Coastal plant communities of the classes Cakiletea maritimae and Ammophiletea along the Russian coast of the Sea of Azov were classified according to the Braun-Blanquet approach. Three new associations Artemisio santonici–Crambetum maritimae, Artemisio santonici–Leymetum racemosi, Galio humifusi–Crambetum maritimae and two subassociations G. h.–C. m. typicum and G. h.–C. m. medicaginetosum falcatae were established. Tables of the relevés of the new syntaxa and synoptic comparative tables are given.

Population structure and morphological variability of halophilic species Gypsophila paulii Klokov, G. perfoliata L. and G. scorzonerifolia Ser. have been investigated in industrial ecotopes in the south-east of Ukraine and in the region "Prydniprovje". The adaptation processes running in the populations results in predominance of young individuals in the age spectrum and in low correlation and low average variability of morphological characters. In the organism level, the investigated species distinguish by their phenotypic plasticities expressed in compensatory development of vegetative and generative organs. This is shown by absolute values of the features and also by calculated vitality classes of populations and coefficients of divergence and variation.

Classification of the aquatic plant vegetation of the river Ingul is given using the Braun-Blanquet method. We observed four vegetation classes: Lemnetea, Potametea, Bolboschoenetea maritimi and Phragmito-Magno-Caricetea containing 47 associations, 12 unions and 6 orders. The diversities of plant species in Bolboschoenetea maritimi and Phragmito-Magno-Caricetea are higher than in Lemnetea and Potametea.

Ultrastructure of leaf surfaces of Bromus squarrosus L. and B. wolgensis Fisch. ex J. Jacq. f. was examined by SEM. It is shown that their epiderma consists of long, crown, silica cells and stomatal cells. Morphological characters and patterns of these cells are very similar in both taxa. In result, recognition of both species is not supported by the studied micromorphological features.

Differences between spatial and functional positions of lichen and bryophyte associations vs. higher plant communities are shown. We recognized four lichen associations in the lower Dnieper sand dunes: Сladonietum alcicornis  Klement (1953), Xanthoparmelietum pokornyiKhodosovtsev ass. nova, Placynthiello uliginosi-Cladonietum rei Khodosovtsev ass. nova, Cladonietum subulato-fimbriatae Khodosovtsev ass. nova; all belonging to the union Cladonion sylvaticae Klement (1950) from the order Peltigeretalia Klement (1950). One bryophyte association, Syntrichietum ruraliformis Boiko et Khodosovtsev ass. nova, was recognized; it belongs to the union Ceratodonto-Polytrichion piliferi (Waldh. 1947) v. Hübschm. (1967) from the order Polytrichetalia piliferi v. Hübschm. (1975). We consider the stage of stabilization of the substrate as the leading factor in succession of terricolous lichen and moss communities on sand dunes at lower Dnieper. With increasing of stabilization of weathering, lichen and bryophyte communities alternate in the following order: (1) Placynthiello uliginosi-Cladonietum rei; (2) Cladonietum subulato-fimbriatae; (3) Xanthoparmelietum pokornyi; (4) Cladonietum alcicornis. Placуnthiella uliginosa growing on sand dunes forms pyramid-forming or pancake-forming microrelief, which indicate intensities of weathering vs. stabilization.

The summer aspect of myxomycete biota in national nature park “Prypiat’-Stokhid” (Western Polissya) has a high species and taxonomic diversity. 39 species of myxomycetes from 17 genera, nine families and five orders Ceratiomyxales, Liceales, Physarales, Stemonitales and Trichiales were  recorded in alder, hornbeam, oak, mixed, pine forests and spruce plantations in summer 2010. Ceratiomyxa fruticulosa (O.F.) Müll.) T. Macbr. was noted as the most wide-spread species in all studied forest communities, Arcyria cinerea (Bull.) Pers. was only absent in pine forests and Stemonitis fusca was only absent in spruce plantations. Other 36 species have more limited distribution in park forests. Comparison between the slime molds of park “Prypiat’-Stokhid” and Schatsk national nature park (Western Polissya) shows differences in species and taxonomic diversity in both, summer and autumn aspects.

The results of study of 26 strains of green algae from ACKU collection represented by original isolates as well as by subcultures deposited in international collections of strains of the genus Stichococcus Nägeli (including 10 strains deposited as non-authentic culture of nomenclature type of this genus – S.bacillaris Nägeli), are reported. In 18 strains (including 7 strains of S.bacillaris) previously undescribed mucous structures have been founded. There are colonial mucilage, mucous sheath, mucous grains and mucous caps whose presence is inconsistent with the author’s diagnosis of this genus. The presence of mucous structures in most of the represented in international collections strains of the genus Stichococcus confirms the assumption of phylogenetic heterogeneity of this genus at the phenotypic level.

New taxa of bryophytes Syntrichia ruralis (Hedw.) F.Weber & Mohr (Pottiaceae) and Riccia rhenana Lorbeer (Ricciaceae) are described. In the former, the new var. polysporogonica Boikois characterized by having 1–6 sporogones per stem. In the latter, the var. violacea Boiko is distinguished by blue-violet leaves and violet amphigastria.

The article comprises a report from an educational expedition students of Faculty of Biology at Adam Mickiewicz University to the Kherson Oblast, which was possible thanks to the cooperation with Kherson State University. The aim was to get acquainted with the natural peculiarities of the central part of southern Ukraine, inter alia two national reserve Askania Nova Reserve and Black Sea Biosphere Reserve.