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History of the meteorological observatoions in Debrecen
1-5Views:31Debrecen was among the first cities in Hungary where meteorological observatories were established, although the weather station of our University was put into operation 80 years ago, Meteorological observations have a much longer history in the city. In the present paper history of the meteorological observations and stations worked in the city has been reviewed with special emphasis on the meteorological observatory of the University of Debrecen.
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Heavy metal loads in the soil of Debrecen
57-67Views:41Results of examinations on the amount, and spatial distribution of heavy metal compounds in the soil of Debrecen, their geographic, pedologic and ecologic aspects are presented in this study. The effects of the differences in traffic conditions, build-up/land use and the density of vegetation on the heavy metal content of the soils have been examined in city of Debrecen and its closer environment. Cadmium-, cobalt-, nickel-, lead-, and copper-contents of the soil samples taken from 88 sites of the sample area have been studied after acidic extraction, using atomic absorption spectrometer with the flame technique. Close-to-background concentrations of heavy metals in unpolluted soils of the forested area of the Nagyerdő were determined. Spatial differences in the heavy metal content of the soils for the whole area of Debrecen have been studied. Influence of soil properties (humus, CalciumCarbonate content, pH and grain size distribution) on the binding and mobility of heavy metals in the soil has been examined. Vertical distribution and mobility of heavy metal compounds in acid sandy soils was determined. Heavy metal content of soil in the most sensitive areas, playgrounds, recreational areas, urban gardens and grazing fields along busy roads has been surveyed.
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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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Characterization of urban aerosol sources in Debrecen, Hungary
109-119Views:52Debrecen is an average middle European city from the point of view of aerosol pollution. Its location makes the city an ideal place for observing aerosol transport processes. Systematic investigation of atmospheric aerosol of the east-Hungarian region has been performed in the Institute of Nuclear Research of the Hungarian Academy of Sciences for 20 years by accelerator based elemental analytical technique. As a complementation of this research we observed the size distribution and short-term time variation of the elemental component of fine (PM2.5) and coarse (PM10-PM2.5) urban aerosol in the frame of sampling campaigns during 2007 and 2008 in a downtown site of Debrecen. Meteorological parameters were also recorded parallel to the aerosol sampling. Elemental concentrations (Z ≥ 12) were determined by particle induced X-ray emission (PIXE) analytical technique at the Laboratory of Ion Beam Applications (IBA) of the ATOMKI. On the obtained database six sources of the urban aerosol were identified: 2 types of soil, domestic heating, sulphate originating from long range transport processes, an unidentified source enriched with chlorine and traffic. Emission episodes were also observed. The short-time variation of urban aerosol combined with meteorological data and with mass size distribution serves as a basis to reach a better understanding of the aerosol sources in receptor areas, to select local emission and long range transport episodes, to follow the evolution of aerosol, and to make a better estimate on the health impact.
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A historic geographic approach to the anthropic disturbance in the Bükk region
58-65Views:288This 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.
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Cost sensitivity of international students in the largest hungarian university cities
76-84Views:225Statistics on international students distinguish between diploma mobility (full-time students abroad) and credit mobility (part-time courses, student exchanges such as Erasmus+, etc.). In terms of economic benefits, their common feature is mostly realised in the spendings by the foreign students in the host country. The comparison of the host cities reveals that Budapest should be considered as a separate category being different from the other cities in many respects. Although, the assessment of the other three university centres (Pécs, Debrecen and Szeged) received similar evaluations (close average values) but some kind of order developed between them in which Szeged and Pécs are perhaps regarded in a little bit more favourable position than Debrecen. There is a lot to be improved to broaden the studentification process in these cities particularly in four fields. The evaluations can certainly be considered useful in the sense that they help to identify those services which are problematic in any terms (price or quality).
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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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Landscape shape index, as a potencial indicator of urban development in Hungary
78-88Views:348The study of settlement shape, morphology and structure is a classic topic of urban geography. Since the 1960s multiple shape indices have been developed. Urban patterns were then compared with geometric forms or, alternatively their temporal changes were tracked and analysed. In the current study we adapted the landscape shape index (LSI) to analyse the historical shape development of eight Hungarian cities. The LSI is capable to demonstrate the functional and mutual relationship between the developed area and their immediate physical and natural environment. Over the past 230 years the land area of the studied cities has increased manifold for several reasons: on average, an areal increase of 10.4 to 24.5 was observed for the eight settlements, while their perimeter increased by 8.8 to 30.3 times. Simultaneously with their size growth, the studied cities are characterized by an increasingly fragmented and dissected ground plans. Consequently, due to the longer border between the developed areas and the adjacent natural zones, urban areas have become increasingly sensitive to environmental effects over the past century, while mutual ecological and environmental interactions has also considerably increased between the adjoining zones. In general, cities of hilly and low-mountain areas had the highest LSIs, whereas cities located on relatively flat grounds had comparatively low LSIs. We also investigated the rank correlation of the historical change of LSI of the studied settlements. Cities of high positive correlations (> 0.9) were classified into two major categories. Miskolc, Pécs, Szeged and Kecskemét belonged to the group of higher LSIs, whereas Székesfehérvár and Nyíregyháza fell into the class of medium LSIs and the third category included Debrecen and Győr, cities of low (< 0.9) LSIs. Based on the temporal trends of the LSIs, our results provide applicable information for decision makers in order to monitor, manage and track their investments, city management policies and infrastructural development strategies.
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Investigation of the wind power potential of the Hernád valley
93-107Views:43The University of Debrecen, Department of Meteorology has carried out research into the climatic and social-economic conditions of the Hernád valley in the scope of a scientific project (OTKA K 75794) between 2009 and 2012. The aim is to find out the optimal area for wind and solar energy, as well as biomass utilization. Our purpose is to work out a model wherein the complex evaluation of natural and social-economic conditions and effects can eventually result in a sustainable and conflictfree land use. The results of the research will be useful in working out a regional improvement based on the use of renewable energy sources to help the local decision-making process.
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Urban vegetation classification with high-resolution PlanetScope and SkySat multispectral imagery
66-75Views:529In this study two high-resolution satellite imagery, the PlanetScope, and SkySat were compared based on their classification capabilities of urban vegetation. During the research, we applied Random Forest and Support Vector Machine classification methods at a study area, center of Rome, Italy. We performed the classifications based on the spectral bands, then we involved the NDVI index, too. We evaluated the classification performance of the classifiers using different sets of input data with ROC curves and AUC values. Additional statistical analyses were applied to reveal the correlation structure of the satellite bands and the NDVI and General Linear Modeling to evaluate the AUC of different models. Although different classification methods did not result in significantly differing outcomes (AUC values between 0.96 and 0.99), SVM’s performance was better. The contribution of NDVI resulted in significantly higher AUC values. SkySat’s bands provided slightly better input data related to PlanetScope but the difference was minimal (~3%); accordingly, both satellites ensured excellent classification results.
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Climate change: Hungary’s perception and how we adopt renewables against it
58-65Views:16The aim of the research is to present the effects of climate change in Hungary, the public opinion on climate change and the related social acceptance of renewable energy sources and the reasons for their adaptation. Previous surveys have shown that the Hungarian population is aware of the dangers of climate change, yet they are less willing to act against either climate change or pollution. Global climate change threatens peripheral regions more than central regions, as several studies have shown. Hungary has so far successfully met its climate targets but is still far from reaching the 2050 climate neutrality target. The financial and economic situation of the Hungarian population does not currently allow them to widely adopt the opportunities offered by renewable energy sources, but those who can afford to invest in the technologies do so primarily for the financial savings, not to fight climate change.
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Geoinformatic background of geothermal energy utilization and its applications in East Hungary
145-152Views:166Powerful geothermal energy utilisation requires geoinformatic tools from potential surveying through the designing and setting of geothermal systems to certain operational tasks. However, practical data processing strongly depends on the elaboration of basic data and information, the type of the geothermal energy harvesting system and the character of the calculation demonstrated by case studies from East Hungary, in addition the usability of the resulted maps are also presented. Besides their usability for investors these maps could be refined in the location of the development before hydraulic/heat transport modelling.
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Statistical Indices of Land Use Changes and Nutrients Balance of Tomatoes and Peppers Production in Jordan Valley and Highlands (1999-2019)
65-76Views:199Climate change has caused pressure on water resources in Jordan. This was accompanied by the Syrian refugee crisis during the period 2009 to 2019. This descriptive study was conducted in the University of Debrecen, during the years 2020 and 2021 within the course of sustainable land use by collecting official statistical data from reliable sources in Jordan on the production of tomato, pepper, and paprika during five years 1999, 2004, 2009, 2014 and 2019 to compare the change in land use, crop sown structure, country production, unit area average yield and estimation of unit area pollution with major nutrients. The study showed an increased land used for the production of vegetables by (+ 37.84%) during the period from 2004 to 2014, high productivity per hectare for three crops from 2014 to 2019. Jordan had the highest tomato and paprika crop yields in 2014. The reason is due to the increase in the local and global demand for these crops along with other reasons, which have promoted the use of mass production agricultural techniques, the most important of which is chemical fertilization. Which caused the accumulation of phosphorus and potassium in soils.