Сибирский экологический журнал, 3 (2016) 390404 УДК 574.5 DOI 10.15372/SEJ20160310 Vegetation of the Hydrochari-Lemnetea and Potametea classes in the Danube-Tisza-Danube hydrosystem (Serbia) 21000, Serbia, Novi Sad, Trg Dositeja Obradoviжa, 8 E-mail: branа@polj.uns.ac.rs D. DIGURSKI, Lj. <...> NIKOLIЖ, B. LJEVNAIЖ-MAIЖ Faculty of Agriculture University of Novi Sad Статья поступила 20.10.15 Принята к печати 02.12.15 ABSTRACT Aquatic vegetation of Hydrochari-Lemnetea and Potametea classes in the Danube-Tisza-Danube hydrosystem (Hs DTD) was studied in 20092012, by applying the standard Braun-Blanquet method. <...> The canal network vegetation comprises 14 associations, with Trapetum nаtantis and Ceratophylletum demersi being the most widely distributed. <...> Hs DTD is also a habitat for several important endangered species, which serve as edificators of the following phytocenoses: Nymphaeetum albae, Nymphaeetum albo-luteae, Nymphoidetum peltatae, Trapetum nаtantis, Lemno-Spirodeletum, Salvinio-Spirodeletum polyrrhizae, LemnoUtricularietum vulgaris, Potametum nodosi, Myriophyllo-Potametum and Najadetum marinаe. <...> In the studied vegetation, we also found an invasive phytocenosis Elodeetum canadensis that did not have an expanding tendency, and Ceratophyllo demersi-Vallisnerietum spiralis that had this tendency, which made monitoring its stands necessary. <...> Physico-chemical analyses of water, conducted at localities in which the studied phytocenoses thrive, revealed that the development and distribution of most phytocenoses is closely linked with specific habitat conditions. <...> Due to the dense water flow network and unfavourable water characteristics, it was necessary to regulate the water flow regimen, ©Digurski D., Nikoliж L., Ljevnaiж-Maiж B., 2016 390 which was achieved by the development of the Danube-Tisza-Danube hydrosystem (Hs DTD). <...> However, the canal network development resulted in successive disappearance of many marshes and swamps, together with specific aquatic and semiaquatic vegetation. <...> In addition to the findings of numerous studies confirming that macrophytes are reliable indicators of the trophic status and other hydro-chemical parameters [Papastergiadou, Babalonas, 1993; Szaсkowski, K³osowski, 1999; Janauer, Dokulil, 2006; K³osowski, 2006; Otahelovб et al., 2007; Pe³echaty, 2007; Koиiж et al., 2008; Grоnberga, Spriтмe, 2008; Schneider, 2009 <...>