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INVESTIGATION OF SOLAR INFLUENCE ON THE TERRESTRIAL PROCESSES: ACTIVITIES IN SERBIA

Author(s): Milan Radovanović / Language(s): English Issue: 1/2018

In this contribution, we have summarized the current stage and perspective of cooperation between different scientific institutions in Serbia in the field of the investigation of the solar influences and effects on our planet. These activities involved 14 researchers from 7 institutions. The investigations are based on experimental, theoretical and numerical work and results are published in numerous papers in respected international journals. In order to make better connection and coordination of relevant activities in Serbia with international tendencies int his research field researchers participate in several international projects and programs. Bearing in mind the importance of the Sun's impact on our planet, the lives of people as well on modern technologies the general impression is that it is necessary to improve the existing infrastructure and increase the number of involved scientists. This study aims to present the current tendency of integrating contemporary research, people and technology in our country, in order to establish cooperation with other relevant groups and individuals.

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THE ASSESSMENT OF ARIDITY IN LESKOVAC BASIN, SERBIA (1981–2010)

Author(s): Nikola Milentijević,Jovan Dragojlović,Dušan Ristić,Dragan Demirović,Dunja Bajrami Demirović,Aleksandar Valjarević / Language(s): English,Serbian Issue: 2/2018

In the paper, the aridity is defined on the basis of four climate indices: De Martonne's ndex of aridity, Lang’s Rain Factor and Gračanin’s Rain factor for the vegetation period and hydrothermal coefficient of Seljaninov. While the annual value of the drought index (IDM) shows humid characteristics, the monthly values show the variability of the conditions. The summer months (July and August) are classified as semi-arid months, while the winter months (December–February) are extremely humid. The spatial distribution of the isoarids indicates that the northern part of the basin has the characteristics of a semiarid climate, while the southeastern parts are more humid. The analysis of mean annual values of the drought index indicates in semiarid conditions (1990 and 2000), but also the humid conditions (2005 and 2009). A positive linear trend indicates that there is a tendency towards humid conditions. The significance test confirms the existence of a statistically significant trend. During the vegetation period, semi-arid conditions are present (July–August). April is slightly humid, and October is moderately arid. The Lang’s Rain Factor (KFg) characterizes basin climate as semiarid, while the Gračanin rain factor for the vegetation period (KFm) indicates a moisture deficit in the summer months. Hydrothermal coefficient Seljaninova (HTC) indicates a lack of moisture in July and August. Vegetation period is characterized as insufficiently humid. Irrigation is one of the most important measures for solving drought problems, since the yield varies from year to year.

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Application of the Water Quality Index in the Timok River Basin (Serbia)

Author(s): Dragana Milijašević,Bojan Gavrilović,Suzana Lović Obradović / Language(s): English Issue: 3/2018

The paper presents an analysis of water pollution carried out on the basis of the combined physico-chemical Serbian Water Quality Index (WQI) in the Timok River basin. The analysis covers various parameters (oxygen saturation, Five-Day Biochemical Oxygen Demand or BOD5, ammonium ion concentration, pH value, Water Total Nitrogen or WTN, Total Suspended Solids or TSS, orthophosphate concentration, electrical conductivity, temperature and the fecal coliform bacteria parameter) the values of which were calculated for four hydrological stations within the basin. The data obtained at each measurement station were averaged using the annual arithmetic average mean. The annual WQI values were calculated for a twenty-five year period (1990–2014) and they were in the range between 12 and 92, which means that the quality of water varied, ranging from “very bad” to “excellent”. The obtained results were interpreted and the watercourse quality was assessed using the comparison of water quality indicators according to the Serbian Classification of Surface Waters and the WQI method. The worst water quality was recorded in the Borska Reka River. Certain SWQI values are the result of water quality changes caused by wastewater from human settlements, industrial facilities, agricultural sources and illegal waste disposal sites in the basin.

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Indicators of Specificity of Climate: the Example of Podgorica (Montenegro)

Author(s): Dragan Burić,Radomir Ivanović,Milan Milenković / Language(s): English Issue: 3/2018

Climatic indices complexly display the climate of a place, and certainly influence its more qualitative characterization. In this paper, the specificity of the climate is analyzed, such as the degree of continentality and aridity, in the example of the city of Podgorica. The climate was considered on the basis of the data for almost the entire instrument period (1951–2017). The results obtained for thermal continentality show that maritime influences are primary and predominant, but the influence of the continent is also significant. In a hygric sense, the climate of Podgorica is characterized as poorly arid to poorly humid with significant oscillations during the year. The warmer period of the year, especially the summer, has the characteristics of arid climate. The colder period of the year, especially from November to February, has the characteristics of humid and even perhumidic climate, while the transitional seasons show signs of semi-aridity and semi-humidity.

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DROUGHT ASSESSMENT IN VOJVODINA (SERBIA) USING K-MEANS CLUSTER ANALYSIS

Author(s): Igor Leščešen,Dragan Dolinaj,Milana Pantelić,Srđan Popov / Language(s): English Issue: 1/2019

Droughts are natural hazards that endanger the safety of population, their property and can create serious agricultural and ecological problems over the affected region. An analysis of the Standardized Precipitation Index (SPI) was performed by using the database of sixty years (1956–2016) of the monthly precipitation for the nine meteorological stations in Vojvodina region (Serbia). The SPI has been used for drought determination. The present study investigates the application of k-means clustering methods on the SPI at the 12-month timescale values to detect distinct drought clusters. For the purpose of determining the optimal number of clusters, the Gap Statistics was used. The results show that the total of four clusters (regions) can be identified in Vojvodina: three stations are listed in region 1 (Sombor, Palić, and Novi Sad), two stations in region 2 (Bač and Sremska Mitrovica), region 3 is a single-station region (Bela Crkva), while in region 4, three stations are grouped (Kikinda, Zrenjanin, and Vršac). The Mann-Kendall test has shown that only in region 1 there is a trend in SPI values ranging from arid towards more humid conditions in the 1956–2016 period. In other regions no trend was observed in the data series. These results could contribute to water resources and agricultural planning and management in Vojvodina region and also confirm the usefulness of clustering methods for drought regionalization.

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FOREST FIRES IN FINLAND – THE INFLUENCE OF ATMOSPHERIC OSCILLATIONS

Author(s): Milan Milenković,Vladan Ducić,Jovan Mihajlović,Dragan Burić,Violeta Babić / Language(s): English Issue: 1/2019

In Finland, in the period 1996–2017, 28,434 forest fires were recorded (an average of 1,292.5 per year), and the total burned area was 11,922 ha (an average of 541.9 ha per year). In both cases, a statistically nonsignificant downward trend was recorded. Forest fires in Finland do not represent a particularly significant problem, primarily due to climatic characteristics, well-organized fire protection, and low density of population. The research of climate influence included the Atlantic Multidecadal Oscillation (AMO), the North Atlantic Oscillation (NAO), and the Arctic Oscillation (AO). The statistically significant values (p ≤ .05) of Pearson correlation coefficient were recorded for the August values of NAO and the surface area of burned forest (−0.44), the June values of NAO and the average surface area of forest burned per fire (−0.51) and the May AO values and the average surface area of forest burned per fire (−0.45). For the June values of NAO and the average surface area of forest burned per fire, the Lomb periodogram shows four significant peaks, and the match is at two, at 2.4 and 3.4 years, which supports the hypothesis of the connection between NAO and forest fires in Finland.

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Zapis zakończenia eksploatacji rud Zn-Pb w osadach rzeki i małych zbiorników wodnych

Author(s): Dariusz Ciszewski,Sylwia Cichoń,Agata Wojtal / Language(s): Polish Issue: 3/2018

The text describes the reaction of a small river on closure of the metal ore exploitation. Changes in the pollution and composition of representative diatom species have been reconstructed in a river and reservoirs sedi-ments. The rapid recovery of the aquatic system immediately after mine closure was documented, however the re-action was not well reflected in all investigated sediments.

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Regionalizacja – wybrane zagadnienia

Author(s): Andrzej Richling / Language(s): Polish Issue: 1/2018

The article contains a discussion of the basic principles of regionalization with particular emphasis on problems that despite the introduction of modern techniques still raise and are not clearly understood.

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Propozycja delimitacji mikroregionów fizycznogeograficznych Pojezierza Kaszubskiego w świetle współczesnych źródeł i metod badawczych

Author(s): Mariusz Kistowski / Language(s): Polish Issue: 1/2018

The paper presents the author’s proposition of Cassubian Lakeland natural border and its divisionon physical-geographical microregions on the background of previous experiences. Two main groups of natural component features: relief (elevation a.s.l., slopes and topographic wetness index) and geological formations according to lithology of shallow subsurface geological sediments were adopted to regions delimitation. 78 litho- and hydrogenic (including valleys and glacial channels) regions were delimitated and described with application of chosen metrics concerning their shape and relief. The comparison of study results with former propositions of Cassubian Lakeland microregionalisation proved the necessity of two regions levels delimitation on the lowest levels of physical-geographical regionalization. The nanoregions– better correspond with study results – should be delimitated next to microregions.

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Doliny rzeczne – kłopot regionalizacji fizycznogeograficznej

Author(s): Tomasz Grabowski,Andrzej Harasimiuk,Anita Gerlée / Language(s): Polish Issue: 1/2018

The article discusses the specific “role” of river valleys in physico-geographical regionalization. Examples of difficulties related to the inclusion of river valleys into high-ranking regional units are presented. The regularities of gradual “disappearance” of carthographic information about river valleys on maps, during the transition to higher levels of regionalization, were presented.

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Trudności wyznaczania granic mezoregionów fizycznogeograficznych w dolinach na przykładzie fragmentu Pradoliny Toruńsko-Eberswaldzkiej

Author(s): Rafał Kot / Language(s): Polish Issue: 1/2018

The paper presents the difficulties in delimiting the boundaries of physico-geographical mesoregions in valleys. The study emphasizes that relief is one of the most important criteria in delimiting physico-geographical regions. The method of delimiting the boundaries of regions within the valley is discussed using the example of the Toruń Basin mesoregion.

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ДИНАМИКА ФЛОРАЛЬНОГО ОРГАНОГЕНЕЗА SYRINGA JOSIKAEA JACQ. ПРИ ИНТРОДУКЦИИ В УСЛОВИЯХ АРКТИЧЕСКОГО КЛИМАТА Г. МУРМАНСКА

Author(s): Daria A. Morozova,Natalia Vladimirovna Vasilevskaya / Language(s): Russian Issue: 4 (165)/2017

Research data of the morpho-physiological analysis of the generative buds of Syringa josikaea Jacq., introduced in Murmansk, are presented. It is shown that in conditions of the Arctic climate the differentiation of axes of the inflorescence and organogenesis of flowers can occur both a year before flowering and in the spring period two or three months before its inception. The polyvariety of the floral organogenesis of the Hungarian lilac, growing in different districts of Murmansk has been revealed. Experimental data on the asynchronous processes of the lilac floral differentiation were first obtained in the Arctic.

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МОНИТОРИНГ ЭКОСИСТЕМЫ ОЗЕРА ГИМОЛЬСКОЕ (РЕСПУБЛИКА КАРЕЛИЯ)

Author(s): Nikolay Viktorovich Ilmast,Yaroslav A. Kuchko,Tamara Yu. Kuchko,Denis S. Belyaev,Nikolai Petrovich Milyanchuk / Language(s): Russian Issue: 4 (165)/2017

Research results of the integrated assessment of the current state of the Gimoly Lake ecosystem, western Karelia, are reported. The hydrobiological indices of the Lake Gimoly show that it is a mesotrophic water body with elevated plankton and benthos evolution levels in bays. Its fish population consists of 16 species. The main targets of amateur fishing are vendace, bream and pike. The roach and perch resources are not completely used. Lake Gimoly is a water body of the highest commercial fishing category because it is inhabited by some valuable fish species such as whitefish, pike-perch and vendace.

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КРУГОВОРОТ УГЛЕРОДА В ЕСТЕСТВЕННЫХ И АНТРОПОГЕННО ИЗМЕНЕННЫХ ТАЕЖНЫХ ЭКОСИСТЕМАХ

Author(s): Maria G. Yurkevich / Language(s): Russian Issue: 4 (165)/2017

The article presents an overview of the current state of the research on the carbon cycle in biological systems. In the last century the human activity related to transformation of natural landscapes has dramatically increased. In some places the human impact has completely changed the biogeochemical cycle of one of the most important biogenic elements – carbon. Especially significant changes are observed in such relatively conservative systems as soils that are not able to recover as fast as plant and animal communities

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ОСОБЕННОСТИ СТРУКТУРЫ ВЗАИМОСВЯЗЕЙ PHLEUM PRATENSE L. С ДРУГИМИ КОМПОНЕНТАМИ МНОГОЛЕТНИХ ТРАВОСТОЕВ В УСЛОВИЯХ КАРЕЛИИ

Author(s): Lyubov P. Evstratova,G. V. Evseeva,Sergey Smirnov,Elena V. Nikolaeva,Ivan V. Evstratov / Language(s): Russian Issue: 8 (169)/2017

The article is concerned with the results of the 9 year observation of the two and three-component grass stands, formed on the basis of different types of perennial grass, considering their long-term combined use. It was noted that the level of productive longevity of grass stands was largely determined by their botanical composition. Characteristic features of the structure of interdependences for timothy grass with other components are revealed. It was established that the mass share of P. pratense in the timothy-fern grass stands declined with the increasing period of the grass use, yielding the dominant position to Festuca pratensis Huds. In the grass stands with the brome grass, timothy grassland predominated (66,5 %) only until the third year of life, and later Bromopsis inermis Leyss gradually depressed its development. In a three-component grass stand, the meadow grassland, beginning from the third year of its use, dynamically increased the mass fraction (up to 93,0 %), replacing timothy grass and meadow fescue. The introduced species – perennial ryegrass and festulolium influenced the grass stand development only during the first three to five years of use. Practically, in all studied variants of the experiment, a clearly expressed regularity of the decrease in the mass share of timothy grass from the 1st to the 3rd cut was observed irrespective of the year of grass use. It is probably conditioned by the antagonistic nature of the relations of P. pratense with other representatives of grass stands.

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ASSESSMENT ON THE IMPACT OF THE TRIPURA EARTHQUAKE (JANUARY3,2017, MW= 5.6) IN NORTHEAST INDIA

Author(s): Jimmy Debbarma,Jatan Debnat / Language(s): English Issue: 1/2021

The northeastern part of the Indian subcontinent, considered as the most active seismic zone of the Indian subcontinent, was hit by an earthquake of Mw5.6 on January3,2017. The epicenter of this earthquake was Kanchanbari located in the Dhalai district of Tripura. The present study aims to assess the environmental and socio-economic impact of this earthquake in the vicinity of the epicenter. To assess and determine the level of damage, the affected areas were visited during the first week of the 2017 earthquake. Various Government offices were also consulted to acquire data on damages caused by the earthquake. Moreover, Remote Sensing and Geographical Information System (RS & GIS) techniques were applied to address the influence of this earthquake on bank erosion. During the field visit, the striking features of soil liquefaction generated by the earthquake were observed in the flood plain area of the Manu River. Landslide, with three casualties in India and the neighbor Bangladesh, and damages of infrastructure were also reported. Additionally, an assessment of the bank erosion study revealed that the rate of the post-earthquake bank erosion increased to 592%, compared to the pre-earthquake bank erosion within the study length of the Manu River. The findings highlighted that the impact of this earthquake is minimal. However, the seismotectonic features and observation of the liquefaction within the risk zone of the earthquake indicate a possible significant threat for the future.

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DEBRIS FLOWS IN KRESNA GORGE (BULGARIA)—GEOMORPHOLOGICAL CHARACTERISTICS AND WEATHER CONDITIONS

Author(s): Dimitar Krenchev,Rossitza Kenderova,Simeon Matev,Nina Nikolova,Georgi Rachev,Martin Gera / Language(s): English Issue: 1/2021

Over the last decades, numerous extreme climate events such as extreme temperatures, droughts, heavy precipitation, and storms associated with climate change have been recorded in many countries, including Bulgaria. As a result, geomorphological hazards such as landslides, debris flows, mudflows, high-speed soil erosion, etc. often occur on the territory of the country. The debris flow is one of the most common hazardous processes in small catchments of the main river basins in Bulgaria. The Kresna Gorge located in the middle part of Struma River valley is a typical area with such processes which often cause the damages to the E79 international highway. The purpose of the present study is to characterize debris flows in Kresna Gorge (southwestern part of Bulgaria) by comparative analysis between the two events (occurred on May 24, 2009 and July 28, 2019). In order to achieve the aim of the study the geomorphological features and flow type of 2019 event were identified and the results were compared with the previous publications which investigated the event on May 24, 2009. In the present paper, the sediments and the type of transportation of the investigated event (July 2019) were determined by grain-size and clast-shape analysis. The impact of weather conditions on debris flow occurrence was shown by the analysis of the synoptic conditions on the day before the event. The results of the study bring to clarifying the geological-geomorphological and meteorological factors for the occurrence of debris flow and are important for geomorphological hazard management.

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SPATIO-TEMPORAL VARIABILITY OF PRECIPITATION OVER THE WESTERN BALKAN COUNTRIES AND ITS LINKS WITH THE ATMOSPHERIC CIRCULATION PATTERNS

Author(s): Dragan Milošević,Rastislav Stojsavljević,Szilárd Szabó,Uglješa Stankov,Stevan Savić,Luka Mitrović / Language(s): English Issue: 1/2021

Temporal and spatial variability of annual and seasonal precipitation from 71 stations located in Western Balkan (WB) countries (Serbia, Bosnia and Herzegovina, and Montenegro) and their correlations with nine atmospheric circulation patterns was examined for the period 1950–2016. Annual precipitation increased significantly throughout the WB (from 2% to 8% per decade) on 20% of stations located mainly in the mountainous western Serbia and eastern Bosnia and Herzegovina. Winter was characterized by non-significant precipitation changes in most of the studied area, with only a few stations characterized by significant precipitation increase (up to 12% per decade) in the mountainous area of WB, and a few stations characterized by significant decrease (up to –6% per decade) in the Pannonian plain. Significant precipitation increase was noticed on 15% of the stations in spring, while it was noticed on 17% of the stations in autumn. Summer precipitation decreased significantly (up to –5% per decade) on a limited area of northern Serbia (6% of the stations), while the majority of stations showed non-significant increase. The strongest influences on annual precipitation in WB region are of the Arctic Oscillation (AO) and Mediterranean Oscillation (MO), leading to the precipitation decrease during their positive phases. Winter precipitation is significantly negatively correlated with AO, East Atlantic/Western Russia oscillation (EA/WR), and North Atlantic Oscillation (NAO) and has a significant positive correlation with Western Mediterranean Oscillation (WeMO) on the majority of stations. MO has the strongest influence on summer precipitation in WB region leading to precipitation decrease, while AO has the dominant influence on precipitation in the region during autumn.

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PUBLIC PERCEPTION OF CLIMATE CHANGE AND ITS IMPACT ON NATURAL DISASTERS

Author(s): Vladimir Cvetković,Lazar Grbić / Language(s): English Issue: 1/2021

The aim of the research is the examination of the factors influencing the public perception of climate change and its impact on natural disasters. This paper presents the results of quantitative research regarding testing the central hypothesis where education is the predicting variable of public perception of climate change and its impact on natural disasters. A multivariate regression analysis was used, identifying the extent of the total scores of the main dependent variables (perception of vulnerability to climate change, perception of the climate change impact on natural disasters, knowledge and fear scores) were associated with five demographic and socio-economic variables: gender, age, marital status, education level, and employment status. A series of 208 face-to-face interviews were conducted during the beginning of 2020 on the central squares in the selected cities in Serbia, Belgrade (76.92%) and Sremska Mitrovica (23.08%). The results showed that education level was the most effective predictor of the mentioned research variables. Besides, employment status has been found to affect perceptions of vulnerability, while age affects the perceptions of climate change. Based on the obtained results, policies and strategies to improve people's awareness of climate change must take into account a comprehensive understanding of behavioral dispositions.

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VARIABILITY AND TRENDS OF PRECIPITATION ON LOW- AND HIGH-ALTITUDE STATIONS IN SERBIA

Author(s): Igor Leščešen,Dragan Milošević,Rastislav Stojsavljević / Language(s): English Issue: 1/2021

For the trend analysis of the annual, seasonal and monthly precipitation linear regression and Mann–Kendall (MK) tests at the 5% significance level were applied. In this study, precipitation data from two stations in Serbia for the 1949–2019 period were used. Results indicate that increasing trends of precipitation for the selected station can be observed but these trends were not statistically significant according to MK test. Then again, MK test has shown that only on Palić station during autumn precipitations have statistically significant increase during the observed period with a p value of 0.0441 at the significant level p=0.005.

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