On the base of monitoring of water quality for aquaculture, performed since 2010, it is noticed that two positions are showing increased level of trophicity and bacteriological contamination. Changes in sanitary quality of farms are especially intensive during the summer months, so the results of basic physical, chamical and biological parameters, measured during periods June-September 2010 and 2011 are presented and compared.

This paper presents results of measuring the contents of certain bioindicators in samples of digestive gland and lung of mussels (Mytilus galloprovincialis). The results were obtained in the framework of the Program for monitoring ecological status in Montenegro from 2009 to 2011 year. Samples were collected from two locations: Kotor-Dobrota (wild mussels) and the site of Bijela (caged mussels). Dynamic of sampling was twice a year, in April and September. In order to estimate the spatial distribution and temporal trends of pollution the results were compared with analysis of biomarkers in the three localities in the Slovenian coastal waters (bays Piran, Koper and Strujan). Biomarker responses showed no differences between these positions in the southern and northern Adriatic.

Monitoring of ecological condition of the coastal sea of Montenegro has been carried out extensively since 1963 along with foundation of the Institute of marine Biology in Kotor (Montenegro). Recently, in accordance with recommendations of the Barcelona Convention, the LBS Protocol, the EU Framework Directive for coastal waters and domestic laws, in recent years has been carried out continuous monitoring of quality water, sediments, biota as well as ecological effects of pollution on constant monitoring positions in this southeastern part of the Adriatic. In this paper was given an over view of activities and the plan of long-term continuous monitoring of environmental quality and ecological condition of the coastal sea of Montenegro.

The aim of this work is to present the trophic state of water at the pelagic zone of lake Prespa, reviewing the result of defined parameters of physico-chemical and algological aspect. Investigations are done according to standard limnological methods and the samples for analysis were collected from one vertical profile (0, 5, 10 and 15 m) monthly during 2008 year. Water categorization, on the basis of gathered data from analyses of the sampling localities was done according to the OECD-regulations, positive law regulations of the Republic of Macedonia and Nürnberg classification system. Data from this investigating period point out that this area of the lake Prespa is by great influence of the anthropogenic factor and intensive eutrophication.

The aim of this work is to present the water quality of littoral zone of lake Prespa, based on defined physico-chemical parameters (NO3, NO2, NH3, total nitrogen). Samples for analysis were collected with a monthly dynamics during 2007 year (April-December). This period is not chosen by chance, in regard to that the lake basin is constantly under the anthropogenic influence and climate changes that have been registered by this time. According to the obtained results of the performed analyses, basis of the water act of RM and OECD regulation, a categorization of the after was made in the respective measuring points.

Investigation in this study should indicate to importance of aquatic macrophytes in accumulation of toxic metals in aquatic ecosystems and control of their pollution, as well as to establish which plants are well hiperacumulators and test species for remediation, in order to protection, regeneration and conservation of the Gruža lake as reservoir that is important for water supply and as particular natural ecosystem. Obtained results showed that species Lemna gibba L. was reliable indicator of surrounding conditions (environment), as well as good accumulator of heavy metals, so it could be used to remediate aquatic ecosystems.

Processes in the aquatic environment have been intensively explored in recent years, especially sorption processes. In this study, the sorption behavior of benzothiazole (BT) and 2-methylthiobenzothiazole (MTBT) was investigated, on geosorbents with different contents of organic carbon (OC). For both geosorbents and selected organic compounds, nonlinear isotherms were obtained. BT had the greatest degree of nonlinearity on the geosorbent with a higher content of OC, whereas the greatest degree of nonlinearity for MTBT was obtained on the geosorbent with lower OC content. From a comparison of logKoc for selected concentrations, it can be concluded that the geosorbent with the higher OC content has a higher affinity for the sorption of selected compounds.

The paper presents the results of different methods of sequential extraction of metal in sediment of the Great Backa canal in order to obtain data on the total, available and potentially available contents of heavy metals as well as risk assessment in aquatic systems. Based on the results of sequential extraction of metals was found that sediment does not have the risk to the environment in terms of Cr, Cu and Pb concentration while the contents of Ni, Zn and Cd sediment indicates a moderate risk. Results of sequantial extraction of metals indicate that the risk to the aquatic ecosystems decreases in risk assessment based on the pseudo total metal content in the sediment. Thus the results suggest that not all detected metals are bioavailable and that not only on the basis of total metal content of the actual risk may be overestimated.

In the year 2010 ichthyological research on some Vrbas River tributeries located on wider area of Banjaluka city (Bosnia and Herzegovina) was carried out and the occurrence of 14 fish species was recorded. On the basis of the occurrence and abundance of fish species indicators as limnosaprobic parameter, water quality of the analyzed watercourses variated from oligosaprobic to beta mesosaprobic (I and II class of bonity) with saprobic index from 1.27 for Švrakava River to 1.81 for Vrbanja River. The obtained results indicate that water quality of this Vrbas River watershed was on satisfactory level for multiple purposes (in order to sustain ichthyofauna diversity and production and as potential protected areas and spawning zone for some endangered domestic fish species).

In this work, the results of preliminary study of stomach content in brown trout (Salmo trutta L. 1758) of the Gradac in autumn are presented. The fishes were collected by the end of September of 2011 at three sampling sites along the course. A total of 12 fish specimens were examined. By examination of trout stomach content have been found members from macrozoobentho-groups – Trichoptera, Ephemeroptera, Diptera (fam. Ceratopogonidae), Oligochaeta, Coleoptera. At the same time, investigations of bottom fauna composition and structure have been done also. Our study showed that the diet of brown trout is dependent of bottom fauna availability and abundance.