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Analysis of multitemporal aerial images for fenyőfő Forest change detection
89-100Views:223This study evaluated the use of 40 cm spatial resolution aerial images for individual tree crown delineation, forest type classification, health estimation and clear-cut area detection in Fenyőfő forest reserves in 2012 and 2015 years. Region growing algorithm was used for segmentation of individual tree crowns. Forest type (coniferous/deciduous trees) were distinguished based on the orthomosaic images and segments. Research also investigated the height of individual trees, clear-cut areas and cut crowns between 2012 and 2015 years using Canopy Height Models. Results of the research were examined based on the field measurement data. According to our results, we achieved 75.2% accuracy in individual tree crown delineation. Heights of tree crowns have been calculated with 88.5% accuracy. This study had promising result in clear cut area and individual cut crown detection. Overall accuracy of classification was 77.2%, analysis showed that coniferous tree type classification was very accurate, but deciduous tree classification had a lot of omission errors. Based on the results and analysis, general information about forest health conditions has been presented. Finally, strengths and limitations of the research were discussed and recommendations were given for further research.
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Studying the accuracy of orthophotos on the example of various terrain models in study areas in Hungary
31-39Views:135Depending on the orientation data, the accuracy of the applied terrain models and the field content of the orthophotos data of different accuracy can be obtained in the course of analysing orthophotos. Considering the factors influencing accuracy, differences resulted by the application of different elevation models are studied in this paper in two study areas in Hungary. Primary aim of this study is to determine the magnitude of differences between the co-ordinates of reference points digitized from orthophotos and that of points measure.
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Remnant surfaces in the Tárkány Basin
20-30Views:196The 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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Protected areas in regions of intensive economical activity: conflict of nature protection and nature use (case study of Dovine river catchment)
43-56Views:62Nature protection and economical activity clash of interests is analysed on the example of Dovinė River catchment, situated in the south western part of Lithuania. It is a unique wetland complex consisting from Žuvintas Lake and the surrounding bogs (Fig. 1). Žuvintas Lake became the first protected area in Lithuania in 1937. However, the lake is situated in one of the most fertile region of Lithuania, where the methods of intensive farming activity is being employed for a long time. Eutrophication processes and overgrowth of this shallow lake has been very active during the several decades and the lake has lost its ecological value. Therefore the main goal of this article is to analyse the anthropogenic influence towards the water bodies and protected natural values situated in the territory of intensive economical activity. Cartographical material of different periods is being used for the evaluation of the hydrographical network transformations in Dovinė River catchment. Hydrochemical parameters of the periods 1953–1954, 1960–1961, 1980–1982; 1993–2003; 2004–2005 of the water bodies in Dovinė River catchment are being analysed. The field works in order to investigate the water quality in Dovinė River and it‘s tributaries were made in spring of 2005. Water samples were analysed in laboratory of the Institute of Geology and Geography according water quality analysis methods approved by Lithuanian Ministry of Environment (Table 2). Water quality was evaluated according maximum residue limits (MRL) in surface waters (Table 3). The results of the study showed that although Žuvintas Lake is being protected for 70 years, the farming activity intensified constantly in its catchment. Canalised river beds and sluice–regulated hydrological regime of the lakes diminished the natural self–cleaning abilities of the water system. The average annual decrease of the lake specular surface was about 1,1 ha in the period of 1961–2003. The average annual increase of vegetation area is about 0,14 ha. Even a strong protection regime did not preserve this territory. Therefore, in order to keep the sustainable development in the protected territories the anthropogenic loading from the neighbouring territories (catchment area, etc) must be evaluated. The objectives of nature protection in protected territory could not be attained if there is no regulation of economical activity in the territories surrounding the protected area.
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Case study for estimation of the amount of contaminants stored in soil in an industrial area
1-11Views:263One of the main sources of contaminants in the soil is industrial activity which has become one of the major environmental problems of the last few decades. The development of geoinformatics as well as the introduction of standards and regulations has led to a decreased risk of soil contamination and the cost-effective optimization of remediation activities. Based on the above, the aim of our study is to demonstrate the geoinformation processing of the remediation performed in an industrial area located in the Great Hungarian Plain, with special regard to the estimation of the amount and spread of the contaminants accumulated in the soil. In order to reveal the lithological and hydrogeological properties of the investigated area and the environmental status of the underground areas, we performed a large number of shallow land drillings (115). During the field sampling, 1000–1500 grams of samples were collected from the drill bit and were processed in an accredited laboratory. Based on the concentration and volume models created it can be concluded that with the estimations performed via modeling, we were able to locate the most critical areas from the standpoint of contamination. It was revealed that the focal point of the contaminants accumulated in the soil was in the central part of the investigated area. Furthermore, the model demonstrated the effect of lithological factors, since contaminants tend to accumulate more heavily in cohesive soils compared to porous rocks. The extent of contaminant concentration in the aquifer increased with decreasing depth; however, after reaching the floor clay the extent of contaminant concentration began to decrease. The lithological layer closest to the surface contained the most contaminants.
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Comparison of soil moisture indices and field measurements in hilly agricultural lands of SW Hungary
50-57Views:251The retention of surface runoff and the preservation of soil moisture are among the most important water-related ecosystem services. In addition to field monitoring, advanced remote sensing techniques have been devised to reveal soil moisture dynamics on agricultural land. In our study we compare two soil moisture indices, TWI and SAVI, in three agricultural areas with different land use types. The SAVI has been found suitable to point out spatial variation on the moisture conditions of the vadose zone.
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Interpolation and 3D visualization of soil moisture
23-34Views:359Adaptation to climate change demands the optimal and sustainable water management in agriculture, with an inevitable focus on soil moisture conditions. In the current study we developed an ArcGIS 10.4. platform-based application (software) to model spatial and temporal changes in soil moisture in a soy field. Six SENTEK Drill & Drop soil moisture sensors were deployed in an experimental field of 4.3 hectares by the contribution of Elcom Ltd. Soil moisture measurement at each location were taken at six depths (5, 15, 25, 35, 45 and 55 cm) in 60-minute intervals. The model is capable to spatially interpolate monitored soil moisture using the technique. The time sequence change of soil moistures can be tracked by a Time Slider for both the 2D and 3D visualization. Soil moisture temporal changes can be visualized in either daily or hourly time intervals, and can be shown as a motion figure. Horizon average, maximum and minimum values of soil moisture data can be identified with the builtin tool of ArcGIS. Soil moisture spatial distribution can be obtained and plotted at any cross sections, whereas an alarm function has also been developed for tension values of 250, 1,000 and 1,500 kPa.
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Estimating soil loss from a watershed in Western Deccan, India, using Revised Universal Soil Loss Equation
13-25Views:346USLE (Universal Soil Loss Equation) is the original and the most widely accepted soil loss estimation technique till date which has evolved from a design tool for conservation planning to a research methodology all across the globe. The equation has been revised and modified over the years and became a foundation for several new soil loss models developed all around the world. The equation has been revised as RUSLE by Renard et al. (1991) and is computed in GIS environment. The Revised equation is landuse independent which makes it a useful technique to apply in a variety of environment. The present paper is an attempt to estimate soil loss from a semi-arid watershed in Western Deccan, India by employing RUSLE. The region is a rocky terrain and sediments are restricted to only a few localities. The result indicates that the region is at the threshold of soil tolerance limit.
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Morphology, sedimentology and origin of an anomalous cut-off along the Pravara river, deccan trap region, India
23-43Views:261River meanders have always been an intriguing subject in fluvial geomorphology because of their ubiquity, dynamism, remarkable forms and practical consequences of their movement. Sometimes a relatively straight channel flowing over bedrock may develop a lone meander bend cut-off which is very out of the place from the surrounding area. The occurrence of a sudden bend along a river may not be a meandering bend but may be manifestation of sudden change in the river dynamism due to many reasons, such as, lithology, change in rainfall regime, tectonics etc. The formation of such features highlights the behavior of river in the past. One such striking feature has been observed along the River Pravara in the Deccan Trap Region, Maharashtra, India. Rivers in Deccan Trap Region do not meander and form cut-offs by rule. It is rocky country where rivers flow in deeply incised bedrock. Hence, the observed feature displays a striking anomaly in this region. Hence, an attempt has been made in the present paper to evaluate the mode of formation of this single cut-off along this channel. Morphological and sedimentological data were generated and analyzed for the channel loop and the link channel to understand the competence of the river in the past and present which were directly or indirectly responsible for the development of this channel anomaly in this reach. Based on the results of the analysis and intensive field observations, it has been inferred that this is a classic example of natural morphological adjustment of a river when a set of events occurred, first retardation of vertical erosion encountering bedrock followed by series of floods to induce the channel to divert from the original path to resume the present course. Presence of a tributary further aided to the process of the loop development. The study can provide additional knowledge to the studies involving anomalous channel cut-offs at any part of the world.
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Studying the development of fluvial landforms in the Berettyó-Körös Region using geoinformatic methods
137-144Views:158Development of fluvial landforms from 1980 till nowadays was studied based on digital elevation maps (DEM) composed from contour lines of topographic maps, field data obtained by RTK GPS and aerial photos taken by a drone. Greatest denudation of 6-9 metres was measured in the eastern side of the erosional valley at Pocsaj caused by piping and mass movements. As a result, the valley widened and slightly deepened. Since 1980 around 1-2 metres of accumulation and erosion of similar rate have been measured in the secured floodplain environment dissected by abandoned beds, point-bars and swales at Kismarja. These values, however, rather reflect the geometric uncertainties and deficiencies of the contours of topographic maps than real land changes. Therefore topographic maps can give reliable basis for studying the development of lowland landforms only if they depict adequately large sized (minimum 100 x 100 m) positive or negative forms with great height difference as well (minimum 8-10 m). Accuracy of DEMs composed from aerial photos using photogrammetric methods – taking off height faults caused by vegetation – is around the same as that of the models created on the basis of RTK GPS measurements.
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The appearance of renewable energy sources in the settlement development documents of local authorities in Jász-Nagykun-Szolnok County
42-49Views:127In recent decades, several new trends can be observed in the field of energy management, one of which is the increase of the role of renewable energy sources. As a result of this fact, local authorities in Hungary have also devoted increasing attention to this question in recent years. The first step of their interventions is the drawing up of the appropriate development documents, relying on which specific steps/investments can also take place later. In the spirit of the above, the objective of the present paper is to analyse the development documents of local authorities in Jász-Nagykun-Szolnok County. The most important findings of the study could be summarised as follows. Firstly the Integrated Settlement Development Strategies prepared for the period 2014 to 2020 dealt with the topic of renewable energy sources in much more detail than earlier documents. Secondly from the various renewable energy sources, the development document devoted most attention to solar and geothermal energy and thirdly the appearance of renewable energy sources in the development documents shows a close link with the size of the settlements.
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Biogeomorphological feedback in karst areas
101-108Views:206In the last decades, the research on ecosystem services have emerged in the field of geography. The negative impacts of human activities on the vulnerable karst areas are getting enforced quickly, which have an unfavourable influence on ecosystem service provision. On karstic areas, there are significant geographical processes, connected to biological activities. This issue is not adequately discussed in the current literature of karst ecology. In our study, we give an overview on the biogeomorphological feedbacks that change the functions and overall value of karst ecosystems.