different-time studies of the composition of water and bottom sediments. Based on the comparison of the chemical composition of the waters of the Baikal tributaries with the chemical and mineralogical composition of rocks, an approach was developed to identify sources of solute and assess their contributions to the formation of macro- and microelement compositions of surface waters. To solve the problems of the study, methods of statistical analysis of data, multicomponent mixing using systems of linear equations, field methods of data collection were used. Three main categories of solute sources (silicate, sulfide-containing silicate, carbonate rocks) were identified and their contributions to the chemical composition of water were calculated. On the basis of microelement tracers, the contributions of silicate rocks were divided into contributions of primary and secondary silicate rocks, ore-containing silicate rocks without sulfides were isolated. By comparing the ratios of concentrations of trace elements in the waters of uncontaminated territories and wastewater of enterprises, tracers were identified that made it possible to identify sources of surface water pollution. Maps of territories that determine a certain chemical composition of surface waters were compiled, which was first classified on the basis of the ratio of the contributions of drained rocks.

Geomechanical monitoring of pit edge massif deformations of open-pit coal mines on ground-based laser scanning

The laser scanning method, used in combination with traditional mine surveying observations, is one of the most effective and safe ways to conduct surveying and instrumental observations on deforming areas of open-pit mining facilities. The article presents the results of ground-based laser scanning of the “Haranutsky” coal pit and performs a comparative analysis to determine the deformations and displacements of the open pit side for different periods, which was performed in the RISCAN PRO environment. Digital Relief Models (DRM) were constructed to distinguish the observation cycles by colors. Based on the results of the monitoring, it was concluded that no critical displacements and deformations were detected, despite the places of small scree deposits in the rock massif, and further systematic observations were recommended.

Создание модели речной сети для тематической карты с помощью ГИС-технологии

The issues of creating a model of the Mongolian river network as a basis for thematic maps using GIS technologies are highlighted. The characteristic of the river network of Mongolia is considered, be-cause when constructing a digital model, it is necessary to convey its density and structure. Digital re-lief models (DEM) are widely used in the creation and updating of hydrological models of the surface. As the initial information for the creation of the DEM of Mongolia, the satellite images of SRTM of spatial resolution with a step of 30x30 square meters, which are used, are in the public domain. On the basis of this DEM, a new model has also been created of the river-only commercial network of the Khentii district of the Aimag of outer Mongolia for thematic mapping by means of GIS technologies. The order of the river distribution network development was determined by the features of the Strahler method in ArcGIS Spatial Distribution Analyst using special tool "Hydrology". As the result of study a vector hydrographic economic model with a database containing information on river networks is cre-ated. The object of the study is the river network of the Khentii district of the Aimag of outer Mongo-lia, belonging to the Pacific Basin.

Digital model of the «Carbon test site in Krasnodar region» on the base of SBIO RAS (Gelendzhik)

An aerophotography of the experimental area on the Tuaphat massif (area of 6 ha, SBIO RAS) and a bathymetric survey of the adjacent water area have been made within the framework of the “Carbon test site in Krasnodar Region” development. Digital relief models (DRM) of the test site onshore and offshore components were developed based on the survey results. The article presents the methods of work and graphical representation of the developed DRM.

Определение подтопленных территорий с использованием гис-моделирования гидрологических процессов

Проведено исследование методики геоинформационного моделирования подтопляемых территорий речной долины. Создана анимационная ГИС-модель затопления исследуемого объекта - участок долины р. Есиль близ г. Петропавловска (Северо-Казахстанская область), что подвергается ежегодным интенсивным затоплениям. Моделирование сценария производилось на основе гидрологических характеристик, информации об уровнях поднятия воды за определенный период, а также данных о рельефе с использованием инструментариев ArcGIS ArcScene. Использованные методы - сравнительно-географический, картографический, наблюдение, полевые методы, ГИС-технологии. Исследование состоит из нескольких этапов, которые включают следующие задачи: сбор и обобщение аналитических данных о гидрологическом режиме, весеннем половодье, паводковых явлениях на р. Есиль, создание цифровой модели рельефа по данным SRTM, создание прогнозной модели затопления вблизи г. Петропавловска. Полученные результаты могут быть полезны для планирования и проведения мероприятий по предупреждению чрезвычайных ситуаций, связанных с паводковыми явлениями на реке.

Опыт компьютерного моделирования паводкового стока реки Кубань к Краснодарскому водохранилищу на основе модели DWAT

The article is dedicated to PC modeling of the maximum water runoff of the Kuban rivers flowing to the Krasnodar reservoir after the storm rains. A mathematical model of the «precipitation-runoff» type – DWAT was used. This model is recommended by the World Meteorological Organization for use on rivers with flash floods, based on river survey digital elevation models and storm rain forecasts. A possibility of using proposed approach, the estimated possibility of using DWAT for short-term forecasting of flood inflow to the Krasnodar reservoir based on storm precipitation at predictor meteorological stations, which is tentatively assessed based on the analysis of the dependence of the main elements of floods on the storm rain characteristics. In addition to the digital relief model, the model uses georeferenced layers of data on vegetation, land use types and soils of the catchment area. In general, the article shows the process of entering and processing data into the model. The obtained final simulation results, expressed by the forecast hydrograph, are compared with the observed true values. The forecasted flood graphs correspond suffi ciently to the observed ones and in general the ma ximum water discharges of the forecasted floods obtained using the model under study for previous precipitation are for the most part slightly higher than the observed ones, which is partly explained by the spatial data due to map resolution used. The use of more detailed source data and map resolution may improve the final result.

Improvement of the method of combined plans for the analysis of channel re-formations of a water body on the example of the oka river section

The article discusses the ways of improving the method of combined plans for a water body channel reformations analysis on the example of a section of the Oka River. The main disadvantages of the existing classical approach to the analysis of channel processes through the channel surveys separate isobaths’combination are highlighted. A new approach to combining digital models of the river bed relief obtained from the hydrographic surveys results is proposed. Two directions of surface comparison are shown for the subsequent analysis of channel processes. For a qualitative assessment of channel changes, it is proposed to construct a new surface of vertical deformations and visualize it in color gradation or using lines of equal vertical deformations. For a quantitative assessment of channel processes, the use of a cartogram of vertical channel deformations is considered, and the numerical parameters for assessing the stability of the river channel are introduced. For the considered section of the Oka river channel, the main indicators of channel processes were obtained and analyzed using the proposed updated method. Separately, the calculation of the most optimal grid size was performed when constructing a cartogram of vertical channel deformations.

Sublacustrine canyons of the South and Central Basins of Lake Baikal as a result of interaction of tectonic, lithological and climatic factors

To study the morphological characteristics of the largest canyons in the Southern and Central Basins of Lake Baikal, we analysed a digital relief model based on high-resolution multibeam bathymetric surveying. We evaluate the role of tectonic, lithological and climatic controlling factors in the formation and evolution of canyons. Tectonic activity and seismicity act as a catalyst for canyon formation and for the development of sublacustrine gravity flows and turbidity currents, and alter the morphological appearance of already existing canyons. The influence of tectonics on the formation of the Baikal canyons is particularly noticeable on the western slope of Lake Baikal, where canyons are mainly located along faults and follow their directions. Gravity flows and turbidity currents become more important during earthquakes and periods of lower lake level. When canyon heads are located close to river mouths, riverine processes have a significant impact on the evolution of the canyon. The topography of the original surface and the lithology of the substrate also play a significant role in the evolution of canyons and in shaping the canyon morphology. During periods of lower lake level (during Pleistocene glacial periods) riverine processes were responsible for initiating the formation of many canyons in Lake Baikal. The canyons developed under the complex influence of the factors considered. One or another factor could be dominant at different stages of their evolution, while the role of the other factors became secondary. These roles could interchange over time. The Baikal canyons show a great deal of resemblance to canyons in marine environments, in terms of morphological characteristics as well as of canyon-forming processes. We propose a morphogenetic classification of the underwater valleys and canyons of Lake Baikal.

Gradient fill fairway plotting method for mapping inland waterways

This article proposes a method for plotting fairways using gradient fill of digital terrain models of the bottom relief. The purpose of the method is to improve the accuracy of fairway plotting, ensuring the safety of both manned and unmanned navigation. Non-regulated fairways are usually plotted by eye. When done this way, the accuracy of the fairway placement directly depends on the cartographer’s capability and initial data. Gradient fill allows the operator to instantly and accurately assess bottom relief, without having to analyse text. Gradient fill is used to fill a digital terrain model of the bottom relief built based on an irregular depth grid densified via the biquadratic spline interpolation.

Early assessment of seismic hazard in terms of Voronezh massif-Moscow Depression contact

Purpose is to develop a system approach for early assessment of areas being of high seismic hazard and characterizing by low stability of rock mass relative to external loads. Methods. Well cores have been assessed down to 30 depth and seismic observations have been accumulated. Complexes of field geophysics methods have been applied for the research as well as remote sensing materials, digital model of surface relief, and techniques of qualitative and quantitative interpretation. Findings. Seismic hazard map has been formed in terms of seismic intensification and ground displacement units. The abovementioned is quite reliable but a cost-based result involving early assessments of high seismic hazard areas to infill network of geophysical measurements in the neighbourhood of the areas for their further quantitative characterization. It has been identified that rare well network and definite geophysical lines, run under conditions of a complex terrain, cannot localize the areas of high seismic hazard to focus builders on the enforcement of certain components of the erected structures. It has been defined that end result of the prognostic developments takes a shape of mapping of local areas with the decreased stability of upper share of the geological section supported by further measurements by means of a common depth point method (CDP). Comparison of potential secondary earthquake sources with high permeability zones makes it possible to predict highly reliable areas of the increased seismic magnitude. Originality.For the first time, interpretation techniques have been adapted to describe parametrically nonpotential geofields (i.e. optical density of remote basis; and relative elevation), accepted during the steps of potential field processing, with the use of wave analogies. Practical implications.The methods have been developed helping optimize field geological and geophysical operations in terms of area and well number as well as measuring stakes under the conditions of the limited prior data amount.

A three-dimensional thermohydrodynamic model for Krasnoyarsk Reservoir

The paper presents a 3D model for a deep flowing water body based on the open software package Delft3D to describe and predict thermohydrodynamic (THD) processes in existing and projected reservoirs of Siberia. As an example, a 3D model for non-stationary THD processes of the Krasnoyarsk Reservoir was built and tested. For its construction, we developed a Digital Relief Model (DRM) for the Krasnoyarsk Reservoir basin, generated a finite-difference grid, identified the empirical constants and formulated the initial and boundary conditions. Numerical simulation of current velocity and water temperature of the reservoir for spring/summer of the scenario year was performed.

ГЕОДЕЗІЯ, КАРТОГРАФІЯ І АЕРОФОТОЗНІМАННЯ

Aim of the work. To develop a method of automated allocation of catchment basins and obtaining their hydrological and morphometric characteristics, which is based on digital terrain models. Methods and results of work. A necessary condition for the correct filling of the terrain is the presence of points of true flow at the edge of the settlement area (if the river flows into the lake, it should not enter the calculated area completely, otherwise incorrect results will be obtained). By performing the operation of filling the relief of the terrain, a new dem is created, which does not contain fictitious depressions and is used in the next step as input data to calculate the flow direction according to the algorithm d8. According to the proposed technological scheme it is necessary to process step by step the following six blocks: filling of closed depressions, calculation of runoff direction, calculation of total runoff, creation of point vector data set of closing points (mouth points), creation of watershed boundaries, raster-vector data conversion. Theoretical research tested the method of automated allocation of watersheds, namely the determination of hydrological and morphometric parameters of the terrain. The pools were ranked according to these parameters according to the existing classifications, a series of relevant thematic electronic maps was compiled. It should be noted that in Skole district of lviv region there are 590 catchment areas, and their area is 1407 km2. Watersheds are classified by outcrop, namely low-mountain basins in the region of 6, their area is 7 km2, medium-mountain 360, area 755 km2, high-mountain 224, area 645 km2. Pools are classified according to the average slope: the first category from 0-3 degrees, very gentle slopes - pools 27, area 7 km2; the second category from 9-12 degrees, sloping slopes-pools of 128, the area 303 km2; the third category from 12-15> degrees, steep slopes - pools of 225, the area 648 km2. The accuracy between the reference and the original relief model was evaluated. We can say that sle = 0.63 (m) slope, sle = 5.43 (m) height. Scientific novelty and practical significance. The technological scheme of automated separation of catchment basins according to digital relief models for Skoliv district of lviv region is proposed and the method of separation of catchment basins is worked out. According to the developed method, maps of watercourses of different orders and their catchment basins and classification of basins by area on the territory of Skole administrative district, which can be used by local organizations on water resources, are constructed.