Chara baueri is one of the rarest charophytes worldwide. It had been considered extinct in Europe for more than a century, from the 1870s to 2006, when it was rediscovered in Germany. The current distribution of this species is limited to a few localities in Europe (Germany, Poland and Russia), and one locality in Asia (Kazakhstan). We present a new finding of Chara baueri, to be a significant contribution to the species ecology and biogeography, and helping to review and update the current scarce knowledge. Chara baueri was discovered in Serbia and monitored for two vegetative seasons in 2018 and 2019, along with the associated macrophyte vegetation and water quality parameters. The morphology and ecology data of the species are presented comparatively with the literature data and the biogeography is critically reviewed. The population in Serbia is the first verified record of Chara baueri in southern Europe. Considering the recent findings and the knowledge accumulated in these records, Chara baueri was very possibly never extinct at all, but overlooked in Europe for the entire 20th century. We suggest that waterfowl migrating from the northern parts of Europe should be considered as the important spreading agent of Chara baueri in southern regions.

Various studies report contrasting results on the substrate-type effect on diatom community composition, but the particularly important question is whether or not it affects diatom-based assessments of water quality. We investigated whether the substrate type is a significant predictor of the diatom community composition and if it affects lake water quality assessment based on diatom indices. This study took place in Sava Lake (Serbia). We used glass, ceramic, willow and yew tree tiles as artificial substrates for periphyton development, and pebbles from the lake littoral as natural substrate. Results revealed differences in both the diatom community composition and diatom indices values related to the substrates. A distinction was recognized between natural, artificial wooden, and artificial inert substrates. However, the final lake quality assessment based on diatom indices was more or less similar in all substrate types in our study, and depended on value ranges associated with water quality classification and on diatom index choices. Artificial substrates in our study did show potential as an alternative for natural substrate, but further studies are required, particularly in various types of lentic ecosystems to confirm our findings and support artificial substrate employment in lake water quality assessment.

U radu je prikazano tretiranje otpadne vode Fenton-sličnim procesom primenom nano nula valentnog gvožđa kao katalizatora. Uzorak otpadne vode generisane nakon štampanja cijan bojom uzet je iz flekso štamparije koja se nalazi u Novom Sadu. „Zelena” sinteza nanomaterijala je sprovedena korišćenjem opalog lišća sa drveta hrasta koje raste u Nacionalnom parku Fruška Gora. Ispitivanje efikasnosti obezbojavanja vodenog rastvora grafičke boje vršeno je serijom eksperimenata na aparaturi za JAR test.

Directeur De la publication / Publication director : Bruno DAVID Président du Muséum national d'Histoire naturelle réDactrice en chef / editor-in-chief : Line le Gall Muséum national d'Histoire naturelle assistante De réDaction / assistant editor : Chris LE COQUET-LE ROUX