In this paper some results of investigations of physical, chemical and biological parameters were presented from the parts of Montenegrin coastal sea exposed to the impact of the open waters of the Southern Adriatic sea. As Herceg Novi area is simultaneously the part of the Boka Kotorska Bay (which goes deeply to mainland), eutrophication is more visiable there. Biological parameters were the most visiable indicators of eutrophication during these investigations.

The groundwater quality on the National Park Kopaonik is determined by the chemical and radioactive structure of water, formed through the processes that due to the contact of minerals from the water - bearing rocks and groundwater. Atmosphere precipitation are the main source of the entire resources of the ground water in the national park, and the aggressive components that are carried into the underground are the main catalyst in the process of leaching of the predominant minerals from the water-bearing rocks. In the national park, crystalline and marble limestones have the greatest water potential in the sense of the quantity and quality, and the granite massif dispose with the ground water, with the most complex radioactive structure.

Growing number of population require growing demand for water. In Sremska Mitrovica area geohydrology conditions of neogen sequence have properties of good collector for groundwater. Geological factors are such that atresian groundwater in Sremska Mitrovica area are divided in four hydrogeological zones. In all zones physical and chemical characteristics of groundwater comply with conditions for water supply.

Research of the seasonal dynamics of the zooplankton abundance was carried out during the two-year period from January 2005 to December 2006. The sampling took place in monthly intervals from five different sites from the surface to the bottom of the lake. Taking into concidertion the temperature and oxygen regime the division on the epilimnion and hipolimnion was found out. Significant numerous in the total abundance of the zooplankton accomplish taxa Daphnia sp., Bosmina sp. and Cyclops sp. Zooplankton is more abundant in the epilimnium, in the layer with more favourable temperature and oxygen regime comparing with hipolimnium. Presence of the zooplankton has been recorded in the lack of the oxygen in hipolimnium during summer months. After the elimination following the heavy rains, the hasty increase of the zooplankton numerous was recorded. Abundance of the zooplankton was higher was in shallow parts of the lake in the area of the mouth comparing the sites close the dam. This research has shown that the zooplankton was present in all parts of the lake during entire year, especially in the epilimnion that characterizes with the favourable temperature and oxygen conditions.

The paper presents the results of aquatic macroinvertebrates community analyses of the Moravica river with the aim to evaluate saprobiological status. Sampling were carried out tree localities during 2003 and 2004.

The objective of the paper is establishing of eco-chemical characterization of the river system by investigating and distribution heavy metal content in the river sediments using sequential extraction and total digestion. Heavy metals toxicity and bioavailability in the Danube river sediment are defined according to their distribution between different phases. Sediments samples were taken from 9 sites and analysed for cadmium (Cd), iron (Fe), manganese (Mn), lead (Pb), copper (Cu), zinc (Zn) and chromium (Cr), and the results about cadmium and iron presented in this paper.

The Water Book maintenance is obligated. The electronic form of Water Book and following documents provides an insight into data from issued water acts, in a simple, systematic and arranged way, which enables easy and fast search, according to assigned key, of data extraction and report printing. Program package is provided by Republic Directorate for Water. The implementation of Water Book program is realised in the Ministry of Agriculture, Forestry and Water Management of the Republic of Serbia - Republic Directorate for Water. Public water enterprises and communities that have technical capacities for program installation.