It has been done the analysis of the physical and chemical characteristics of the water from two households in the village Berkovac in the foot of the mountain Maljen, Serbia (Yugoslavia). These households are supplying from two different springs. The water from the spring "Dobracinovica izvor" is contaminated and it is not for use, but the quality of the water from the hill Kulica is satisfactory. Both of them belong to the group of cold mineral waters.

Determination of total organic carbon content (TOC) and trihalomethane formation potential (THMFP) as well as correlation of those two parameters is recommended for monitoring of water bodies which are considered as drinking water resources. Those parameters would enable a categorization of water bodies from the protection point of view as well as from view of their usage as drinking water sources. Relationship between TOC and THMFP is dependent on the origin and the structure of organic matter in water. In this paper the correlation of TOC and THMFP is given for different kind of resources.

MPI - Metal Pollution Index is being proposed with an aim improving the freshwater pollution control, monitoring and classification based on fish metal body burden. This is a simple mathematical model which enables presentation of Cd, Pb, Cu, Zn and Al fish liver concentration as a single value. After thorough studies of bioaccumulation, biomagnification and tissue distribution patterns, liver of Carassius auratus gibelio has been chosen as sentinel organ. Normal distribution and biological variation assessment is being achieved by using normalizers - reference values (liver concentrations of selected elements in fish from reference sites Vruje and Moharac micro water reservoirs, Serbia (Yugoslavia)). Selected representative sites have been evaluated according to new classification of freshwater ecosystem based on MPI values.

The investigations of qualitative and quantitative composition of plankton and the bottom fauna of the Tisza river, Serbia (Yugoslavia), were conducted during 1998. According to the analyses of the indicator species of hydrobionts, saprobic index was calculated, and the estimation of the water quality of the lower flow of the dam near Novi Becej on the structure and abundance of the investigated organisms.

In our previous papers, it is concluded that wood sawdust can be applied as adsorbent for heavy metals removing from water. All earlier investigations are done in batches, while it is confirmed that different heavy metals are adsorbing with various efficacy on sawdust of different kind of wood. Adsorption of copper ions from model water is investigated in this paper, by its passing throw column filled with poplar and fir sawdust, granulation in the range 0.5-1 mm. Starting concentration of copper ions was the same in all experiments, and flowrates of model water and column geometry are varied. Certain volumes of water are taken on the column outlet, and copper ions concentration are determinated in this samples. On the basis of these results breakthrough curves are obtained, and adsorption parameters in dynamic conditions are determinated.

Activities of rat brain synaptic plasma membrane (SPM)Na(+)/K(+)-ATPase and Mg(2+)-ATPase were investigated by in vitro individual and simultaneous exposure to ions of the first transition series metals (Cu(2+), Zn(2+), Fe(2+)). All investigated metals produced a larger maximum inhibition of Na(+)/K(+)-ATPase than Mg(2+)-ATPase activity. Metal concentrations causing 50% inhibition of Na(+)/K(+)-ATPase activities were: Cu(2+) 7.1 microM Zn(2+) 19 microM Fe(2+) 25 microM. Simulataneous exposure to metal combinations: Cu(2+)/Zn(2+), Cu(2+)/Fe(2+) and Zn(2+)/Fe(2+) inhibited both the Na(+)/K(+)-ATPase and Mg(2+)-ATPase activity synergistically, i.e., more than the sum of the metal induced inhibitions assayed separately. It is also established that the plot of logarithm IC50 values of Na(+)/K(+)-ATPase activity vs. the ionic radius of (Cu(2+), Zn(2+), Fe(2+)) is a straight line that enables to predict the value IC50 for other metals of the first transition series. The results obtained show that Na(+)/K(+)-ATPase is promising as a biological component of biosensor.

Base characteristic melioration territory "Upper Danube" inclusion round about 1.4 million ha area in Backa and Banat (Serbia, Yugoslavia) are presented in this paper. Specification problem maintenance of the drainage of system to originate because of discharge wastewater and sludge in channel and suggest in decides these problems are considered.

Upon the construction and introduction of overflow lagoons for gravitational precipitation, starch production plant wastewater drained into the river (channel) Nadel, satisfy quality conditions established for irrigation of crops which bare waters with high salinity.

In this paper, some data on long term seasonal investigation of hydrography and plankton are presented. The most important fact is that the whole area is exposed to the impact of the freshwater from numerous sources from the coast and submarine springs in Boka Kotorska Bay, as the impact of rivers Bojana and Drim. Exchange of the intermediate water-masses between Adriatic and Jonian basins is of great importance, too. So, basic ecological data, as well as characteristic phytoplankton and zooplankton groups and species are described.

In the late sixties and early seventies the processes of intensive erosion prevailed in the catchment and channel of the torrent Lonjinski Potok, Serbia (Yugoslavia). As the consequence the village Lonjin and the very important road Belgrade - Loznica - Uzice, Serbia (Yugoslavia). In the period 1973-1980, significant erosion control works (ECW) were performed in the watershed and in the channel of the Lonjinski Potok torrent. As the results of this the processes of low erosion occur in the watershed and sediment transport is under limit of the runoff regime. Now, runoff regime is balanced without the floods and long drought period. According his quality water belongs to the first classe. Results of research shows that erosion control works are, also, very important factor for balanced runoff regime and water quality.