Arsenic speciation can be very important in analysis of water, foodstuffs, and environmental samples, besides of total arsenic analysis. Hydride generation atomic absorption spectrometry can be used for speciation analysis based on different hydride generation condition. In our work, we studied effect of L-ascorbic acid like the reaction medium and the prereducing agent.

This study investigates removal efficiency of arsenic species from water on natural and modified sorbent materials. Selective removal of As(III) and As(V) from water was carried out with pure natural materials: bentonite, sepiolite, limonite, pyrolusite and zeolite. Materials most commonly used in water treatment, quartz sand and granular active carbon, were modified by iron coating in order to increase its sorption capacity. For the purpose of comparison, commercial material, granular ferry hydroxide (Everzit As), was investigated under the same conditions. The investigations were performed in batch experiments following the standard experimental methodology. Of all the tested natural materials zeolite exhibited significant sorption capacity: 100 microgram As(III, V)/g. Iron coating increased materials sorption capacity for at least 80%. Iron coated sand and iron coated activated carbon exhibited 340 and 430 microgram As(V)/g respectively.

New locations for the distribution of algae C. corniculata (Phaeophyceae) are presented, with a scope to improve scarce knowledge on phytobenthos of the Montenegrian coast. In the Bay of Boka Kotorska this algae is found on 10 locations and on 3 locations, on depth of 3 m and 5 m, measurements of wet weight and length of primary branches are done. Differences between biomass of algae are note between different depths and different seasons, but between different locations there are no significant differences.

Jegricka water body is part of the Main Drainage Channel System. The whole length of Jegricka (65 km, catchment surface 60.380 ha) is located in south part of Backa, Vojvodina Province. This highly modified water flow has become protected area since 2005 due to its specific natural features - diversity and uniqueness of biotic features, especially for birds and plants. In July 2008 survey of freshwater macroinvertebrates was conducted in order to assess water quality and conservation potential according to biotic characteristics according to conservation criteria within SERCON (System for Evaluating Rivers for Conservation) method. The aim of this paper was to evaluate the importance of macroinvertebrates as indicators of conservation potential of Jegricka water using SERCON. Results of analyses of species composition of freshwater invertebrates fauna showed presence of 12 higher taxonomic groups. Within these groups, 23 families were present at eight RHS river sections along investigated part of Jegricka water body. Togheter with SERCON based conservation criteria for macroinvertebrate, two types of biotic indices Biological Monitoring Working Party (BMWP) and Average Score Per Taxon (ASPT) were calculated in order to assess water quality. Results of the survey showed that Jegricka water body belongs probably to moderately polluted water type according to biotic indices. Results of conservation criteria Naturaless showed that observed and expected faunas are similar. Low values of SERCON family richness criteria based on whole length of water body indicate that Jegricka has low conservation potential, and that adequate rehabilitation measures should be considered in the future.

The paper presents the results of orthophosphate concentration trends in waterflows in Serbia, using the method of non-parametric Mann-Kendal test. Data used for these purposes were provided by Republic Hydrometeorological Service of Serbia (RHMZ), sampled on average once a month for the period 1998-2007. Measuring places are shown on the waterflow map by adequate symbol for the various kind of trend and colour of symbol for the intensity of orthophosphate concentration. Statistical analysis of trends is discussed within the comparative review of methods of linear regression and Mann-Kendall test.

Researches of the Zelengora natural lakes during 2008 were performed in Orlovacko, Kotlanicko and the Lake Donje Bare. Water quality analysis of natural lakes of Zelengora were based on preliminary examination of basic physical and chemical parameters, as well as microbiological parameters. In the scope of biological examinations, phytoplankton, zooplankton and benthic fauna were determined. Due to the lack of data on biodiversity of examined natural lakes and whole area of National park Sutjeska results obtained in this research could only represent the first step toward further examinations, as well as the nature and biodiversity preservation in the Republic of Srpska.

During the period of 2004-2005 ichthyological research on natural waters of Bardaca wetland (Bosnia and Herzegovina) was carried out and the occurrence of 24 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 (rivers Matura and Brzaja) was found to be beta mesosaprobic (the 2nd class of bonity) with saprobic index 2.02 for Marura River and 2.03 for Brzaja River. The obtained results indicate that water quality of this part Bardaca wetland was on satisfactory level for multiple purposes (as a source of water for Bardaca fishpond and in order to sustain ichthyofauna diversity and production.

The Bovan reservoir is built on the river Moravica, near Aleksinac (Serbia), primarily for the purpose of water supply. Investigations were carried out during the period of June 2005 to December 2006, with the aim to determine the quality of water, the composition, spatial and time dynamics of communities of microorganisms. The results showed that according to the total number of bacteria in the water reservoir Bovan fall into the category of clean water by Amrazena (1976). By Kohl (1975), water reservoir Bovan belongs to class 2. Summer-time give maximum water characteristics the 2nd-3rd class. Index T/H varies from category to category moderately contaminated clean water. Values heterotrophs percentage representation in the total number of bacteria indicating the great burden of water organic matter.

The aim of this paper is to present the use data of aquatic macro-invertebrates community, beside abiotic parameters, to define typology and type of specific reference conditions and index of ecological status, to contribute to the establishment of the system of ecological status/potential of surface waters in Serbia. The investigation involves macroinvertebrates as biological elements that have been widely used in implementation of the Water Framework Directive.

This study investigates the effect of pH, temperature, contact time and initial metal concentration on Cu++ ions removal from water solutions, using biomass of Lagenaria vulgaris skin (LV). With higher pH, the efficiency of copper sorption increases and reaches its maximum at pH 7.0. Temperature has negative effect on sorption process due to its exothermic properties. Biosorption efficiency increases with time and reaches equilibium after 40 min. Increasing initial copper concentration gives an increase in biosorbent sorption capacity, and a proportional decrease in treatment efficiency. Obtained results have shown that LV based biosorbent is an efficient and available mean for toxic metal removal from natural and waste waters.