The article presents the results of a comprehensive phytosociological survey of forest vegetation of garden landscapes of the Middle Pobuzhzhia region, including the establishment of its syntaxonomic structure, revealing of the leading factors of differentiation, analysis of vegetation units and studied parks in terms of species richness and diversity. The data for the study were 90 vegetation plots sampled by the authors on the territory of 15 objects (8 parks-monuments of landscape art of state importance, 5 – local importance, one arboretum of state importance, and one landscape reserve of local importance). The data were analysed using modern quantitative methods of phytosociological research in the environment of the Juice software. As a result of the study, seven vegetation units were obtained, six of them were interpreted to the level of association (Salicetum albae, Urticodioicae-Alnetumglutinosae, Chelidonio-Robinietum,Tilio-Carpinetum,Isopyro thalictroidis-Carpinetumand Galeobdolo lutei-Carpinetum) and one as a derivative community. The resulted units represent four classes of vegetation - Salicetea purpureae, Alnetea glutinosae, Carpino-Fagetea sylvaticae and Robinietea. The ordination analysis revealed the ecological separation of the derivative community Taraxacum officinale + Fraxinus excelsior, which combined park phytocenoses with the most intensive management, from other vegetation units, as well as the leading role of moisture and continentality in differentiation of the studied vegetation. A comparative analysis on the level of species richness and values of Shannon-Wiener and Simpson diversity indices showed the dependence of these indicators on landscape diversity, managment intensity and area of studied parks. The highest species richness and diversity was observed for floodplain alder forests of the class Alnetea glutinosae, which are very rare in the studied parks. The results of the study can be a theoretical background for planning the management and reconstruction of garden and park landscapes in the region.

New findings of a rare and endangered species Thalictrum foetidum L. (Ranunculaceae) in the steppe zone of Ukraine are reported. For the territory of the "Buzky Guard" National Natural Park  in the Mykolaiv region, we rediscovered the only known locality from this area in the vicinity of Bogdanivka village. Also, we found a new locality near the Lviv village. In the National Natural Park “Kamianska Sich” we found a new for the Kherson Region and southernmost in Ukraine locality of Th. foetidum. We give the description of these localities, their ecological and syntaxonomical peculiarities. In general, all the localities we found in the steppe zone are characterized by the presence of outcrops as granitic ones on the territory of "Buzky Gard" National Nature Park and limestone outcrops on the territory of "Kamyanska Sich" National Nature Park. All the populations were overgrown with shrubs and were shaded. All of them occurred on steep and medium-steep slopes (20–60°) of the northern and north-eastern exposures. On the territory of "Kamyanska Sich" National Nature Park Th. foetidum grows in communities of the class Festuco-Brometea Br.-Bl. et Tx. ex Soo 1947. In the "Buzky Guard" National Nature Park the syntaxonomic position of Th. foetidum is much more diverse. In addition to steppe communities, it was also found in communities of the class Crataego-Prunetea Tx. 1962, transitional vegetation between Crataego-Prunetea and Festuco-Brometea, as well as in communities of chasmophytic vegetation of classes Asplenietea trichomanis (Br.-Bl. in Meier et Br.-Bl. 1934) Oberd. 1977 and Polypodietea Jurko et Peciar ex Boșcaiu, Gergely et Codoreanu in Rațiu et al. 1966. Th. foetidum in the steppe zone is extremely rare and therefore its populations require further study and application of conservation measures.

A study of the state of preservation of a rare component of the flora of the site on the left bank of the middle reaches of the Dnipro River with an area of 19036,5 hectares, which is the object of the Emerald Network UA0000337 «Divychky». It is proposed to create within this national nature park. Vegetation is represented by meadow-swamp, forest-shrub-swamp and forest biotopes. There are four types of localities are dominant: shallow water areas of ancient lakes and coastal shallow waters with aquatic and coastal-aquatic vegetation; flooded segments of terraced and cavity depressions of the pine terrace with a complex of shrub-forest-meadow-swamp vegetation; lowland plain and slightly hilly segments of the pine terrace with medium-rich fresh sod-podzolic soils with oak and oak groves; uplift segments of aeolian origin with dry poorly formed soils and sands with dry forests, pine forests and psammophilous wastelands. Currently, it can be stated that 6 sozophyte species of international, 13 national and 7 regional significance are growing in the territory of the valley complex of sand terraces Dnipro-Karan. Among the protected species of European importance are populations of 6 species: Iris hungarica, Jurinea cyanoides, Ostericum palustre, Salvinia natans, Liparis loeselii, Trapa natans (the three last belong also to the Red Data Book of Ukraine). Moreover, 10 populations of species from the Red Data Book of Ukraine are registered on the mentioned area: Dactylorhiza incarnata, Daphne cneorum, Epipactis helleborine, E. palustris, Lycopodiellainundata,Lilium martagon, Neottianidus-avis, Platanthera bifolia, Pulsatilla pratensis and Stipa borysthenica.Populations of 14 sozophyte species are represented by many localities with a high number of individuals and good indicators of the reproductive process; 6 species represent poorly due to the small number of localities and low number of individuals in populations; for populations of 3 sozophyte species (Liparis loeselii, Lycopodiella inundata, Dryopteris cristata) there is a danger of extinction due to the fact that only a few localities with a small number of individuals were found. The current state of the landscape complex of this area determines the high probability of growth of some species of sozophytes, which makes further research relevant.

The article provides an annotated list of rare vascular plants from Lower Dnipro sands (Kherson and Nikolaev oblasts), an annotated list of rare flora includes 126 species (14.3% of the total flora) from 99 genera and 54 families. There are one species from European Red List (Agropyron dasyanthum), two species from Red list of the International Union for Conservation of Nature (Salvinia natans), ten species from the Convention on International Trade in Endangered Species of Wild Fauna and Flora (all representatives family Orchidaceae), seven species from the Convention on the Conservation of European Wildlife and Natural Habitat (Bern) (Ostericum palustre, Lindernia procumbens, Zostera marina - only in Bern), thirty-four species from the Red Book of Ukraine (of which: status "Endangered" have 4 species – Alyssum savranicum, Carex liparicarpos, Fimbristylis bisumbellata, Tephroseris palustris, "Vulnerable" – 23 species, "Rare" – 5 species and "Invaluable" – 6 species), forty-one species from the Red List of the Kherson region, seven species from the Red List of the Mykolaiv region. Forty-two species were proposed for including in the Red List of the Kherson oblast (thirty-nine) and forteen species for Red list of the Mykolayiv oblast (only in RLMO – Centaurea odessana, Centaurium spicatum, Moehringia trinervia). Examining chorology of rarity in the arenas, it was found that Kinburn Spit has highest sozological status seventy-two species, including twenty-nine species of vascular plants, which are nowhere else to be found on the Lower Dnieper sands (Crambe maritima, Eringium maritimum, Astrodaucus littoralis). The second place in terms number of rare species is occupied by the Ivanovska arena - fifty-one species, of which twelve species are unique to this arena (Allium regelianum, Salicornia borysthenica, Tulipa gesneriana). Chalbaska arena – forty-six rare species, of which six species are unique to this area (Ostericum palustre, Dactylorhiza majalis, Eremogone rigida). In fourth place is the Oleshkovska arena – forty-five species, ten rare are unique to this area (Carex atherodes, Epipactis palustris, Menyanthes trifoliata). Fifth place is occupied by the Zburyevska arena – thirty-two sozophytes, of which three species are characteristic only of it, namely: Athyrium felix-femina, Dryopteris filis-mas and Tephroseris palustris. Penultimate place is occupied by the Kozacho-Lagerska arena – twenty-six rare species of vascular plants, four sozophytes are characteristic only for this area, namely: Drosera rotundifolia, Nymphaea alna, N. candida and Schoenoplectus mucronatus. Last is Kakhovska arena – fifteen species and only one species is endemic – Doronicum hungaricum, but its location has not been established by the author.

We present new and validated names of some syntaxa of the vegetation class Festuco-Brometea. True steppe vegetation of Eastern Europe, which is distributed from the Eastern part of Romania to the Urals, we propose to consider as a separate order Galatello villosae-Stipetalia lessingianae. It is an intermediate link between meso-xeric communities of the Central and Eastern Europe of the order Festucetalia valesiacae Soo 1947 from one hand, and desert steppe vegetation of the order Tanaceto achilleifolii-Stipetalia lessingianae Lysenko et Mucina in Mucina et al. 2016 from the other hand. We describe a new order Cephalario uralensis-Jurineetalia stoechadifolii for rocky dwarf-shrub calcareous grasslands of the Pontic region. It replaces the order Stipo pulcherrimae-Festucetalia pallentis Pop 1968 in Eastern Europe due to more continental conditions. We validate the name of the alliance Galio campanulati-Poion versicoloris, as well as its type association. This alliance includes rocky grasslands on limestone outcrops from the Central and Western Podillia and belongs to the order Stipo pulcherrimae-Festucetalia pallentis Pop 1968 on the easternmost range of its distribution. We describe a new association of the desert steppes from the Republic of Kalmykia of the alliance Tanaceto achilleifolii-Stipion lessingianae. In addition, we publish the replacement name Paeonio tenuifolii-Stipetum tirsae as a substitute for illegitimate later homonym.

As a result of mycological research 34 species of coprophilous ascomycetes from 14 genera, 10 families, and 5 orders were recorded on the territory of the Oleshkivski Pisky National Nature Park. Among them 15 species belonged to the class Sordariomycetes, 12 – to Dothideomycetes, and 7 – to Pezizomycetes. Among the orders of the fungi, Sordariales – 12 species, Pleosporales – 11, and Pezizales – 7, occupy the leading position; the rest of the orders revealed the fewer number of species. Among the families, Sporormiaceae, Podosporaceae, Coniochaetaceae, Delitschiaceae, and Sordariacea, were the most abundant regarding the number of species and specimens. The species from the five leading families represent 64,7% of the total number of identified species. Among the found genera of the coprophilous ascomycetes, Coniochaeta, Delitschia, Sordaria, Sporormiella, and Triangularia prevailed by number of species, demonstrating much larger diversity, than others. Environmental conditions inside the park are more favorable for the development of loculoascomycetes and pyrenomycetes. The discomycetes species diversity was much less. The list of recorded fungi and their substrates is presented. All species of ascomycetes were collected on the hare and cattle excrements. Other dung types have not been studied. 31 species are new to the territory of the park, 15 species are new records for the steppe zone of Ukraine. Coniochaeta hansenii and Sporormiella tetramera are first recorded in Ukraine. Descriptions, illustrations, synonyms and general distribution are provided for them. C. hansenii is a fairly common and widespread species in the world, occurring mainly on the leporid droppings. In the park, this species was also collected on hare dung. S. tetramera also belongs to the widespread but rare species of coprophilous ascomycetes, known from isolated records in a few countries. It was collected on the hare excrements in the park. Сoniochaeta leucoplaca, Delitshia perpusilla and Triangularia comata were collected for the first time in the steppe zone of Ukraine and for the second time in the country.