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1:10000 scale mapping with GPS and free GIS tools - comparison with topographic map
11-21Views:76Reliability 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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Remnant surfaces in the Tárkány Basin
20-30Views:215The terraces of the Tárkány Basin, located in the SW part of the Bükk Mountains are known since the beginning of the 20th century. Based on field surveys, six morphological levels were delineated and described in 1936. During the later geological mapping surveys, three gravel terraces had been mapped in the basin. Since then, no comprehensive morphological mapping has been made in the Tárkány Basin. Our study aimed to validate the results of these early studies using a digital elevation model. We delineated the remnant surfaces of the basin by morphometric and GIS techniques. Then, based on field surveys and former geological maps; we characterised these remnant surfaces, and their area was measured as well. The results of this study contribute to a better understanding of the surface evolution of the basin and its surroundings.
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Mapping of river waterquality using inverse distance weighted interpolation in Ogun-Osun river basin, Nigeria
48-62Views:784Sustainable management of water resources involves inventory, conservation, efficient utilization, and quality management. Although, activities relating to quantity assessment and management in terms of river discharge and water resources planning are given attention at the basin level, water quality assessment are still being done at specific locations of major concern. The use of Geographical Information System (GIS) based water quality information system and spatial analysis with Inverse Distance Weighted interpolation enabled the mapping of water quality indicators in Ogun and Ona catchment of Ogun-Osun River Basin, Nigeria. Using 27 established gauging stations as sampling locations, water quality indicators were monitored over 12 months covering full hydrological season. Maps of seasonal variations in 10 water quality indicators as impacted by land-use types were produced. This ensured that trends of specific water quality indicator and diffuse pollution characteristics across the basin were better presented with the variations shown along the river courses than the traditional line graphs. The production of water quality maps will improve monitoring, enforcement of standards and regulations towards better pollution management and control. This strategy holds great potential for real time monitoring of water quality in the basin with adequate instrumentation.
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Spatial distribution of selected soil features in Hajdú-Bihar county represented by digital soil maps
203-213Views:257With the ongoing DOSoReMI.hu project we aimed to significantly extend the potential, how soil information requirements could be satisfied in Hungary. We started to compile digital soil maps, which fulfil optimally general as well as specific national and international demands from the aspect of thematic, spatial and temporal accuracy. In addition to relevant and available auxiliary, spatial data themes related to soil forming factors and/or to indicative environmental elements we heavily lean on the various national soil databases. The set of the applied digital soil mapping techniques is gradually broadened. In our paper we present some results in the form of brand new soil maps focusing on the territory of Hajdú-Bihar county.
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Landslide Susceptibility mapping using the Analytical Hierarchy Process and GIS for Idukki District, Kerala, India
11-32Views:154This study demonstrates the application of the analytical hierarchy process (AHP) technique for landslide susceptibility mapping of Udumbanchola and Devikulam taluk of Idukki district (Kerala, India). The landslide conditioning factors, such as lithology, geomorphology, slope angle, slope aspect, relative relief, drainage properties, land use/ land cover, and lineament characteristics,are derived using remote sensing data and GIS. The landslide susceptibility of the region is estimated using the weights derived by the AHP method. The analysis indicates the controls exerted by the structural and fluvial process and relief characteristics on the landslide activity of the region. The landslide susceptibility map of the region suggests that the high and severe susceptible zones cover about 10.68% of the area, and another 9.40% falls under the moderate susceptibility zone. The results highlight the significance of implementing various structural and non-structural measures in the moderate to severe susceptibility zones to mitigate the impacts of landslides.
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Mapping aquatic vegetation of the Rakamaz-Tiszanagyfalui Nagy-Morotva using hyperspectral imagery
1-10Views:190Rapid development in remote sensing technologies provides more and more reliable methods for environmental assessment. For most wetlands, it is difficult to walk-in without disturbing the endangered species living there; therefore, application of opportunities provided by remote sensing has a great importance in population-mapping. One effective tool of vegetation pattern estimation is hyperspectral remote sensing, which can be used for association and species level mapping as well, due to high ground resolution. The Rakamaz-Tiszanagyfalui Nagy-morotva is an oxbow lake, located in the north-eastern part of Hungary. For this study, a wetland area of 1.17 km2 containing the original water bad and shoreline was selected. For the image analysis, images taken by an AISA DUAL system hyperspectral sensor were used. At the same time, 7 main vegetation classes were separated, which are typical for the sample plot designated on the test site. Classification was performed by the master areas signed by the most common associations of the Rakamaz-Tiszanagyfalui Nagy-morotva with determined spectrums. During the image analysis, SAM classification method was used, where radian values were optimized by the results of classification performed at the control area.
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The developement of red mud flood environmental information system and the methodology for the spatial analysis of the degraded area
1-11Views:218The red mud disaster occurred on 4th October 2010 in Hungary has raised the necessity of rapid intervention and drew attention to the long-term monitoring of such threat. Both the condition assessment and the change monitoring indispensably required the prompt and detailed spatial survey of the impact area. It was conducted by several research groups - independently - with different recent surveying methods. The high spatial resolution multispectral aerial photogrammetry is the spatially detailed (high resolution) and accurate type of remote sensing. The hyperspectral remote sensing provides more information about material quality of pollutants, with less spatial details and lower spatial accuracy, while LIDAR ensures the three-dimensional shape and terrain models. The article focuses on the high spatial resolution, multispectral electrooptical method and the evaluation methodology of the deriving high spatial resolution ortho image map, presenting the derived environmental information database.
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Accumulation studies at specific sampling areas of the active floodplain in the Upper-Tisza region
14-22Views:216In this paper the rate of accumulation was studied along four VO floodplain cross sections of the UpperTisza region between 1974 and 2014. VO floodplain cross sections are based on a mapping base-point grid (established in 1890), and they are located a few kilometers from each other. Furthermore, the roughness changes of different surface types, crossed by the VO floodplain cross-sections, were also determined between 1965 and 2015. The accumulation studies were extended to include the accumulation rates of the cut off meanders located along and/or close to the VO cross-sections. The roughness values increased in all four floodplain VO cross-sections since 1965; in two of them it reached or approximated 100 %. The average accumulation along the VO cross-sections was between 28 and 47 cm (0.73–1.23 cm/year) during the 38-year period. However, its areal distribution showed large differences. The highest values (169–309 cm, i.e. 4.44–8.13 cm/year) were found at the lowest points of the cut off meanders and swales in every case. The accumulation rate of the examined three cut off meanders near the floodplain cross-sections (140 and 1570 meters from the river bed) was lower (0.84–2.5 cm/year), but the study period was significantly longer (154 and 161 years, respectively). Comparing the values of the two periods, it is obvious that the accumulation of the active floodplain accelerates, presumably due to the significant increase of surface roughness.
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Wind damage on trees following hurricane Sandy and implications for city landscaping: Glen Ridge - Montclair towns, New Jersey
1-11Views:92Glen Ridge is a small municipality in the Northern New Jersey with a significant number of huge trees lining majority of its streets. The trees have been subject to a wide range of natural and artificial stresses, one being the strong wind associated with superstorm Sandy. On 29th October 2012, a windstorm of extreme intensity struck the Tristate region and brought havoc to the tree population including those in Glen Ridge. A survey was conducted immediately after the storm to collect quantitative information on fallen tree population. The study aimed at understanding the spatial extent of wind damage on trees with reference to location, trunk diameter and soil characteristics. A total of 51 fallen trees with a mean trunk diameter of 100.4 centimetres along streets in study area were surveyed. High damage was noted on trees in Glen Ridge (29 trees) while streets transitioning to Montclair had 22 fallen trees. Majority of the surveyed trees were found on USBOO soils (49%), which are characterised as disturbed urban soils with Boonton substratum-Boonton complexes. BowrB soils had 27.5%, Boob 13.7%, BowrC 7.8% and USDUNB 2.0% of fallen trees. A need for city wide tree inventorying and species mapping is identified as a management implication to further enhance the historical value of the city. Other measures are discussed with a view of engaging appropriate local management partnerships and coordination frameworks to play a role in protecting the remaining large trees.
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Specific features of NDVI, NDWI and MNDWI as reflected in land cover categories
194-202Views:1188The remote sensing techniques provide a great possibility to analyze the environmental processes in local or global scale. Landsat images with their 30 m resolution are suitable among others for landcover mapping and change monitoring. In this study three spectral indices (NDVI, NDWI, MNDWI) were investigated from the aspect of land cover types: water body (W); plough land (PL); forest (F); vineyard (V); grassland (GL) and built-up areas (BU) using Landsat-7 ETM+ data. The range, the dissimilarities and the correlation of spectral indices were examined. In BU – GL – F categories similar NDVI values were calculated, but the other land cover types differed significantly. The water related indices (NDWI, MNDWI) were more effective (especially the MNDWI) to enhance water features, but the values of other categories ranged from narrower interval. Weak correlation were found among the indices due to the differences caused by the water land cover class. Statistically, most land cover types differed from each other, but in several cases similarities can be found when delineating vegetation with various water content. MNDWI was found as the most effective in highlighting water bodies.
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Correction of Atmospheric Haze of IRS-1C LISS-III Multispectral Satellite Imagery: An Empirical and Semi-Empirical Based Approach
63-74Views:275The atmospheric effect greatly affects the quality of satellite data and mostly found in the polluted urban area in the great extent. In this paper, the atmospheric correction has been carried out on IRS-1C LISS-III multispectral satellite image for efficient results for the Raipur city, India. The atmospheric conditions during satellite data acquisition was very clear hence very clear relative scattering model of improved dark object subtraction method for the correction of atmospheric effects in the data has been carried out to produce the realistic results. The haze values (HV) for green band (band 2), red band (band 3), NIR band (band 4) and SWIR (band 5) are 79, 53, 54 and 124, respectively; were used for the corrections of haze effects using simple dark object subtraction method (SDOS). But the final predicted haze value (FPHV) for these bands are 79, 49.85, 21.31 and 0.13 that were used for the corrections of haze effects applying improved dark object subtraction method (IDOS). We found that IDOS method produces very realistic results when compared with SDOS method for urban land use mapping and change detection analysis. Consequently, ATCOR2 model provides better results when compared with SDOS and IDOS in the study.
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Remote Sensing and GIS based site suitability analysis for tourism development in Vaishali block, Bihar, India
12-22Views:590Geographic Information Systems (GIS) and Remote Sensing are presently recognized generally as an improve instrument for overseeing, breaking down, and showing gigantic volumes of fluctuated information suitable to numerous neighborhood and provincial arranging exercises. Because of the composite idea of the travel industry arranging issues, the planned of GIS in settling these issues is progressively perceived. This paper will think a portion of the conceivable outcomes of GIS applications in the travel industry arranging. For the most part, GIS applications in the travel industry have been tight to recreational office stock, the travel industry situated land the board, and diversion untamed life strife; and have been thin by absence of financing, and awkward techniques. Utilizing the case of site wellness investigation for the travel industry improvement and mapping, this paper features a few uses of GIS in the travel industry arranging in vaishali square, Bihar. According to our present investigation; the most reasonable the travel industry site recognized by the examination is inside significant towns. The urban focus with plausibility to develop into the travel industry focuses. The rest of the land shows a low appropriateness scale because of absence of significant appreciation for make a solid force factor. Availability is an essential for the travel industry advancement. Great street organize availability with closeness to railroads station or air terminal demonstrated solid vacationer potential site, this combined with proximity to grand magnificence delineates high appropriateness. Significant vacation destinations, for example, legacy locales, gardens and water bodies or lake demonstrated high appropriateness. This can be corresponded to the way that legacy destinations and other high appropriate highlights are converted into reasonable the travel industry site.
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Evaluation of the possibilities for stream restoration: preassessment of the Váli-stream (Hungary)
26-44Views:240The purpose of this study is to evaluate the potential of restoration of a stream section. The starting point of the multiple-step assessment process was a historical analysis, which resulted in the definition of different sections within the study area, providing a base for the further restoration goals. The assessment of the current conditions was elaborated particularly to determine those factors, which could limit restoration. These assessments cover the land use pattern, furthermore the analysis of vegetation and habitat patches. As a result of the historical analysis, it has been found that the stream side habitat patches have decreased significantly despite the constant space available. This change was not caused by the increased area of the settlement, but rather by the higher dominancy of arable forms of land use. The greatest share of wet and mesic meadows and agricultural habitats in the study areas, covering 57.5% of the total area, indicates significant anthropogenic effects. Consequently it can be stated that the reference conditions are not the only determining factors of the restoration possibilities. Restoration style and intensity have been defined on basis of all assessed factors.
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A historic geographic approach to the anthropic disturbance in the Bükk region
58-65Views:308This paper introduce a historical geographical study on the process of land cover transformation in the Bükk Region, which can be regarded as a two-faced area concerning its anthropogenic disturbance. Based on historic mapping that began as early as the late 18th century, a database was produced, and the data was interpreted in the context of economic and social processes that took place in the area. Results could be presented in maps using the so-called Anthropogenic Disturbance Index (ADI). These maps demonstrate the peculiar land use pattern in the Bükk Region, namely co-habitation of the significantly transformed margins and the natural or quasi-natural central part. Between them, there are linear areas of intermediate disturbance. These areas, however, due to the foundation and activity of the Bükk National Park and modification of their economic value after the change of the political system, have not increased during the last several decades; rather a re-naturalization of the landscape is aimed.