During the parasitological investigations on the gills of 3 cyprinid species from Lake Dojran (the Former Yugoslav Republic of Macedonia), are found 4 monogenean species: in Rutilus rutilus dojranensis are found Dactylogyrus similis and Dactylogyrus suecicus, in Scardinius erythrophthalmus dojranensis is found Dactylogyrus difformis, and in Alburnus alburnus macedonicus is found Ligophorus sp. Prevalence in Rutilus alburnus dojranensis is 40.46%, in Scardinius erythrophthalmus dojranensis is 55.56%, and in Alburnus alburnus macedonicus is the lowest and amounts 2.02%. All monogenean species represents the first record for parasitic fauna of fish species in the Former Yugoslav Republic of Macedonia. Finding of Ligophorus sp. in the fishes of the family Cyprinidae is new to science generally.

Concentrations of nitrate above defined levels for portable water are present in most of the groundwater sources in Velika Morava river alluvion. Some problems exists in Meminac and Kljuc, groundwater sources of Pozarevac town. Some detail investigations were organized in 2002. Survey of groundwater quality in the wide surrounding of Kljuc confirmed some earlier made assumptions about influence of agriculture and sewage water, and their contribution to existing groundwater quality.

Nowadays people increasingly use bottled water for drinking which makes bottling a very profitable business. The aim of this paper is better understanding of physical and chemical properties as well as the contents of dominating ions and microbiological purity of 13 spring waters existing on the territory of Zlatibor region (Serbia, Serbia&Montenegro) which according to its water capacity, its watershed features and good roads availability may be further explored for the purpose of water bottling.

The aim of this work is to confirm water quality of the littoral zone of Lake Ohrid at tourist locations during the tourist season 2002. Water quality is presented through following microbiological and chemical parameters: number of psychrophilic and mesophilic heterotrophic bacteria, urolitic bacteria, most probable number of total coliforms (MPN), indicators for fecal pollution (Escherichia coli, Clostridium perfringens), chlorophyll a, dissolved oxygen, biochemical oxygen demand for five days (BOD5), organic loading and total nitrogen.

This report presents investigation performed as a part of a wider study desined to examine the level of pollution effects on fish in Ohrid lake (The Former Yugoslav Republic of Macedonia). Faunal investigation of the fish Barbus meridionalis petenyi Heck. were carried out at the five localities in Ohrid lake. Microscope analysis of histological preparation of barbel hepatic tissue displayed a dominant presence of granulomatous inflammation on a level of hepatocelular parenchyme and cholangiofibrosis on a level of hepatic bile duck. The analysis did not exhibit any correlation between the granulomatous inflammation and the manifestation of the cholangiofibrous alterations.

Importance of sediments quantity and quality problems addressing to land reclamation canal network in Vojvodina (Serbia, Serbia&Montenegro) are pointed out in this paper. Necessity for sediments monitoring and criteria definition for environmental discharge are drown. Special attention is paid to agricultural land as recipient of these sediments.

In scope of complex physical-chemical and biological examination of water quality of the Bocac lake, the river Vrbas and tributaries Ugar and Crna Rijeka, examinations of phytoplankton and zooplankton were performed during 2002 (March-November). In qualitative structure of phytoplankton 7 division were registered, with 93 taxa from 49 genera in total. In warmer period extreme domination have fire algae (Pyrrophyta). In zooplankton structure (Rotatoria, Cladocera, Copepoda) 78 taxa were registered from 36 genera, with distinct domination of Rotatoria group. According to saprobiological analysis species of olligo- and beta-mesosaprobic character are prevailing.

In this paper investigations of biomass of red head grass Potamogeton perfolitus L. from Lake Ohrid were presented. The material was collected from 2 localities along the Ohrid Lake's coast (Grasnica and Kaneo), where anthropogenic influence is different expressed. The results from the investigations show that there are differences in biomass between investigated localities.

The paper deals with determining the dependence of trihalomethanes forming (chloroform, bromdichlormethane, dibromchlormethane and bromoform) on the contents of natural organic matters from groundwater. The analyses was made bay calculating correlation of trihalomethanes forming potential (THMPF) with UV absorbance and permanganate number as surogates parameters for defining in content NOM in water. These were used to observe the changes in the content of organic matters after coagulation. A good correlation of THMPF, PF chloroform and UV absorbance (254 nm) (coeficient of correlation 0.72 and 0.87) was observed as well as a good with UV absorbance (254 nm) (coeficient of correlation - 0.88) and with PN (coeficient of correlation - 0.80) in coeficient of correlation in bromated trihalomethanes forming.

Every country must to concern the biodiversity of flora and fauna, especially in ecosystems rich with endemic and relict species. Such ecosystem is the Lake Ohrid.