Mirko Cvijan

Distribution of phytoplankton community in Kotor Bay (south-eastern Adriatic Sea)

The goal of this paper was to explain variability of phytoplankton in a shallow coastal area in relation to physico-chemical parameters. Temporal variability and composition of phytoplankton were investigated in the Kotor Bay, a small bay located in the south-eastern part of the Adriatic Sea. Samplings were performed weekly from February 2008 to January 2009 at one station in the inner part of the Kotor Bay, at five depths (0 m, 2 m, 5 m, 10 m, 15 m). Phosphates, nitrites and nitrates ranged from values under the level of detection to the maximum values of 1.54, 1.53 and 23.91 µmol l−1, respectively. The phytoplankton biomass — represented by chlorophyll a concentration — ranged from 0.12 to 6.78 mg m−3, reaching a maximum in summer. Diatoms were present throughout the whole sampling period, reaching the highest abundance in March (3.42×105 cells l−1at surface). The peak of dinoflagellates in July (2.2×106 cells l−1 at surface) was due to a single species, Prorocentrum micans. The toxic dinoflagellate Dinophysis fortii occurred at a concentration of 2140 cells l−1 in May. The present results of phytoplankton assemblages and distribution provide valuable information for this part of the south-eastern Adriatic Sea where data is currently absent.

A Checklist of Desmids (Conjugatophyceae, Chlorophyta) of Serbia. II. Genus Cosmarium

Abstract The desmid flora of Serbia has been surveyed during various periods. The first data on the distribution of desmids in Serbia date back to 1883 and from then on until 2009 altogether 630 different taxa were identified. Among 23 genera of desmids in all, the most diverse and most commonly found is Cosmarium (242 taxa or 38.4% of the total number of taxa). Taxa belonging to the genus Cosmarium grow in distinctly diverse habitats, from lowland rivers to high-mountain peat bogs. The present paper gives a survey of the major taxonomic and ecological characteristics of the Cosmarium taxa which have been identified in Serbia. The present studies regarding the distribution of Cosmarium taxa over the territory of Serbia, show that extremely rare, very rare and rare taxa comprise 96.3% of all recorded Cosmarium taxa. The species Cosmarium botrytis, C. laeve, C. meneghinii and C. subprotumidum appear widely distributed in the territory of Serbia. High-mountain peat bogs are characterized by the greatest diversity of the Cosmarium taxa.

Desmids of vlasinsko lake — from peat bog to lake

Summary The investigation of the floristical composition of algae in Vlasinsko lake was done in August, 1989. In this paper special attention is given to the desmids as one of the most abundant and heterogenous group of algae in todays lake as well as in the once existed peat bog. The authors followed the successive changes in the desmids composition in the passed period of 83 years: at the time when the peat bog had existed, as well as during the formation of Vlasinsko lake, to the time when the lake has been formed. Considerable increase in the number of the once peat bog desmids and the presence of 28 new taxa was observed. The presence of a large number of floating peat islands, especially in the shallow, southern part of the lake noticed in 1989, contributes to the hypothesis of regeneration of peat bog.

Some new and interesting ecological observations on desmids from the Province of Vojvodina (Northern Serbia)

A detailed qualitative investigation of the desmid community in the territory of the Province of Vojvodina (Northern Serbia, part of the Pannonian Plain) revealed a surprisingly high number of desmid taxa. Although most of the desmids were marked as rare, according to the results of physico-chemical analyses of water samples, several taxa were frequently recorded in habitats that are generally deemed unsuitable for desmids. The ecological characteristics of 18 desmid taxa, some of which known as acidophilic and/or oligotrophic, are briefly discussed. The unexpected presence of many desmid taxa is explained by assuming that their tolerance threshold to various physico-chemical parameters has changed considerably.

High tolerance to water pollution in Cosmarium boitierense Kouwets and Staurastrum bloklandiae Coesel et Joosten, taxa recorded for the first time from the Balkan Peninsula

Detailed investigations into the desmid flora of the Province of Vojvodina (north Serbia) were performed in the period from April 2002 to May 2003. Although water of the investigated localities was marked as alkaline, distinctly hard, enriched with mineral salts and organic, biodegradable compounds, a surprisingly high number of desmid species was recorded. Two taxa, Cosmarium boitierense var. boitierense and Staurastrum bloklandiae, are new to the algal flora of Serbia as well as for the Balkan Peninsula. In this paper 47 plankton samples from six localities holding these taxa are taken into consideration. It was found that Cosmarium boitierense var. boitierense and Staurastrum bloklandiae are inhabitants of eutrophic and alkaline freshwater ecosystems containing a considerable amount of mineral salts, toxic compounds, heavy metals and s-radioactivity.

Algal Communities Along the Sava River

Field analysis of phytoplankton and phytobenthos communities of the river Sava has been performed, from Slovenia to Serbia, in August 2011 and September 2012 at 20 localities. A total number of 256 taxa have been determined, from eight divisions: Cyanobacteria (20), Rhodophyta (1), Dinophyta (6), Cryptophyta (1), Chrysophyta (1), Bacillariophyta (152), Chlorophyta (67) and Euglenophyta (8). In the phytoplankton samples, 188 taxa have been identified and in the phytobenthos samples 153 taxa. The most diverse divisions of phytoplankton of the river Sava were Bacillariophyta (46.28 % of total taxa number) and Chlorophyta (34.57 % of total taxa number). Biomass of phytoplankton was low, and the abundance of phytoplankton communities varied between 65,000 and 412,000 Ind L−1. The biomass of phytoplankton of the river Sava was in the range of 41 to 564 μg fr. wt. L−1. The phytobenthos dominated by the division of Bacillariophyta, making 81.7 % of the community. Visible macroaggregations were composed of Cladophora glomerata (Chlorophyta) and Thorea hispida (Rhodophyta).

Three new records for diatoms from the Nišava River and its tributary, the Jerma River (Southern Serbia)

The main objective of this paper is to report three benthic diatom species from the Nišava and Jerma Rivers, which prove to be new findings in the context of the Serbian diatom flora. These are also new distributional records for all three species. Monthly samples (from stones, sediments and macrophytes) were collected from May 2008 to May 2009. Diatom frustules were cleaned using chemical agents, and mounted on permanent slides. Descriptions (main valve measurement of the populations in the Nišava and Jerma Rivers), ecology, distribution in Serbia and Europe, and appropriate photomicrographs of three species are presented. Navicula novaesiberica Lange-Bertalot and Neidiomorpha binodiformis (Krammer) Lange-Bertalot & Cantonati are rarely found in Europe, while Parlibellus protracta (Grunow) Witkowski is more common. Navicula novaesiberica and Neidiomorpha binodiformis were found at higher water temperatures in comparison to temperatures reported in the existing literature. These new taxa significantly contribute to diatom floristic richness of the Nišava and Jerma Rivers in Serbia.

A Checklist of Desmids (Conjugatophyceae, Chlorophyta) of Serbia. III. Genus Staurastrum

Abstract The first data about the distribution of desmids in Serbia derive from the year 1883 and from that time up to the end of 2010 there were identified 646 different taxa. The species-rich genus Staurastrum is represented with 116 taxa which is about 18% of the total number of desmids in Serbia. Taxa of the genus Staurastrum occur in a large variety of habitats in Serbia, but the greatest diversity was recorded in high mountain peat bogs. In Serbia till now, a large number of taxa of the genus Staurastrum (40.5%) has been found only on one locality (exceptionally rare taxa). In contrast, the species S.alternans, S. gracile, S. orbiculare, S. paradoxum, S. polymorphum and S. tetracerum belong to the most common species in Serbia. In this paper a review is presented of the main taxonomic and ecological characteristics of taxa of the genus Staurastrum, recorded from Serbia.

DesmiD flora (Chlorophyta, ZygnematophyCeae) of the Danube in the provinCe of vojvoDina (northern serbia)

This paper presents results of a detailed investigation into the qualitative composition of the desmid flora of the Danube performed from April of 2002 to May of 2003. A total of 70 desmid taxa belonging to four genera were recorded. Forty-seven taxa are new to the Vojvodina stretch of the Danube, while Cosmarium kjellmanii, Staurastrum bloklandiae, and S. smithii are taxa new to the algal flora of Serbia. Qualitative dominance of desmid taxa typical of alkaline and eutrophic ecosystems was observed. The qualitative composition of planktonic taxa, their quantitative composition, and regular seasonal dynamics of the desmid community were analyzed in the relation to physico-chemical characteristics of the water. Water quality was analyzed on the basis of desmids, which are bioindicators. The partly unexpected presence of certain desmid taxa, i.e., several typical acidophilous species, alpine forms, and/or taxa characteristic of oligotrophic water was recorded.