The papar deals with the possibility of different types of seas protection from ballast waters, starting with administrative measures up to the technologies proposals by which those waters could be treated. The problem of ballast waters in the Montenegrin part of Adriatic Sea is in focus in this paper, and the proposal for protection measures are elaborated.

The aim of this paper is to present the current distribution of the species Corbicula fluminea and Corbicula fluminalis with new findings in Serbia. During the investigation performed from 1998-2008, these taxa were detected at 19 localities. It is noted that C. fluminea is well adapted to particular aquatic ecosystems, whereas C. fluminalis seems to be rare in Serbian waters. Wide distribution of alien clams, according to our results, showed that heavily modified main water ways are suitable recipient areas for introduction and adaptation of allochthonous organisms.

The analysis of breaks and gaps frequences in the fish species Alburnus alburnus from different localities of rivers Kolubara, Sava and Danube, were showed the highest values that were above the presumed critical zone (3.0-3.5% of changes). At some of localities examined in May and October 2008, these values were much more elevated that the level of spontaneous changes normally seen in the controls in laboratory animals and in fish of relatively clean waters. Results that were obtained for these localities indicate to periodical or permanent contamination with genotoxic agents.

This paper presents the results of assessment of dredging activities at the Romanian side of the channel on the quality of water and sediment in the Begej channel (in Serbia). Sediment monitoring results have pointed to the increasing content of metals in surface sediments, as well as increased concentrations of some metals (Cd, Ni and Cr) compared to the period from 2008. Results of the water quality after the dredging at the Romanian side shows low metal concentrations, which is probably caused by coprecipitation of metal in the iron in forms of amorphous and hydrated oxide. Monitoring of water and sediment should be conducted continously through the year in order to follow the trend of sediment and water quality and targeted when we know the exact time of some of the activities in the channel.

The city of Novi Sad uses groundwater as drinking water source. For this purpose only water from Danube alluvium is used, and the water is abstracted at three sites. The Danube water and sediment quality in the zone of the drinking water sources is of great importance, as the river Danube recharge alluvial aquifer. The microbiological quality of these environments was monitored, in order to determine their influence on drinking water quality. The water characterization was carried out using sanitary and ecological microbiological parameters of Danube water and sediment.

The results of microbiological analyses of raw water of two water supplies of city of Novi Sad (Ratno Ostrvo and Petrovaradinska Ada) are presented. The sampling was performed monthly during 2008 and 2009. The following parameters were monitored: aerobic mesophilic bacteria count at 37 deg C, organotroph count (water categorization according to Kohl), facultative oligotrophs, lipolitic and hydrocarbon-oxidizing bacteria count. The count of organotrophic bacteria was determined using low nutritive R2A medium. In addition, water was classified according to enzymatic activity of water, expressed as index of phosphatase activity (IFA).

In this work results from April to September 2009 are presented, which comprosed analyses of samples from 15 stations along Montenegrin coast. The main aim was to estimated level of eutrophication and phytoplankton community characteristic for eutrophic area. Maximum mean value of microplankton of 8.4 x 10**5 cells/l was noted in the inner part of Bokakotorska Bay. This area has maximal values throughout all period of investigation. It is result of waters dynamics and influence from the coast. In the open sea values were lower, about 10**4 cells/l. These results show that Montenegrin coast is an eutrophic region. Some phytoplankton organisms characteristic for eutrophic region were found also. The most abundant species was Thalassionema nitzschioides with maximum mean value of 8.4 x 10**5 cells/l.

Qualitative and quantitative phytoplankton analysis was determined using standard microscopic methods and high performance liquid chromatography (HPLC) in the Bay of Kotor, seasonally, from April 2008 to March 2009. Diatoms represents dominant group of microphytoplankton with maximum in spring period. Dinoflagellates reached maximum value in summer period, and followed by cyanobacteria bloom. Dominant biomarkers, fucoxanthin, alloxanthin, 19'-heksanoloksifukoxanthin, zeaxanthin and chlorophyll b, show a similar distribution as the appropriate phytoplankton assemblages during the researches in Kotor Bay.

Marine sediments are very important for transport, fate and influence of heavy metals in marine ecosystem and therefore they represent good indicator of its ecological status. A great attention has been given in the last two decades in the Mediterranean region to the determination of heavy metals concentration in marine sediments through the monitoring programs, as well as to the studies of heavy metals distribution and their effects on biota. This paper presents the concentrations of Cr, Ni, Cu, Cd, Pb, and Zn determined by EDPXRF method, in the surficial sediment samples taken from six location in the coastal region of the South East Adriatic and their distribution in the investigated area. It can be noticed the influence of the Bojana river regarding the content and distribution of selected heavy metals.

Quality of groundwater from aquifers used for water supply in the town of Zrenjanin, does not meet the drinking water quality requirements. Among the basic problems are the high content of natural organic matter and arsenic, but also sodium and boron. This paper presents one of possible alternative of technological solutions for drinking water preparation in Zrenjanin. Research has lasted three years. The paper presents a only an outline of the drinking water preparation processes.