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Summer - autumnal aspect of thermal regime on Sava lake [Serbia, Yugoslavia]
1997
Popovic, M. | Janac, M. (Institut za vodoprivredu "Jaroslav Cerni", Beograd (Yugoslavia))
Thermal stratification is regularly found in deep lakes, while shallow water bodies remain usually mixed. Despite comparative shallowness, Sava lake (artificial lake), Serbia (Yugoslavia) exibit a prolonged summer stable stratification. Temperature differences between epilimnion and hypolimnion can reach 10 deg C. The steep gradients of up to 3.5 deg C/meter recorded in the metalimnion. The highest differences during a single typical summer day was 1.7 deg C between 0.2 and 0.5 m. Maximum annual thermal accumulation was 112440 J/square cm in 1996.
Показать больше [+] Меньше [-][Physical and chemical characteristics of the Danube river and a part of the Danube-Tisza-Danube channel [Serbia, Yugoslavia] during the period 1991-1996]
1997
Bugarski, R. | Berkovic, M. (Republicki hidrometeoroloski zavod Republike Srbije, Beograd (Yugoslavia))
Drainage of industrial and communal effluents, directly into the water flow, as many hydrotechnical activities, significantly influence the schedule and balance of the processes that take place into water. In this paper, there are represented the results of systematic control of the water quality of the Danube river and DTD (Danube-Tisza-Danube) channel on the parts Vrbas-Bezdan and Becej-Bogojevo, at the control station network of the Republic Weather Bureau (the Republic of Serbia), for the period of 1991-1996. The results show that the most adverse influence of anthropogenic factor is on the part of the flow of the DTD (Danube-Tisza-Danube) channel from Vrbas to the flow into Tisza river.
Показать больше [+] Меньше [-]The possibility of removing heavy metals from waste waters by natural zeolites
1997
Pasalic, S. | Grbavcic, M. | Barbic, F. | Pljakic, E. (Institut za tehnologiju nuklearnih i drugih mineralnih sirovina, Beograd (Yugoslavia))
Over the last several years, the investigations of the natural zeolites application in the sorption processes have been intensified. Purification of waste waters in order to remove lead, cadmium, copper and other heavy metals, is one significant example of such application. In this paper, the investigations results on characteristics of the natural and chemically activated zeolites from the region of Vranje (Serbia, Yugoslavia), are presented. The experiments with zeolites were performed after determination of their physico-chemical characteristics. Adsorptive characteristics were investigated under laboratory conditions, in a liquid medium, depending on granulation and concentration of the heavy metals. As the obtained results show, these natural materials can be used to remove heavy metals from the waste waters.
Показать больше [+] Меньше [-]Perch as a test organism in water quality evaluation
1997
Ivanc, A. | Etinski, M. | Maletin, S. | Djukic, N. | Miljanovic, B. | Pujin, V. (Univerzitet u Novom Sadu, Novi Sad (Yugoslavia). Prirodno-matematicki fakultet, Institut za biologiju)
Perch (Perca fluviatilis) suitability as a water indicator was studied in field and laboratory investigations. It was found out that hematological status of this fish species was a valuable indicator of both temporary and periodical deterioration of dissolved oxygen saturation and can be used as reliable test for water quality evaluation. The anlyzed hematological parametrs were tested for their sensitivity and reliability as indicators of water quality changes. Values of different parameters were given for perch kept under optimal and unfavourable conditions of water oxygen saturation.
Показать больше [+] Меньше [-]Water quality in Yugoslav part of the river Tisza [in the period of 1988-1995] evaluated with method of multiobjective iterative compromise optimalization (MICO)
1997
Krizan, J. (Univerzitet u Novom Sadu, Novi Sad (Yugoslavia). TEMPUS centar)
The aim of this paper is to survey and point to the critical parts of this typically valley river in the chosen period of time, which is, because of its low flow, small turbulence and exceptional social and industrial significance, very susceptible to ecological catastrophes. This paper contains the elaborated state of water quality in Yugoslav part of the river Tisza, during two periods of observation, with usual (1988-1991) and specific (1992-1995) river ecosystem exposure to pollutants. The average annual data of concentration for characteristic parameters in the monitoring stations were compared with method of multiobjective iterative compromise optimalization (MICO) of the influence that different categories of polluters have on the river ecosystem. On the basis of analyzed concentrations of selected parameters and results obtained with method of MICO, it is possible to conclude that the improvement in quality of Yugoslav part of the river Tisza has occurred during the period of 1992-1995.
Показать больше [+] Меньше [-]Saprobiological evaluation of the river Banja and it's tributary Pocibrava [Serbia, Yugoslavia] by the use of macrozoobenthos as indicator
1997
Markovic, Z. (Univerzitet u Beogradu, Beograd (Yugoslavia). Poljoprivredni fakultet) | Miljanovic, B. | Mitrovic-Tutundzic, V.
There were estimated of water quality of the river Banja and its trubutary Pocibrava, Serbia (Yugoslavia), during the period 1991-1994 by seasonal investigations of benthos fauna composition as bioindicators. The results have shown higher diversity of the Pocibrava bottom fauna community (66 taxa) than in the river Banja (53 taxa) where it was more uniform. Both water flows were receiving some organic loading and by the use of macrobenthos indicator organisms it was concluded that they belong to beta-mesosaprobic water quality class.
Показать больше [+] Меньше [-]Primary production of phytoplankton and zooplankton of the Sava reservoir [Serbia, Yugoslavia]
1997
Brkovic-Popovic, I. (Institut za vodoprivredu "Jaroslav Cerni", Beograd (Yugoslavia)) | Mitrovic-Tutundzic, V. | Vulic, D. | Obradovic, V. | Damnjanovic, M.
Primary production of phytoplankton and diversity and biomass of zooplankton of the Sava reservoir (artificial lake), Serbia (Yugoslavia), was studied during the summer and autumn in 1996. The study results were compared with the research results by Perisic et al. (1984) obtained before the dredging of the lake bottom, when bottom sediments with macrophytes were removed. It was found that the water quality was improved in comparison with previous period.
Показать больше [+] Меньше [-]The importance of some members of biocenosis in protecting the ecological balance on the preserved ecosystem Obedska bara [Serbia, Yugoslavia]
1997
Ratajac, R. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Rajkovic, D. | Stojkovic, S. | Bobic, M. | Cokic, S.
The investigations have been done in Krstonosica shaft at 3 points, in February, May and October 1995, and in January and April 1996. They included algae, Rotatoria, Copepoda, Cladocera, and Hydracarina. The species from divisio Bacillariophyta were presented most among the algal species, with 56 species, then from divisio Chlorophyta, with 26 taxons, Euglenophyta 11, Cyanobacteria 9, Pyrrophyta 3, Xanthophyta 2 and Chrysophyta 1. Among animal groups the highest number belonged to the Rotatoria group, 111 taxons have been determined. The highest number was found during autumn season (86), then in spring (73), and only 14 species in winter. The species that mostly prevailed were phytophyl species. The Cladocera group was present with 18 taxons. The phytophyl species from overgrown plants again prevailed. The Copepoda group was present with 10 species and the phytophyl species were prevailed. According to saprobiological characteristics the greatest number belongs to beta-mezosaprobionts, then oligosaprobionts. A small number of species indicates to the eutrophication process and organic pollution of water.
Показать больше [+] Меньше [-][Estimation of water quality of the Bajski canal [Serbia, Yugoslavia] using chemical and biological parameters]
1997
Pujin, V. | Ivanc, A. | Kojcic, K. | Miljanovic, B. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za biologiju)
In the period of 1993-1996 water quality of the Bajski canal (Serbia, Yugoslavia) was followed using certain chemical and biological parameters. Oxygen control ranged from its deficiency to its supersaturation recorded in spring and early summer which moved down in summer and early autumn. A smaller amount of suspended particles points to a sedimentation process provoked also in the canal bed, clearing the way for the development of macrophytes. A diverse zooplankton showed typical seasonal variations. A total of 73 species was recorded including 13 Protozoa (17.8%), 44 Rotatoria (60.3%), 10 Cladocera (13.7%), and 6 Copepoda (8.2%). In summary, the process of water quality deterioration is less evident in this section of the DTD (Danube-Tisza-Danube) hydrosystem (Serbia, Yugoslavia).
Показать больше [+] Меньше [-]Establishing of heavy metals contents of the Sava river sludge [Servia, Yugoslavia]
1997
Maljevic, E. | Stojanovic, Z. (Republicki hidrometeoroloski zavod Srbije, Beograd (Yugoslavia))
The paper provides experimental results of testing the content of heavy metals, and other harmful and dangerous matters of the Sava river sludge (Serbia, Yugoslavia). The testing carried out by the Republic Hydrometeorological Service of Serbia (Yugoslavia), has been in compliance with the program of testing the Sava river water and sludge quality along the river flow. The establishing of sludge pollution range is not based upon values of maximum allowable concentrations. The most complex is the issue of heavy metals contents, since these also represent the natural contents of soil and minerals. However, considering the process of migration and distribution of heavy metals, and other harmful and dangerous matters discharged from utilities, industrial and power supply facilities, provides the basis for estimating the environmental pollution as well.
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