There are just a few data about species and quantities of phytobenthos for the Montenegrin coast, so that us one of the difficulties for the monitoring of changes caused by human impact. With the aim to contribute to the better knowledge of phytobenthos in this area we described distribution of Cystoseira barbata in the inner part of the Boka Kotorska bay and state of the environment in this aquatory.

Factors controlling of arsenic content in underground water are commented on the base of experimental obtained results of analysis of water quality from October to November 2006. The influence of water quality parameters and temperatures of water on examined locations of waterworks of middle Banat, south from Zrenjanin, public wells in Zrenjanin and waterworks north from Zrenjanin, on arsenic content is found.

Groundwater of Serbia is strategic natural resource which provides drinking water for about 75-80% of population. This resource is however not properly utilized and protected from pollution in accordance to its importance. Accepting to achieve the targets of EU Water Frame Directive, Serbia is in fact confirms the aim to better explore and protect the groundwater. The paper describes different activities planned under the project prepared in 2006 by the experts from leading Serbian institutions in water sector and in geology. Implementing this project until 2011 could create an ambience for future more sustainable exploitation and protection of the groundwater.

Research of phytoplankton is conducted in different seasons during 2004 and 2005. River Bojana and Ada Bojana are analyzed on several locations. The objective of research is based on algae as reliable indicator of water quality and ecological condition of water. We would like to show the need for protection of these water ecosystems from permanent contamination, basically sewage waste. Saprobiotic index is determined by Gulyas Pal method. Pantle Buck method is used to calculate saprobiotic level. Chlorophyll A is analyzed by spectrophotometer. Presence of Cyanophytae was established.

The puddles Novo Ilje 1 and Novo Ilje 2 are aquatic ecosystems periodically filled with moderate salt and alkaline water. In 2003 and 2004 quantitative analysis show the Euglenophyta domination. Trachelomonas taxa are the most common. The algae in planktonic communities are the most numerous in both puddles in researched years.

The salt pond Velika Slatina is the old meander of the river Tamis (Serbia). The ecosystem is periodically fill with moderate salt water. Phytoplankton production was 10 times bigger in 2003 than 2006. Ecological conditions were unfavourable for development of phytoplankton community. Diatoms show as the most abundant component in 2003, but euglenoids were in 2006, when bloom of Gloeotrichia natans f. bucharica Kissel was recorded. Results of biomass analysis also show dominant role of diatoms in 2003 and euglenoids in 2006.

The contents of heavy metals (Mn, Pb, and Cd) in water, sediments and shoots of emersed plants Phragmites communis, Typha latifolia and Typha angustifolia in the area of Bardaca fish pond were analyzed. Species Typha latifolia has shown the best ability for the bioaccumulation of heavy metals tested. Therefore, this species could be recommended as the phytoremediator of these pollutants from polluted waters. The results of this study indicate that the accumulation of tested elements in the water, and their availability to plants are still far from the critical level which may cause disturbance of balans in the Bardaca ecosystem.

Composition of benthic macroinvertebrates and phytoplankton were examined during the period of July-November 2006, for purposes of freshwater quality assessment in protected area of Jegricka water body. Results of research show intensive sedimentation of organic matter in river bed, which is caused by eutrophication processes and small flow velocity in this canalized river of Vojvodina.

In this paper the results of preliminary microbiological investigations of the canal Nadela water quality, done in order to determine level of pollution, are presented. Bacteriological analysis included the monitoring of quantitative composition of the organotrophs, presence of some physiological groups of bacteria and total number and fecal coliforms. Beside of that, level of water phosphatase activity and chlorophyll a concentration as important parameters of waterstate, were determined. Obtained results indicated low quality of the canal Nadela water and overload by organic matter, that cleary reflected negative influence of pollutants presents in that area.

This paper presents the results of the Danube river water quality analysis, using the data set for the period of 2001-2005, provided by the Hydrometeorological Service of Republic of Serbia. Main input parameters - data on water quality resulting from sampling performed generally once per month for relevant parameters, are used according to Water Quality Index (WQI) methodology. Data grouped on a sampling site basis, averaged on a yearly level, resulting with a median WQI of each sampling station are employed to create a synthesized quality indicator. Final result of such an analysis shows a general deterioration of quality expressed using WQI for the observed period.