Gergely Szabo

• PhD.
• Professor (Assistant) at University of Debrecen

Bevezetés A szélerózió a Föld számos területén, így hazánkban is komoly problémákat és jelentős károkat okoz (zHeNG, x. 2009). Ez a jelenség elsősorban a homoktalajokat veszélyezteti, de a kötöttebb talajok termőképességének leromlá-sában is fontos szerepet tölt be (Guo et al. 2014). A károk egy része lehet mezőgazdasági (talaj-veszteség, termőképe...

Aquatic vegetation species at the genus level in an oxbow lake were identified in Hungary based on a multispectral Uncrewed Aerial System (UAS) survey within an elongated oxbow lake area of the Tisza River under continental climate. Seven and 13 classes were discriminated using three different classification methods (Support Vector Machine [SVM], R...

Environmentally friendly biological mosquito control by Bacillus thuringiensis var. israelensis formulations needs appropriate breeding maps. The mapping accuracy depends on the quality of the used remote sensing data. Further, the mapping is expected to be cost-effective. Our aim was to study the effect of the quality of various remote sensing dat...

Soil water content (SWC) estimation is a crucial issue of agricultural production, and its mapping is an important task. We aimed to study the efficacy of UAV-based thermal (TH) and multispectral (MS) cameras in SWC mapping. Soil samples were collected and the SWC content was determined in a laboratory as reference data and four machine learning re...

Urban sprawl related increase of built-in areas requires reliable monitoring methods and remote sensing can be an efficient technique. Aerial surveys, with high spatial resolution, provide detailed data for building monitoring, but archive images usually have only visible bands. We aimed to reveal the efficiency of visible orthophotographs and phot...

Az utóbbi évtizedekben fokozódó jelleggel tapasztalható szélsőséges klimatikus jellemzők megjelenése, az egyre forróbb és szárazabb nyarak, a szélsőséges hőmérséklet és csapadék előfordulása kedvezőtlenül befolyásolják a faállományaink állapotát. A klímaváltozással kapcsolatban készült előrejelzések arra utalnak, hogy a rövidtávú hatások elsősorban...

The quasi-natural meandering type of alluvial rivers is quite unusual in Central European watersheds. The lack of extensive regulation allows such rivers to shift along their floodplain and cause erosion of natural and agricultural lands. Description of channel morphometric parameters over decadal timescales allows a better understanding of such ri...

The alluvial meandering Sajó River (or Slaná in Slovakian) is a transboundary river of Slovakia and Hungary with a total length of 229 km, of which 124 km is located in the Hungarian territory. Regarding the river regulation and management, Sajó River shows one of the highest rate of free forming sections in compare with other alluvial rivers in Hu...

This chapter will be more practical in nature. It will discuss two fields in which UAV-based photogrammetry proves a particularly efficient tool in geographic and architectural surveys. We will also reflect on the expectable accuracy of these relatively low-cost instruments.

The aim of this chapter is to provide a general overview about the main components of a developed UAS mapping system, the survey, and processing procedure. At first (4.1), a brief introduction is given about basic operational elements and accessories of UAS. Then, recent camera/sensor technologies allowing various survey solutions are going to be d...

This book focuses on small flying drones and their applications in conducting geographic surveys. Scholars and professionals will discover the potential of this tool, and hopefully develop a conceptual and methodological framework for doing the following things: a) Translate their data acquisition needs into specifications. (b) Use the developed sp...

The use of the small format digital action cameras has been increased in the past few years in various applications, due to their low budget cost, flexibility and reliability. We can mount these small cameras on several devices, like unmanned air vehicles (UAV) and create 3D models with photogrammetric technique. Either creating or receiving these...

The aim of our study was to collect hydrological datasets representing the spatio-temporal trends at the Sajó River watershed. A UAV-based meander development monitoring was carried out from 2014 to 2016 at selected river bends where we compared the rate of lateral erosion with the water levels. Our results showed that the hydrological variables pl...

Flume experiments are common tools in investigations of fluvial geomorphology. There is often a need to capture the actual phase of fluvial surface development. Terrestrial laser scanner was used as reference data and compared to three different type of photogrammetric model. The three type were based on three different camera type (Panasonic, GoPro...

A remarkable badland valley is situated near Kazár, NE-Hungary, where rhyolite tuff outcrops as greyish white cliffs and white barren patches. The landform is shaped by gully and rill erosion processes. We performed a preliminary state UAS survey and created a digital surface model and ortophotograph. The flight was operated with manual control in...

Background and aims We examined the influence of litter quality and litter depth on soil microclimate in the detrital manipulation plots in the Síkfőkút Detrital Input and Removal Treatments (DIRT) experiment in northeastern Hungary. We measured the soil temperatures from 06.01.2001 to 06.16.2008 and air temperature from 06.17.2004 to 06.16.2008. M...

Fluvial geomorphologists have tried to describe the outstanding tectonically affected avulsion process of Tisza River at the Great Hungarian Plain by various theoretical concepts. Flume experiments provide the ability to examine the main characteristic processes of a highlighted surface development theory under controlled settings within an acceler...

The aim of our study was to analyze the changes in channel planform geometry of River Sajó between 1952 and 2011. Long term morphological changes were evaluated on the basis of maps and aerial photographs. In every investigated periods the bank edges were vectorized in ArcMap 10. Our results showed that the channel width had a decreasing trend; whi...

Poster presented at the VII. GIS Conference and Exhibition in Debrecen 2016.

Poster presented at the VII. GIS Conference and Exhibition in Debrecen 2016.

Poster presented at the VII. GIS Conference and Exhibition in Debrecen 2016.

Poster presented at the VII. GIS Conference and Exhibition in Debrecen 2016.

abstract Energy production and consumption is a key element in future development which is influenced both by the technical possibilities available and by decision makers. Sustainability issues are closely linked in with energy policy, given the desire to increase the proportion of renewable energy. According to the Horizon 2020 climate and energy...

Presently, the application of digital elevation or surface models have increasing relevance in all areas of scientific research and in practical engineering applications. The ASTER GDEM and SRTM databases are the most widely used digital surface models, due to their free accessibility and global coverage. The SRTM model was produced using a radar-b...

According to the challenge of the reduction of greenhouse gases, the structure of energy production should be revised and the increase of the ratio of alternative energy sources can be a possible solution. Redistribution of the energy production to the private houses is an alternative of large power stations at least in a partial manner. Especially...

The aim of our investigations is to analyse meander and river bank development influenced by natural processes and human activity on the alluvial Sajó River of Hungary. Long term morphological changes of Sajó River were evaluated on the basis of maps aerial photographs (1952, 1956, 1972, 1988, 2000, 2005 and 2011) and the 1:10.000 scale topographic...

The aim of our investigations was to analyse meander and river bank development influenced by natural processes and human activity on the alluvial Sajó (Slaná) River of Hungary. The rate and pattern of meander development was evaluated by analysing horizontal meander parameters. Long term morphological changes of Sajó River were evaluated on the ba...

It is a truism in ecology that environmental heterogeneity increases diversity. Supporting field studies are mostly concerned with a large-scale topographic heterogeneity, ranging from a couple of meters to landscape-scale gradients. To test the role of fine-scale micro-topography on plant diversity, we studied the initial vegetation of recently fi...

In the present study we examined the carbon footprint of a biogas power plant in eastern Hungary, and the economic aspects of its operation. About 65% of the raw materials are transported from within a 12 km radius of the surrounding area; however, the remaining 35% arrives from distances greater than 90 km. In 2013 – taking into consideration the...

According to the Horizon 2020 climate and energy package, legislation has to meet the 20-20-20 target. That means that EU member countries have to reduce the amount of greenhouse gases by 20% to increase the proportion of renewable energy to 20% and to improve the energy efficiency by 20%. Our study is connected to renewable energy issues, the goal...

There are several environmental issues in urban areas that are caused by the unintentional consequences of past activities. One of these issues is the wide application of asbestos cement in roofing materials in the 2nd half of the 1900s. In this study, our goal was to identify different roof types and to determine those with asbestos components usi...

Heating with the use of ambient energy by heat pumps is a very effective way to reduce CO2 emission. However, efficiency, economic and environmental advantages depend on the type of the heat pump and the temperature of the source, the latter usually changes during the heating season. The aim of the paper is to give the annual pattern of the COP and...

In our study, we examined the annual carbon footprint and energy balance of a Hungarian biogas power plant with a power output of 0.637 MW in 2013, with reference to the complete life cycle of the biogas production. The life cycle analysis (LCA) considered the emissions of greenhouse gases (GHG) during the production of feedstock and its transporta...

Manual Land Cover Mapping using aerial photographs provides sufficient level of resolution for detailed vegetation or land cover maps. However, in some cases it is not possible to achieve the desired information over large areas, for example from historical data where the quality and amount of available images is definitely lower than from modern d...

Based on a high ground and spectral resolution imagery, our goal was to identify different rooftypes applying an MS Excel add-in (Hyperspectral Data Analyst) developed by the Department of Physical Geography and Geoinformatics, University of Debrecen. Roofs were detected by using multi-resolution segmentation algorithm on a combinied a normalized D...

Flume and plotting board experiments have been used in fluvial geomorphology for decades. Our goal was to examine a photogrammetric method of creating digital elevation models and ortophotos from digital photographs of a surface development experiment. Our examinations showed that the DEM and the ortophotos can be created by a short period of time...

The aim of our report is to refer on the actual state of small biogas power plants in Hungary summarising the increase in their number and capacity and their effects on climatic change. The above is based on the CO 2 emission of the energetic utilization of biogas and the calculation of its ecological footprint that were compared to the environment...

We carried out wind erosion measurements in the field on three sample areas in Nyírség region, and in wind tunnel. During examinations we measured the erosion and accumulation of soil and studied the process, spatial and time pattern of wind and sheet erosion in areas in various geomorphological settings cultivated intensely with different topsoil...

The aim of this paper is to provide a brief overview about some experiments that we have performed at our department’s fluvial processes laboratory. Actually, this laboratory has a large plotting board which is 10meters long, 3meters wide and 2,5meters deep concrete basin. It has a slight slope for the natural river runoff-processes and it is fille...

Nowadays the role of different high-precision field survey equipment is more and more significant. But using these kind of systems properly is difficult and in many cases we facing high precisious but low quality data. Our goal was to examine the different types of interpolation techniques and comparing them with airborn LiDAR-gained data. Our exam...

A Nyírség 4590 km 2 -es területének a XIX. század közepén megindított integrált környezet-átalakító munkálatok megkezdése előtt a régi térképek szerint mintegy 21%-a (930 km 2) volt az év egészében vagy egy részében vízzel borított terület. A középtájat É-ról, K-ről és D-ről határoló ártéri síkságok és síksági részek – Rétköz, Bodrogköz, Szatmári-s...

The ASTER GDEM database is the latest free global digital surface model of the Earth. Just like the previous system, the SRTM, it is getting more and more popular in wide area of usage. But it is important to know the disadvantages and weaknesses of the database, e.g. the directional-dependent accuracy and the few meters difference between the digi...

Since it is Hungary's second largest river, the River Tisza is important both as a river and because of its active floodplain. The contaminations endanger the aquatic and the related living nature as well as the farming in the active floodplain. The water quality of the river is examined regularly by the competent authority but far less information...

The SRTM as a global and free digital elevation model is often applied as a basic datum in many uses. Internationally we can find examples of the database precision analysis but nationally we can not. In this work our aim was to examine the precision of the altitude data in a piedmont and a plain area. In the course of it a TIN-model made of the co...

In the last decade more and more science deals with the problems of the floodplain sedimentation and the higher peaks of the flood water-level, with the same discharge drew the attention to these issues. This process can be explained by the diminution of the cross-section. Since the width of the active floodplain is stabile, the diminution is the c...

The SRTM as a global and free digital elevation model is often applied as a basic datum in many uses. Internationally we can find examples of the database precision analysis but nationally we cannot. In this work our aim was to examine the precision of the altitude data in a piedmont and a plain area. In the course of it a TIN-model made of the con...

Anthropogenic landforms affect ecological patterns in the landscape. This investigation concerns three parts of the Upper Tisza region, where the most significant landforms are flood-control embankments and the country roads running on their crowns. Analysis of space images, topographic maps and field observations show that these embankments exert...

Seven kinds of natural hazard common in Hungary were studied by the collective of authors. These are: floods, waterlogging, droughts, wind erosion, mass movements, earthquakes and cloudbursts. Their study partly was based on the frequency of occurrence in the past (droughts, earthquakes and cloudbursts) in other cases empirical data were involved (...

In the study we tried to quantify the subcarpathian deforestations, which are considered to be one of the courses of the last-year floods. As a sample area we have chosen the terrritory of river Nagyág and river Talabor. On the basis of a topographic map on a scale of 1:100 000 we surveyed the forest stock of year 1994, then by means of field-wande...

A hazai fiatal homokmozgások korának meghatározására kutatásokat végeztünk a Nyírség és a Duna-Tisza köze lepelhomokkal borított mintaterületein, másrészt laboratóriumi és terepi széleróziós kísérleteket folytattunk a különböző textúrájú talajok erodálhatóságának meghatározására, továbbá a defláció elleni környezetkímélő védekezés lehetőségeinek fe...

A geomorfológiai, fejlődéstörténeti kutatások keretében új (OSL) és hagyományos (14C, palynológiai) kormeghatározási módszerek alkalmazásával a Nyírségben és a Duna-Tisza közén kiválasztott mintaterületeken olyan új adatokat nyertünk, amelyekkel a holocén homokmozgási periódusokat pontosítottuk. Megállapítottuk, hogy a preboreális, boreális fázisok...