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0UTK 528.8; 504.062
METHODOLOGY OF PROCESSING DATA OBTAINED FROM SATELLITE IMAGES IN ARCGIS SOFTWARE FOR CREATING SOIL-EROSION DIGITAL MAPS
TEYMUR AKIF HAJIYEV BALAKHANIM ARIF AGARZAYEVA NARMIN ULVI ALEKBEROVA GUNEL KIRAM AHMADOVA AMINA MASTAN HUSEYNOVA MEHRIBAN VILAYAT ZEYNALOVA NASA Institute of Ecology
Annotation. One of the most urgent problems today is the protection of the local ecosystem. The negative effects of global climate changes and natural disasters on the environment are constantly increasing. Against the background of natural and anthropogenic effects on soils formed in accordance with the law of vertical zonation in altitude zones, the failure to study the ecosystem impact process on the nature and biological diversity of these areas as a whole has led to consequences resulting in soil degradation. In addition to spatial surveys, data obtained from satellite images is also widely used, which is considered one of the main methods for determining environmental damage.
Key words: digital map, raster image, soil erosion, degradation, remote sensing, cartographic
basis
РЕЗЮМЕ НА СТАТЬЮ "МЕТОДИКА ОБРАБОТКИ ДАННЫХ СПУТНИКОВЫХ СНИМКОВ В ПРОГРАММЕ ARCGIS ДЛЯ СОЗДАНИЯ ЦИФРОВЫХ КАРТ ЭРОЗИИ ПОЧВ"
Аннотация. В статье рассматриваются принципы и методология разработки цифровых карт на основе данных дистанционного зондирования Земли и технологии ArcGIS разрушения и деградации природных экосистем, сформировавшихся на Большом Кавказе под природным и антропогенным воздействием.
Ключевые слова: цифровая карта, растровое изображение, эрозия почвы, деградация, дистанционное зондирование, картографическая основа
Introduction. Climate is one of the active natural factors and plays a driving role in the process of soil formation. Climate characteristics mainly predetermine the probability of soil erosion and are considered to be the main natural factors in determining its development as well as the intensity of soil flow. changes, erosion and degradation processes have caused environmental problems, which made it necessary to study them, as well as to analyze the changes and create a description on the maps. The main source of information in the creation of soil-erosion maps is cartographic materials. These materials mainly include topographical, thematic maps and space images. Satellite images are widely used in the preparation of soil-erosion maps. Satellite imagery combines multi-channel spectral zonal imagery. In addition, the information provision of soil erosion maps includes literature survey and statistical sources.
Research object and methodology. The lands of Kabala and Balakan regions, located in the Greater Caucasus physical-geographical region, were taken as an example of the research object. Digital maps were prepared by entering the mathematical data obtained as a result of ground measurements and decoding of space images during the soil survey into the database using the Arc GIS software.
Analysis of the results. Cartographic maps from 1985 were used to compare the land cover of Kabala and Balakan regions. So, several maps belonging to the research area were first brought to the
ОФ "Международный научно-исследовательский центр "Endless Light in Science"
coordinates using the tools in the "Georeferencing" menu, and then the map brought to the coordinates using the "Clip" tool located in the "Data management tools" menu in the "Toolbox" was cut according to the area of the research area. In the end, the land cover area of Kabala and Balakan districts was extracted and digitized from these maps through vectorization. The areas of land cover in Kabala and Balakan regions were calculated using "Open Attribute Table" from the received digital maps. Soil-erosion maps are drawn up mainly in 2 directions: maps of eroded soil; soil maps protected from erosion [1].
The multifaceted nature of soil erosion problems requires the application of various methods and techniques. Cartographic research methods are especially important among these methods [2]. Because with these methods, in addition to the compilation of maps and atlases, the synthesis of knowledge reflecting the interactions between nature and society is studied. The main stages used in the preparation of soil-erosion maps are as follows:
- Detection of eroded areas and determination of their contours;
- Landscape ecological decoding of space images and creation of topographic bases;
- Selection of conventional signs to describe the objects on the map where the soil erosion process is taking place;
- Preparation of the legend and the initial version of the maps;
- Detection of eroded soils based on space images, determination of their classification and characteristics.
The map was created by applying GIS technologies based on the ArcGIS 10.3 platform produced by ESRÍ and using modern map design methods. The appropriate cartographic network of the map is drawn, the legend, appropriate conventional signs are developed (picture 1.).
Picture 1. Land map of Kabala region
ОФ "Международный научно-исследовательский центр "Endless Light in Science"
The soil erosion map prepared on the basis of these stages is distinguished by its visibility, completeness, and abundance of geographical information. On the basis of these maps, it is possible to determine the characteristic features of soil processes, the results of the relationship between society and nature. In modern times, a new field of thematic cartography, land-ecological cartography, is being formed. The implementation of soil-ecological monitoring primarily refers to cartographic and spatial image materials. Because the cartographic and aerospace research methods and the materials obtained based on them provide extensive, regular and operational information about the dynamics of the environment and ecological conditions (Pic. 2.).
Picture 2. Land map of Balakan region Composition elements, that is, additional information, supply elements can be located inside and outside the map frame. The frame of the map, being the main compositional element, is considered one of the important mathematical elements and the border of the cartographic image. The map frame is divided into 3 parts, the main or inner frame, the minute or degree frame, and the outer frame.
In modern large and medium-scale topographic maps, the geographic image is limited directly by the inner frame. Sometimes, even on small-scale geography maps, the inner frame corresponds to the meridian and parallels. This is the case in maps made in straight cylindrical projections, maps of hemispheres, etc. happens. In some geographic maps, the internal frame lines do not correspond to meridians and parallel
Two lines are drawn parallel to the degree frame at some distance from the inner frame. The parts between meridians and parallels on the degree frame are divided into minutes on large-scale maps, and degrees on small-scale maps. Using the degree frame, you can find the geographic coordinates of a certain point on the map, or vice versa, move the point on the map according to the geographic coordinates.
At a certain distance from the degree frame, the outer frame of the map is drawn parallel to it. The numerical value of the geographic coordinate of the cartographic network is written between the edge and degree frames. Digital maps are a digital model of the earth's surface, they are prepared as a result of photogrammetric processing of data obtained as a result of remote sensing, digitization of cartographic sources, which are compatible with all types of maps both in content and scale. Digital maps are created as a result of analyzes and calculations carried out in automated cartographic systems and geographic information systems. Digital maps are also compatible with other map classifications. For example, digital soil maps, digital vegetation maps, digital cadastral maps, etc. Digital maps are prepared in the following order:
- Carrying out certain analyzes using previously prepared topographic maps of a large scale;
- Photogrammetric processing of data obtained as a result of remote sensing (raster data acquisition);
- Field measurements (for example, geodetic measurements - using electronic tachometer, GPS, etc. tools);
- Processing of points obtained in the field under camera conditions.
After all these processes are done, the map is prepared. Composition elements for the map are prepared. The composition elements of the map include the frame and the legend. Conventional signs used on the map are reflected in the legend. A coordinate grid is drawn depending on the scale. After creating digital maps, it can be converted to other programs and saved. For example, jpeg, png, tif, etc. in raster format, dwg, shp, etc. in vector format. The quality of digital maps is determined based on the following factors:
- Ability to provide information;
- Accuracy;
- Fullness;
- Having the right structure.
The reflection of all factors on a digital map depends on the accuracy of the data used for the map and the responsible approach to the work of the map engineer. Having the correct structure of the map means that it has a mathematical and geographical basis, it is drawn up in cartographic projection and scale, and it is drawn up using conventional symbols accepted in the international world [3].
A soil erosion map is a cartographic work that carries out an ecological assessment of any area. A soil map allows you to compactly display the conditions of living organisms, including the characteristics of the environment that affect the life and health of people. A complex classification of soil erosion maps includes almost all components of their most important features. According to the direction, ecological maps are divided into the following types:
- anthropocentric and bio centric;
- according to the scope of relations: specific and complex;
- according to the content: factors or circumstances, processes, situation, problems, situations, nature protection and organization of nature use;
- according to the nature of information presentation and level of analysis: inventory, estimated, predicted, recommended;
- by appointment: base and operational;
- by mapping cell: administrative unit, landscape, basin, natural economy or resource area. Complex soil-erosion maps belong to the group of geoecological maps. Geoecological maps
are compo they allow us to get a general and visual idea of the spatial data and the extent of the ecological situation as a whole. Examples of geoecological maps are soil-landscape maps reflecting the ecological situation and ecological problems [4].
The main content of the comprehensive soil erosion map is the evaluation of the modern landscape structure and environmental features important for human life. The maps created in this way characterize the spatial-temporal changes of natural conditions and life-important factors in the most complete way. Soil erosion maps drawn up in different scales and contents should first of all meet the following requirements:
a) The content of the soil erosion maps, its degree of generalization, the scope of the methods used to reflect the environmental conditions should clearly reflect the modern soil-ecological condition of the research object and complete descriptions of all ecological features that affect biota and the human body
b) Land plots, their characteristics, erosion rates described in each prepared soil erosion map must be consistent with the modern and real situation;
c) Since the same geo-geographical materials are used by specialists of different fields, the legends drawn up should be accurate, conventional signs should be clear and easy to read.
The most important task in the preparation of soil erosion maps is the creation of a uniform methodology and conventional signs. On the basis of many soil maps, derivative maps, especially ecological assessment, ecological forecast, etc., will be developed in the future. it is possible to draw maps. Soil erosion maps are a cartographic image of great importance in monitoring the environment, implementing nature protection measures, determining future directions of the country's economic development, and scientific research.
Conclusion. Thus, in the presented research, based on the data of GIS technologies and satellite images, as well as spatial data, the soils of Kabala and Balakan regions in the spring and summer of 2013 and the erosion process taking place there were determined using the comparative geographical analysis method. Topographic map and space as a result of the research conducted with the application of image data, the application and conceptual issues in the direction of preventing soil erosion were reflected, and digital maps on a scale of 1/50000 were developed and prepared.
LITERATURE
1. Solovei T. Spatial analysis using the tools of geoinformation systems. Study guide. Izd. ITP. Poland, 2012, 95 pages.
2. Yu.F. Knizhnikov, V.I. Kravtsova, O.V. Tutubalina «Aerocosmic methods of geographic studies». Moscow, 2011, p. 416
3. Mehdiyev A.S., Azizov B.M., Mehdiyev C.S. "Aerospace monitoring". Baku, "Elm" - 2005, 205 p.
4. I.V. Yakushina, N.S. Popov. "Methods and devices for environmental control". Ecological monitoring: Textbook. allowance.- Tambov. Publishing house TCTY, 2009,-188 c.
