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This scientific study investigated the use of activated carbon obtained from black alder cone-like flowers for the adsorption of cyanobacteria cells and cyanotoxins from raw water collected from Aleksandrovac Lake. The material was prepared by carbonization and activation, and the water sample was analysed for microcystin and cylindrospermopsin using LC-MS. The results showed that the lake had a high level of Cyanobacteria, making it unsafe for recreational activities. After treatment with the activated carbon, the removal efficiency was 99,8 %, and with no cyanotoxins remaining. The dominant cyanobacteria species was Raphidiopsis raciborskii, which is a producer of cylindrospermopsin. The study demonstrated the potential of activated carbon for removing harmful cyanobacteria and cyanotoxins from water sources.

This debut work offers a stunning look at real vs nominal prices that consider more than just inflation. The inadequate examination of hospitality price comparison is investigated between two non-neighbouring Adriatic east coast countries – Slovenia and Montenegro – using the euro. Hospitality prices are an essential indicator in hospitality markets, destination marketing and management planning. Using 73 monthly time-series data for the economic crisis period from December 2008 to December 2014, this period covers one shock in a series. One of the key managerial features of cointegrated spatial hospitality price spread was that Montenegro followed Slovenian hospitality prices. Hospitality prices in Montenegro and Slovenia tend to be weakly integrated into the long term and seasonally driven in the short term. In addition, the econometric experimentation has given a theoretical novelty for underpinned and undermined tourism economy modelling in normalities. This state-of-the-art econometric feature is included in a customary vector error correction model (VECM). Robust applied results recognise that hospitality prices in Montenegro are domestic driven and in Slovenia Eurozone driven. This finding is relevant for applied economics on obtaining a normally distributed price model. Its theoretical and managerial implications are vital for hospitality economics, marketing and tourism management.

The impact of urbanization and modern agricultural practice has led to accelerated eutrophication of aquatic ecosystems, which has resulted in the massive development of cyanobacteria. Very often, in response to various environmental influences, cyanobacteria produce potentially car-cinogenic cyanotoxins. Long-term human exposure to cyanotoxins, through drinking water as well as recreational water (i.e., rivers or lakes), can cause serious health consequences. In order to overcome this problem, this paper presents the synthesis of completely new activated carbons and their potential application in contaminated water treatment. The synthesis and characterization of new active carbon materials obtained from waste biomass, date-palm leaf stalks (P_AC) and black alder cone-like flowers (A_AC) of reliable physical and chemical characteristics were presented in this article. The commercial activated carbon (C_AC) was also examined for the purpose of comparisons with the obtained materials. The detailed characterization of materials was carried out by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), low-temperature N2 physisorption, and Field emission scanning electron microscopy (FESEM). Preliminary analyzes of the adsorption capacities of all activated carbon materials were conducted on water samples from Aleksandrovac Lake (Southern part of Serbia), as a eutrophic lake, in order to remove Cyanobacteria from water. The results after 24 h of filtration showed removal efficiencies for P_AC, A_AC, and C_AC of 99.99%, 99.99% and 89.79%, respectively.

Akumulacije predstavljaju važan vodni resurs namenjen dugoročnom snabdevanju vodom za piće, ali uprkos tome ne postoji adekvatan plan njihove zaštite. Predmet ove doktorske disertacije jeste praćenje prostorne i vremenske dinamike fitoplanktona akumulacije Vrutci, sa posebnim osvrtom na dinamiku potencijalno toksične cijanobakterije Planktothrix rubescens. Analiza je obuhvatala utvrđivanje sastava, brojnosti i biomase fitoplanktona na tri lokaliteta (Vodozahvat, Nikolići i Omar) i duž vodenog stuba tokom perioda od decembra 2013. do decembra 2015. godine. Pored toga praćeni su i osnovni fizički i (bio)hemijski parametri, takođe po mesecima i po dubini. Osnovni cilj studije je bio prikaz prostorne i vremenske dinamike vrste P. rubescens, otkrivanje najznačajnijih parametara odgvornih za njenu proliferaciju u akumulaciji, kao i procena uticaja „cvetanja“ ove cijanobakterije na dinamiku ostalih članova fitoplanktonske zajednice. Najveća brojnost i biomasa P. rubescens zabeležene su u julu 2015. godine na 6 m dubine (963855 ćel/ml odnosno 30,23 mm3/l) na lokalitetu Vodozahvat. Rezultati su pokazali da su temperatura vode i stabilnost vodene kolone faktori koji u najvećoj meri određuju rast P. rubescens, kao i da ova cijanobakterija ima uticaj na dinamiku drugih algi i cijanobakterija. P. rubescens je tokom perioda stratifikacije formirala metalimnionski maksimum hlorofila a praćen maksimumom koncentracije kiseonika (supersaturacija). Takođe, rezultati su pokazali da rast P. rubescens nije bio toliko uslovljen koncentracijom ispitivanih nutrijenata, iako je akumulacija u proseku bila eutrofna. Neophodno je sprovođenje organizovanog monitoringa osnovnih parametara kvaliteta vode, kao i redovno praćenje vertikalne distribucije biomase P. rubescens u akumulaciji Vrutci., Reservoirs represent an important water resource intended for long-term supply, but despite that, there is no adequate plan for their protection. The subject of this dissertation is the survey of spatial and temporal dynamics of phytoplankton of the Vrutci reservoir, with special reference to the dynamics of the cyanobacterium Planktothrix rubescens. The analysis included determining the composition, abundance and biomass of phytoplankton at three sites (Vodozahvat, Nikolići i Omar) and along the water column during the period from December 2013 to December 2015. In addition, the basic physical and (bio)chemical parameters were also monitored by months and by depth. The aim of the study was to review the spatial and temporal dynamics of P. rubescens, to discover the most important parameters of its blooming in the reservoir and to assess the impact of this cyanobacterium on other members of phytoplankton. The highest abundance and biomass of P. rubescens were recorded in July 2015 at a depth of 6 m (963,855 cells/ml and 30.23 mm3/l, respectively) at the Vodozahvat. The results showed that water temperature and water column stability are the factors that largely determine the growth of P. rubescens, and that this cyanobacterium has a great influence on the dynamics of other algae and cyanobacteria. P. rubescens formed a metalimnion maximum of chlorophyll a during the stratification period, followed by a maximum of oxygen concentration (supersaturation). Also, the results showed that the growth of P. rubescens was not so much conditioned by the concentration of the nutrients, although the reservoir was eutrophic on average. It is necessary to conduct organized monitoring of the basic parameters of water quality as well as regular monitoring of the vertical distribution of P. rubescens biomass in the Vrutci reservoir.

This article expounds one of the first attempts to explore the relationship between tourist arrivals and gross domestic product (GDP) in Montenegro and Slovenia. Both countries are newcomers on the tourist destinations map, derived from what was previously Yugoslav republics existing as a singular emerging tourist destination. Data vector for empirical analysis covers quarterly change of GDP at constant prices and monthly data for tourist arrivals during January 2010 – December 2019 as an endogenous variable. The cointegration is used in the modelling structure. The empirical results confirm research hypothesis of uni-causal relationship of economic growth-led domestic tourism growth in Montenegro and one cointegrated vector. No cointegration vector was confirmed for Slovenia. These results are important for research, policymakers and tourism practice. Considering that, tourism and economic growth have a different distribution of causalities during the expansion period with a boost of tourist arrivals and vice versa during the economic downturn

Predmet ove doktorske disertacije jeste procena diverziteta cijanobakterija u vodama koje se se koriste za vodosnabdevanje i rekreaciju. U tu svrhu, napravljena je baza podataka rezultata mikroskopskih analiza, dopunjena podacima iz publikovane literature. U periodu 2012-2017.god., analizirano je ukupno 503 uzorka, uzetih sa 35 odabranih lokaliteta, pri čemu je identifikovano 148 taksona. Zajedno sa podacima iz 119 pregledanih naučnih publikacija, zabeleženo je ukupno 328 taksona cijanobakterija (iz 84 roda, 28 familija i 6 redova) za ispitivanu grupu voda. Među njima, preovlađuju predstavnici reda Synechococcales (~35%), dok dominira homocitna forma cijanobakterija (~47%). Osim toga, 77 taksona se može okarakterisati kao potencijalno toksično, dok se 9 vrsta smatra invazivnim. Posebna pažnja posvećena je vrstama koje su potencijalno toksične i/ili invazivne, pošto njihova intenzivna proliferacija može predstavljati rizik po zdravlje ljudi i životnu sredinu. U tu svrhu, kao deo istraživanja, analizirana je vremenska dinamika (nedeljna, mesečna i godišnja) cijanobakterija unutar zajednice fitoplanktona, kao i veza sredinskih faktora i cijanobakterija/fitoplanktona u Savskom jezeru, akumulaciji Pariguz i reci Dunav, ali i pojave mikrocistina u akumulaciji Pariguz. Tri ispitivana vodna tela se značajno razlikuju po opštim karakteristikama, hemijskom sastavu vode i dinamici zajednice fitoplanktona. Ipak, povećana mutnoća vode se izdvaja kao faktor koji bi mogao imati važnu ulogu u favorizovanju potencijalno štetnih taksona. Shodno tome, povećanje providnosti vode predstavlja neophodan preduslov za efikasnije upravljanje vodama i kontrolu razvoja vrsta štetnih po zdravlje ljudi i životnu sredinu, poput Limnothrix redekei, Planktothrix agardhii i Cylindrospermopsis raciborskii., supply and recreation. In this regard, a database obtained from the the results of microscopic analyzes was created, supplemented by data from the published literature. In the period between 2012-2017, a total of 503 samples were analyzed, taken from 35 selected localities, and 148 taxa was identified. Together with data from 119 scientific publications, a total of 328 cyanobacterial taxa (belonging to 84 genera, 28 families and 6 orders) were recorded for the investigated group of water bodies. Among them, representatives of the order Synechococcales (~ 35%) predominate, while the homocytic form of cyanobacteria (~ 47%) prevailes. In addition, 77 taxa could be characterized as potentially toxic, while 9 species are considered invasive. Special attention has been paid to species characterized as potentially toxic and/or invasive, as their excesive proliferation can pose a risk to human and environmental health. For this purpose, as part of the study, the temporal dynamics of cyanobacteria (weekly, monthly and annual) within the phytoplankton community has been analyzed, as well as their relationship with environmental factors in the Sava Lake, the Pariguz reservoir and the Danube River and, additionally, the occurrence of microcystins in the Pariguz reservoir. The three observed water bodies differ significantly regarding their general characteristics, water chemistry and dynamics of the phytoplankton community. Nevertheless, high water turbidity stands out as a factor that could play an important role in favoring potentially harmful taxa. Thus, increasing water transparency could be a necessary precondition for efficient water management in terms of controling the development of species harmful to human and environmental health, such as Limnothrix redekei, Planktothrix agardhii and Cylindrospermopsis raciborskii.

Jedinstven vodeni ekosistem Zasavica, koji čini kičmu istoimenog Specijalnog rezervata prirode, u svojoj osnovi podrazumeva rečni ekosistem, a danas predstavlja napušteno rečno korito, odnosno vlažno stanište, uporedivo u ekološkom smislu sa plitkim jezerima, barskim i močvarnim ekosistemima. Postizanje i održavanje dobrog ekološkog statusa vlažnih staništa, gde je ekološki status odraz kvaliteta strukture i funcionalnosti tih ekosistema, predstavlja glavni cilj Direktive o vodama. U Srbiji procenu ekološkog statusa površinskih voda reguliše Pravilnik o parametrima ekološkog i hemijskog statusa površinskih voda i parametrima hemijskog i kvantitativnog statusa podzemnih voda. Predmet ove doktorske disertacije je detaljna analiza cijanobakterija i algi sa ciljem procene ekološkog statusa Zasavice na osnovu parametara fitoplanktona i fitobentosa kao relevantnih bioloških grupa. Dodatno je analizirana i zajednica metafitona, da bi se dobili dopunski podaci o stabilnosti ovog osetljivog ekosistema. Uzorci za analizu fizičkih, hemijskih i biohemijskih (koncentracija hlorofila a) parametara kvaliteta vode, kao i uzorci za kvalitativnu i kvantitativnu analizu fitoplanktona, fitobentosa (epilitskih silikatnih algi) i metafitona, prikupljani su jednom mesečno od decembra 2012. godine do novembra 2013. godine, na dva lokaliteta. Nakon prikupljanja uzoraka, usledila je laboratorijska analiza uzoraka standardnim metodama i izračunavanje potrebnih indeksa. Kvalitativnom analizom cijanobakterija i algi utvrđeno je prisustvo 503 taksona iz 8 razdela (Cyanobacteria, Bacillariophyta, Chlorophyta, Chrysophyta, Cryptophyta, Dinophyta, Euglenophyta i Xanthophyta). Razdeo Bacillariophyta se izdvaja sa 170 identifikovanih taksona. Od 50 prisutnih taksona cijanobakterija, 12 je novo za floru Srbije. Pored toga, 13 taksona cijanobakterija je potencijalno toksično, a među njima tri vrste su i invazivne na području Evrope (Cylindrospermopsis raciborskii, Raphidiopsis mediteranea i Sphaerosper, A unique ecosystem of Zasavica, the basis of the eponymous Special nature reserve, originated as river ecosystem. Nowadays, however, it represents an oxbow lake or wetland, in ecological terms comparable with shallow lakes, ponds and swamps. To achieve and maintain good ecological status of the wetlands is one of the main aims of Water Framework Directive, in which ecological status is defined as an expression of the quality of the structure and functioning of ecosystem. The ecological status assessment of Serbian waters is regulated through the Rulebook on parameters of ecological and chemical status of surface waters, and quantitative and chemical status of groundwaters. The aim of this PhD thesis was to conduct a comprehensive analysis of cyanobacteria and algae in order to assess the ecological status of Zasavica wetland, using phytoplankton and phytobenthos assemblages as relevant biological quality elements. In addition, metaphyton community was analyzed to support the data on stability of this vulnerable ecosystem. Samples for physical, chemical and biochemical (chlorophyll a concentration) analysis of water quality parameters, as well as samples for quantitative and qualitative analysis of phytoplankton, phytobenthos (epilithic diatoms) and metaphyton communities, were collected monthly from two localities, in the period from December 2012 to November 2013. Further, a standard laboratory methods and formulas for calculating selected indices were used to conduct the analysis. A total of 503 taxa belonging to 8 phyla (Cyanobacteria, Bacillariophyta, Chlorophyta, Chrysophyta, Cryptophyta, Dinophyta, Euglenophyta and Xanthophyta) were identified after the qualitative analysis. Bacillariophyta was the most diverse division, with 170 identified taxa. Regarding Cyanobacteria, out of 50 recorded taxa, 12 were new for the Serbian flora. However, there were 13 cyanobacterial species that are potentially toxic and, among them, three are regarded as invasive in Europe (

Substrate specificity of the periphyton community is usually underestimated in both periphyton ecology and biomonitoring studies, thus different kinds of both natural and artificial substrates (of organic and inorganic origin) are employed. Periphyton colonization and successional trajectories are particularly debatable processes when different kinds of substrates are considered. In our field experiment, we deployed four kinds of artificial substrates (two inorganic ones - glass and ceramic, and two organic ones - willow and yew wooden tiles) for the development of periphyton in an urban reservoir referred to as Lake Savsko (Belgrade, Serbia). We comparatively investigated the structure, colonization process, diversity and successional trajectories of periphyton. We also assessed the relationship between the dynamics of algae growth forms (ecological groups) on different substrates and selected abiotic limnological factors. Our objective was to determine whether the type of substrate affects periphyton characteristics at various levels and whether an artificial substrate potentially affects the bioindication capacity of ecological groups. We concluded that all substrates behave similarly at the level of structure and colonization phases, but when considering diversity and successional trajectories, the substrate specificity was demonstrated. Our results suggest that communities developed on inert substrates (glass and ceramic) could provide more realistic insight into complex environmental changes.

The summer phytoplankton community was studied across both vertical and temporal scales in relation to environmental factors in the shallowrecreational Sava Lake. The sampling was conducted weekly at four depths from mid-July until mid-September 2014, in order to detect short-term changes within the assemblages. Besides physical and chemical parameters, meteorological data was also included in the investigation, as that year was characterized with extreme rainfall, which caused serious flooding in the region. The community succession was characterized by a reverse in the cyanobacteria (Codon M) and chlorococcal green algae (Coda F and J). Statistical analyses (RDA) indicated that changes in the community composition and successional pattern could have been due to the mixing regime variations in the reservoir, most likely induced by weather disturbances, especially high precipitation and wind events. These events did not permit massive cyanobacterial development, although they most likely caused resuspension of dissolved phosphorus from the sediment. When observing functional groups, three groups could be distinguished by their response to the above-mentioned parameters: the first prefers high temperature and insolation(Lm, Y, Lo, Xph, W2andM), the second is correlated with precipitation and wind (Td, C, K, MP and X2), while the third group tolerates cloudiness (H1, F, N, X1, D, J and P).

In Serbia Actinocyclus normanii was registered in several rivers and canals. In 1997, it was found as planktonic species in the Tisza River and in benthic samples (in mud) in the Veliki Bački Canal. In 2002, it was found as planktonic species in the Danube–Tisza–Danube Canal (Kajtasovo) and the Ponjavica River (Brestovac and Omoljica). Four years later, in 2006, the species was found in plankton, benthos and epiphytic samples in the Ponjavica River (Omoljica). A. normanii is a cosmopolite, alkalibiontic and halophytic species. It occurs in waters with moderate to high conductivity and it is indicator of eutrophied, polluted waters. Its spread could be explained by eutrophication of surface waters.