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The function of dominant hydrophytes of the Mostonga [Serbia, Yugoslavia] in water quality bioindication
1998
Stojanovic, S. | Nikolic, Lj. | Lazic, D. (Poljoprivredni fakultet, Novi Sad (Yugoslavia))
The Mostonga, once the tributary of the Danube river, now a water-stream with a conducted regime it represents an important water-streams in West Backa (Serbia, Yugoslavia). The most wide-spread hydrophytes (i.e. plant species with the biggest abundance, covering values and occurrence degree) are: Wolffia arrhiza, Lemna gibba, Lemna minor, Lemna trisulca, Spirodela polyrrhiza, Ceratophyllum demersum, Elodea canadensis, Vallisneria spiralis, Stratiotes aloides, Nuphar lutea, Bolboschoenus maritimus, Typha angustifolia, Typha latifolia and Phragmites communis. Based on the analysis of bioindicating values of mentioned hydrophytes of the Mostonga it can be concluded that the present plant species are significant indicators of eutrophication (considerable organic pollution) as well as the increased contents of nitrogen and nitrogen compounds (nutrients), presence of salt in the soil and weakly aerated and mud base.
Afficher plus [+] Moins [-]The kinetics of phytoplankton and factors which affect on this
1998
Sekulic, G. (Gradjevinsko-Arhitektonski fakultet, Pristina (Yugoslavia)) | Markovic, Dj. | Djokic, V.
The kinetics of phytoplankton is complicated function of phytoplankton present and their differing reactions to solar radiation, temperature and balance between nutrient availabilities and phytoplankton requirements. Computers program for water quality problems helps users interpret and predict water quality responses to natural phenomena. But model parameters and initial condition needs hydrodynamic and hydrologic measures in long time interval, with combination of laboratory studies. Lake Gracanka (Serbia, Yugoslavia) is good example for description of the processes kinetics of phytoplankton. But, simulation model can not be used to guide future monitoring efforts without needing measuring and developing network of measuring station.
Afficher plus [+] Moins [-]Phosphatase activity and microbiological parameters as indicators of the canal waters pollution by the oil industry wastewater [Yugoslavia]
1998
Petrovic, O. | Radnovic, D. | Gajin, S. | Matavulj, M. | Trivunovic, V. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za biologiju)
On the basis of the enzymatic (phosphatase) activity and microbiological analysis as well, the influence of the oil refinery "Vital" - Vrbas (Serbia, Yugoslavia) wastewater to the recipient DTD (Danube-Tisza-Danube) canal water from the microbiological point of view was determined. In addition the efficiency of the factory's waste water purification plant was estimated. The obtained results of the complex microbiological-enzymological analyses indicated a good water quality at the point where the refinery's water supplies plant is situated (site 1). Very low water quality was determined downstream (site 4) and upstream (site 2) from the inflow of the refinery's wastewater's inflow. The later results might indicated the influence of an unknown pollutant in the region. However, the obtained O/H index value suggests that the self-purification ability of the canal waters is still preserved.
Afficher plus [+] Moins [-]Spatial and temporal dynamics of cellulolytic microorganisms in Vlasina [water] reservoir [Serbia, Yugoslavia]
1998
Comic, Lj. | Curcic, S. | Rankovic, B. (Prirodno-matematicki fakultet, Kragujevac (Yugoslavia). Institut za biologiju)
Processes of transformation of organic matter are slowed down so that cellulose which originates from cell walls of Sphagnum is retained long in unchanged form. The highest valises of cellulolytic bacteria (0.33-126.67 bact/ml) were recorded in October. In most cases slightly active species were found, Cellvibrio fulvus was dominant. The participation of fungi in cellulolytic community was significant 23-31.5.
Afficher plus [+] Moins [-]The successions of plankton communities in Grosanica [water] reservoirs [Serbia, Yugoslavia]
1998
Comic, Lj. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za biologiju) | Ostojic, A. | Milosevic, S. | Rankovic, B. | Simic, V. | Timotijevic, V. | Brdar, A.
Within the comprehensive hydrobiological investigation of Grosnica water reservoir (Serbia, Yugoslavia) composition and dynamics of bacterioplankton, phytoplankton and zooplankton, as well as their seasonal successions were studied. The composition of plankton communities varies during the vegetation period in the function of the physicochemical features. Grosnica water reservoir with its microbial features belongs to the 1st-2nd class of bonity according to Kohl. The highest values pf bacterio- and zooplankton were recorded in August, while bruto primary production in September.
Afficher plus [+] Moins [-]Example of calculation of the coincidence of water level and quality parameters of the groundwaters
1998
Marcetic, I. (Rudarsko-geoloski fakultet, Beograd (Yugoslavia). Institut za hidrogeologiju) | Prohaska, S. | Srna, P. | Isailovic, D.
In this paper the short review of the results of calculation of the coincidence between the water level and quality parameters at the gauging station Cuprija-rail bridge (Serbia, Yugoslavia) is presented. The basic principles of the applied method and criteria for the estimation of the statistic significance of coincidence indicators are given. At the end of the analyses and comments of the obtained results, as well as the possibility for application of this methodology are given. The paper gives numerical quantities of the estimated indicators of statistical significance of the coincidence of water level and quality parameters of groundwater. Also, the graphical illustration, which shows the common exceeding probabilities of the water level and quality parameters, is presented.
Afficher plus [+] Moins [-]Biomanipulation in eutrophication process control
1998
Maletin, S. (Univerzitet u Novom Sadu, Novi Sad (Yugoslavia). Poljoprivredni fakultet) | Djukic, N. | Miljanovic, B. | Teodorovic, I.
Amplified and accelerated eutrophication process is a characteritic of a whole variety of small and medium-sized water-bodies, such as channel systems, microreservoirs, ponds, lakes and bank regions of many even bigger ecosystems. During the process, in relatively short period of time, the upper capacity limit of a certain biotop is far too exceeded, which leads to reduced ability of ecosystem's autopurification. As a consequence of such degradation, ecosystem faces a serious discrepancy between members of a biocenosis e.g. in ration producers/consumers/decomposers, which, in the end, causes destruction, e.g. dystrophy of the hydroecosystem. The introduction of diverse fish communities, can, therefore, be one of the basic measures for enabling a sustainable trophic stability, in a sense of keeping a dynamic balance. This measure includes carefully planed fish community - it should consist of three basic components of a trophic food web (planktivore and macrophytovore, bentivore and carnivore). Apart from enabling certain biodiversity considering particular fish species (both quantitative and qualitative), care must be inevitably taken of age structure, as well as fish stock and fishing dynamic, concerning the number, quantity and age.
Afficher plus [+] Moins [-]Sea-water quality and level pollution in the coastal Southern Adriatic [Montenegro, Yugoslavia]
1998
Regner, D. (Institut za biologiju mora, Kotor (Yugoslavia)) | Vuksanovic, N. | Dutina, M. | Stjepcevic, B. | Sestovic, K.
Results on sea - water quality control and level of pollution in the coastal Southern Adriatic (Montenegro, Yugoslavia) were discussed from data collected in 1997. Investigations from Boka Kotorska Bay, coastal sea up to Bojana river mouth and in front of Bojana river mouth were presented separately. For above mentioned areas, basic hydrographic parameters, as well as the level of bacterial contamination were examined throughout the year (1996/1997 period). In Kotor Bay, which is the shallowest and exposed to the strongest land - based sources, as in the Tivat Bay, some changes influenced by anthropogenic eutrophication were already found.
Afficher plus [+] Moins [-]Transboundary issue of Bega canal [Serbia, Yugoslavia] pollution
1998
Cukic, Z. (Univerzitet u Novom Sadu, Novi Sad (Yugoslavia). Prirodno-matematicki fakultet, Institut za hemiju) | Kilibarda, P. | Kojcic, K. | Jovanovic, D.
Using the then years data series of organic load (COD, BOD), ammonia and organic nitrogen, total phosphorus, detergents and oxygen dissolved, a heavy pollution of Bega Canal at the Romanian - Yugoslav Border ("Srpski Itebej" Control Station) is illustrated. High load of organic matters and nutrients as well as extremely low oxygen dissolved content created anaerobic conditions in aquatic environment, are the main characteristics of Bega Canal state at the analyzed location. As the Bega Canal (left tributary of Tisza river) is an international river, a transboundary issue of pollution is considered in this paper.
Afficher plus [+] Moins [-]Sedimentological characteristics and mineralization of sediment in the run-of-the river reservoir Djerdap 1 [Yugoslavia]
1998
Perisic, M. | Markovic, I. | Janezic, V. (Geoinstitut, Beograd (Yugoslavia))
In previous works numerous specific changes of water composition in the Danube backwater effects Iron Gate 1 reservoir (Yugoslavia), have been initiated. By studies of conditions of generation and composition of sediments, the models denying importance of assumption on sedimentological features of deposited materials foreseen by the project, have been established, as it was confirmed with more details by newer investigations. The new data on the character of sediments coincide in all elements with changes of water composition, which was formerly presented, thus the knowledges of these phenomena being in that way more important. The data on composition of the deposited material, the macro and micro-composition are of great importance to perceive the influence of new sediments to the quality of surface and groundwater, especially of the sources for water supply, then in a long term for the sudden high risk processes corresponding to a chemical time bomb. Data have confirmed validity of the model of intensified deposition of allochthonous material with plankton and influence of this phenomenon to the processes trough the downstream section.
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