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1:10000 scale mapping with GPS and free GIS tools - comparison with topographic map
11-21Views:133Reliability of the road system illustrated on topographic maps with 1:10000 scale is questionable due to their age, but surveying a territory with area over 100 hectares is expensive with classical geodetic tools, although there is no need of geodetic accuracy in most cases. GPS-based mapping method described in this paper is suitable in these situations. The main concept is to keep the costs of the survey as low as possible, therefore free GIS applications and databases were used with navigation purpose GPS receivers. The accuracy provided by these devices is good enough for those purposes where the accuracy of topographic map with 1:10000 scale is adequate. GPS-based mapping can be done to update the road system of existing map or create own detailed road databases. The result of the work is not just a database but a navigation capable digital map, which can aid further activities on the field, like geographic researches, environment protection, tourism, fire service etc.
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Transformation of land use pattern in the East Borsod coal basin from the beginning of minig industry to the political changes
223-231Views:363Historical geographic studies on land cover may support the understanding of the recent state. Focusing on coal mining, this process was followed and analyzed in the case of the East Borsod Coal Basin from the early 20th century to the political change. The contemporaneous maps and manuscripts concerning the mining were evaluated using geoinformatic techniques. Moreover, digitalized topographic map coming from the early and late period of mining (1924 and 1989, respectively) were analyzed. To determine the degree of human disturbance hemerobic relations and changes of the given land cover patches were quantified on the basis of the maps of the three military surveys, too. It can be stated that montanogenic subtype of an industrialagricultural landscape has been formed in the Bükkhát area. Beside the concentrated artificial surfaces, however, relative dominance of forest forming the matrix of the landscape remained.
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Prioritizing Watersheds for Flood Risk Assessment in Uttarakhand Himalayas using Geospatial Techniques and TOPSIS Method
54-71Views:28Uttarakhand has a highly diverse topography, with snow-covered peaks, deep canyons, roaring streams, and dusty plains, all drained by various rivers of the Ganges system, India. The present study prioritizes watersheds in the Uttarakhand Himalayas for flood susceptibility using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method, supported by GIS and remote sensing data. ALOS PALSAR Digital Elevation Model (DEM) with 12.5-meter resolution was utilized to map topographic features and to analyze 18 morphometric parameters of 28 watersheds. The TOPSIS method prioritized sub-watersheds using AHP criteria weights, which are classified into five priority levels ranging from very low to very high. The Sarju, Ram Ganga, and Song watersheds were identified as having the highest flood risk, placing them in the “Very High” priority class. These watersheds exhibited high drainage density (Dd), stream frequency (Fs), and bifurcation ratio (Rb), indicating a dense and complex drainage network prone to rapid runoff and increased flood potential. The watersheds such as Bandagarh, Parry, and Chandra Bhaga were placed in the “Very Low” priority class due to lower closeness coefficient (Cci) values, suggesting simpler drainage systems and reduced flood risk. The AUC (Area Under Curve) value of 0.789, indicates a good predictive accuracy for the TOPSIS model. The classification helps in pinpointing high-risk areas that require urgent flood management interventions.