Academic literature on the topic 'Vegetation classification Plant communities Floodplain plants Floodplain ecology'

The distribution of vegetation communities on floodplains within Kakadu National Park, in tropical northern Australia, is related to micro-topography and, therefore, water depth and duration of flooding. Floodplains of the Kakadu Region, because of their proximity to the coast, are most vulnerable to the impacts of climate change, with saltwater intrusion, as a result of sea-level rise, being a serious risk. Our main objectives were to determine the variability of the distribution of plant communities on the floodplains and understand the potential risk of increased saltwater intrusion to these communities. We present data on the natural salinity-tolerance range of selected floodplain plants and discuss the likely effects of saltwater intrusion on floodplain plant distributions and productivity. The results of change analysis using high spatial-resolution satellite data showed the importance of the variation of water availability in determining patterns of plant communities. Hydrodynamic modelling suggests that sea level rises will result in 40% of the floodplain transformed into saline habitats by 2070. The most obvious effect of this would be the conversion of the freshwater vegetation to salt-tolerant mangroves and other salt-marsh plants, with a concomitant change in animals and their use of these areas.

Gene flow is a key evolutionary driver of spatial genetic structure, reflecting demographic processes and dispersal mechanisms. Understanding how genetic structure is maintained across a landscape can assist in setting conservation objectives. In Australia, floodplains naturally experience highly variable flooding regimes that structure the vegetation communities. Flooding plays an important role, connecting communities on floodplains and enabling dispersal via hydrochory. Water resource development has changed the lateral-connectivity of floodplain-river systems. One possible consequence of these changes is reduced physical and subsequent genetic connections. This study aimed to identify and compare the population structure and dispersal patterns of tangled lignum (Duma florulenta) and river cooba (Acacia stenophylla) across a large inland floodplain using a landscape genetics approach. Both species are widespread throughout flood prone areas of arid and semiarid Australia. Tangled lignum occurs on floodplains while river cooba occurs along rivers. Leaves were collected from 144 tangled lignum plants across 10 sites and 84 river cooba plants across 6 sites, on the floodplain of the lower and mid Lachlan River, and the Murrumbidgee River, NSW. DNA was extracted and genotyped using DArTseq platforms (double digest RADseq). Genetic diversity was compared with floodplain-river connection frequency, and genetic distance (FST) was compared with river distance, geographic distance and floodplain-river connection frequency between sites. Genetic similarity increased with increasing floodplain-river connection frequency in tangled lignum but not in river cooba. In tangled lignum, sites that experience more frequent flooding had greater genetic diversity and were more genetically homogenous. There was also an isolation by distance effect where increasing geographic distance correlated with increasing genetic differentiation in tangled lignum, but not in river cooba. The distribution of river cooba along rivers facilitates regular dispersal of seeds via hydrochory regardless of river level, while the dispersal of seeds of tangled lignum between patches is dependent on flooding events. The genetic impact of water resource development may be greater for species which occur on floodplains compared with species along river channels.

The studies of natural forest vegetation of Salavat town were made during 2008–2011. 31 relevés of forest communities within the natural boundaries of phytocenoses were done. Vegetation of Salavat town includes ruderal, grass (meadow, steppe, helophyte and water vegetation) and forest vegetation. Water, helophyte, synanthropic, natural and semi-natural grass vegetation of the town was discussed in previous articles (Golovanov et al, 2011 and others). This article is devoted to the syntaxonomy of natural forest vegetation of Salavat town. Syntaxonomy of natural forest vegetation of Salavat town includes 3 classes (Querco-Fagetea Br.-Bl. et Vlieger in Vlieger 1937, Salicetea purpureae Moor in 1958 and Alnetea glutinosae Br.-Bl. et Tx. ex. Westhoff et al., 1943), 3 orders (Fagetalia sylvaticae Pawłowski, Sokołowski et Wallisch 1928, Salicetalia purpureae Moor in 1958 and Salicetalia auritae Doing 1962), 4 alliances (Alnion incanae Pawłowski, Sokołowski et Wallisch 1928, Salicion albae Soó 1930, Salicion triandrae T. Müller et Görs 1958, Salicion cinereae T. Müller et Görs ex Passarge 1961), 4 associations (Alnetum incanae Lüdi 1921, Salici-Populetum (R. Tx. 1931 ) Meijer Drees 1936, Salicetum triandro-viminalis Lohmeyer 1952, Salicetum pentandra-cinereae Passarge 1961) and 5 variants (ass. Alnetum incanae — variant Galium aparine; ass. Salici-Populetum — variants Carex acuta, Bromopsis inermis, Carex praecox and Acer negundo). Plant communities of the class Querco-Fagetea combine the broadleaf and coniferous-deciduous mesophytic forests of the temperate zone of the western Palearctic (Ermakov, 2012). One variant Galium aparine of ass. Alnetum incanae was registered in Salavat town. This variant of the association was described from the urban areas. The presence of synanthropic species such as Acer negundo, Arctium lappa, Arctium tomentosum, Artemisia vulgaris, Chelidonium majus, Convolvulus arvensis, Galium aparine, Geum urbanum, Leonurus quinquelobatus and etc. is very typical. Plant associations represent forests with Padus avium, which are often found in the floodplain of the river Belaya on the rich short-time flooded soils. The class Salicetea purpureae includes both riverine floodplain forest and shrub communities (Yamalov et al., 2012). 2 associations (Salici-Populetum and Salicetum pentandra-cinereae) and 4 variants (Carex acuta, Bromopsis inermis, Carex praecox and Acer negundo) were distinguished. The plant communities of associations Salici-Populetum and Salicetum triandro-viminalis represent the floodplain willow-poplar forests and shrubby vegetation, which are commonly found in the Republic of Bashkortostan on the river banks and lakeshores. Typically the communities are found on the banks of the river Belaya within the town of Salavat (Khaziakhmetov et al., 1989). A distinctive feature of the communities is a presence of the North American invasive neophyte species Acer negundo. Naturalization of this species takes place on the floodplains of the Republic of Bashkortostan. The similar community was recorded in Bryansk region (Bulokhov, Kharin, 2008) and they were described as the association Aceri negundi–Salicetum albae Bulokhov et Charin 2008. Our communities are different due to the dominance of Populus nigra with insignificant role of Salix alba. Further data collection can help to describe the new unit of the ecology-floristic classification. The plant communities of the class Alnetea glutinosae combine the lowland eutrophic black alder swamps, birch swamp forests and thickets of willow shrubs on peaty soils (Ermakov, 2012). The association Salicetum pentandra-cinereae was described. The association represents of hygrophyte and mesohygrophyte communities with dominance of grey willow. These communities are found on the banks of fens and oxbows in abundant moisture conditions. They are rarely found on fen mires in Salavat town.

The present study continues a series of publications of the authors on diversity of the meadow vegetation in the floodplains of the Vychegda and Pechora rivers and their tributaries (Komi Republic). The floristic classification of wet meadows of the order Molinietalia Koch 1926 was published early (Shushpanikova, Yamalov, 2013). The results of floristic classification of meadow vegetation belonging to the order Arrhenatheretalia R. Tx. 1937 are discussed in this article. Analysis was based on 383 original relevés of the meadow vegetation of the order Arrhenatheretalia made in accordance with principles of the Braun-Blanquet approach (Braun-Blanquet, 1964; Mirkin and Naumova, 1998). The studies were performed in the floodplains of the Vychegda and Pechora rivers and their tributaries (Sysola, Kazhym, Pozheg, Viled, Usa, Colva, Synya, Sebys, Ilych, Syuzyu, Shchugor). The descriptions were conducted at the study plots of 10×10 m. Plant communities of small size were described within the natural limits. A location, dimensions of community, species composition, species saturation, composition of dominant and co-dominant species, total coverage and height of grass stand, aboveground phytomass production were identified. The abundance of species in meadow communities was recorded using the J. Braun-Blanquet method: r — species occurs sporadically, + — minor species, total coverage less than 1 %, 1 — 1–5 %, 2 — 6–25 % 3 — 26–50 %, 4 — 51–75 %, 5 — 76–100 %. The assessment of environmental parameters was performed by ecological methods of L. G. Ramensky (Ramensky et al., 1956). Syntaxonomic diversity of the meadow vegetation of the order Arrhenatheretalia of the Vychegda and Pechora rivers floodplains presented by 2 unions (Cynosurion R. Tx. 1947 и Festucion pratensis Sipaylova et al. 1985), 7 associations (Festucetum ovinae Turubanova 1986, Festuco pratensis–Deschampsietum caespitosae Turubanova 1986, Anthoxantho odorati–Agrostietum tenuis Sillinger 1933, Festuceto pratensis–Dactyletum glomeratae Dymina 1989 in Korolyuk et Kiprijanova 1998, Amorio repens–Poetum pratensis ass. nov., Equiseto arvensis–Elytrigietum repentis Maraculina 2009, Elytrigio repentis–Bromopsidetum inermis Yamalov 2011. Two new communities without rank are described (Agrostis vinealis, Hypericum maculatum–Phleum pratense). Most plant associations are heterogeneous by their floristic composition and they can be divided into 10 subassociations and 5 variants. The peculiarities of the floristic composition of the above mentioned associations, as well as their distribution and ecology are discussed. The distinguished associations are well differentiated by their elevation level on the floodplains. The meadow communities of Festucetum ovinae are located on the highest floodplains in the inland zone; there is Agrostis vinealis in the streamside zone of the floodplains. The meadow communities of the ass. Anthoxantho odorati–Agrostietum tenuis are located on the low floodplains in the streamside zone. The meadow communities of the associations Festuco pratensis–Deschampsietum caespitosae, Equiseto arvensis–Elytrigietum repentis, Elytrigio repentis–Bromopsidetum inermis, Festuceto pratensis–Dactyletum glomeratae are occupied the medium level floodplains. The meadow communities of the ass. Amorio repens–Poetum pratensis are found at different locations of the floodplain; they are formed under grazing. The described meadows grow on the soils with different ecological indicators. The distinguished associations are differentiated by water level (52.2–73.0), average figures — 55.9–68.9. The meadow communities of the ass. Festucetum ovinae occupy the driest sites of the floodplain; the ass. Anthoxantho odorati–Agrostietum tenuis is located in the wettest floodplains. The meadow communities of the ass. Elytrigio repentis–Bromopsidetum inermis occupy most rich and alluvial soils. They are located on the low ridges in the middle zone of the floodplain and they are formed by annual flooding on alluvial deposits. The distinguished associations are differentiated by pH (4.2–8.0), average figures — 4.9–7.0. The meadow communities with Agrostis vinealis are occupied the most acidic soil. The meadow communities of the ass. Anthoxantho odorati–Agrostietum tenuis are located on the neutral soils. The meadow communities of the most of associations occupy slightly acidic soils. The variability of moisture varies from alternating values to high values. The greatest differences in moisture are demonstrated by the communities of associations Equiseto arvensis–Elytrigietum repentis and Elytrigio repentis–Bromopsidetum inermis located on middle manes on low and medium levels of the floodplains. The associations are differ by the scale of pasture digression in range 3.3–5.0, average figures — 3.8–4.9. The meadow communities with Agrostis vinealis have the highest rates of pasture digression (4.5–5.1). The meadow communities of the ass. Anthoxantho odorati–Agrostietum tenuis have the smallest ones (3.5–3.9). A comparison of species composition of the syntaxa in Komi Republic with communities described in other regions of the Eastern Europe and the Asian part of Russia was carried out. It was shown that the meadow communities of the Komi Republic have low species diversity. Species richness of meadow communities is less than 39 species on trial area. The meadow communities of the ass. Festuco pratensis–Deschampsietum caespitosae are the richest. 195 vascular plant species are recorded in 213 geobotanical descriptions of the order Arrhenatheretalia. The aboveground phytomass varies from 20–40 g/m2 (Festucetum ovinae) to 520 g/m2 (Festuco pratensis–Deschampsietum caespitosae).

Работа посвящена изучению лугов Нижнего Приамурья. Приводится характеристика данной территории, согласно климатическому районированию Хабаровского края, указываются почвы, на которых формируются луговые сообщества, по А.П. Тильба представлена классификация луговых сообществ по условиям пойменного режима реки Амура, разделяя их на три уровня - высокий, средний и низкий со своими характерными для каждого уровня типами растительности. Рассмотрен растительный покров луговых сообществ каждого уровня поймы Амура. Указываются редкие виды растений, обнаруженные в результате изучения лугов. Для них приведены меры охраны, которые сводятся к включению их в Красные книги Российской Федерации: Dioscorea nipponica, Lilium callosum (2008) и Хабаровского края: Dioscorea nipponica, Lilium callosum, Potentilla freyniana (2019), к обитанию на заповедных территориях: государственного природного заповедника «Большехехцирский», природного парка «Шереметьевский», национального парка «Анюйский», природных парков «Хосо», «Вяземский», государственных природных заказниках «Хехцирский», «Чукенский», «Бирский», «Матайский» и контролю за состоянием популяций этих видов, ограничение сбора заготовок корневищ Dioscorea nipponica до полного запрета в местах интенсивного использования. Here we report the results of the study of meadows of the Lower Priamurye. We characterize the territory according to climatic zoning of the Khabarovsk Region. The soils on which the meadow communities are formed, are noted. According the the classification by A.P. Tilba we present a classification of meadow communities under different flood regimes of the Amur River - high, medium and low. The vegetation of meadow communities at each level of the Amur floodplain is considered. Rare plant species found are reported. Security measures are proposed. Anomg them is an inclusion of the following plants to the Red Data Book of the Russian Federation: Dioscorea nipponica, Lilium callosum (2008), and to the Red Data Book of the Khabarovsk Region: Dioscorea nipponica, Lilium callosum, Potentilla freyniana (2019). They also must be protected withing the protected areas: State Nature Reserve "Bolshekhekhtsirsky", Natural Park "Sheremetevsky", National Park "Anyuisky”, Natural Parks "Hoso", and "Vyazemsky", State Nature Reserves "Khekhtsirsky», "Chukensky", "Birsky", "Mataisky". Populatoins of the mentioned species must be monitored. The collection of rhizomes of Dioscorea nipponica should be diminished up a complete ban.

In the Murmansk Region floodplain meadows of class Molinio-Arrhenatheretea Tx. 1937 being there on the northern limit of distribution in Europe, rarely occur along the large rivers. The research with purpose of classification was conducted in lower stream of the Varzuga River, which is one of the largest (254 km long) river on Kola Peninsula. Few large islands are disposed in the lower course of the river. Riverbanks are formed mainly by sandstones and moraine deposits which prevent the formation of a vast floodplain formation; its the largest area is situated downstream the Varzuga village, that is one of the oldest settlements of Kola Peninsula, arisen in 15 century. The agriculture period on floodplains around the village has about 500 years of regular mowing and grazing. The river basin is located in the taiga zone. Adjacent spruce and pine forests belong to associations Empetro–Piceetum obovatae (Sambuk 1932) Morozova 2008 and Cladonio arbusculae–Pinetum sylvestris (Cajander 1921) K.-Lund 1967, bogs — to ass. Empetro–Sphagnetum fusci (Du Rietz (1921) 1926) Dierssen 1982. Ferns and tall herbs dominated birch forests occur on Varzuga River islands. Sandy beach vegetation of Ammophiletea Br.-Bl. et Tx. ex Westhoff et al. 1946 and halophytic marshes of Junceteamaritimi Br.-Bl. in Br.-Bl. et al. 1952 were described in the river mouth (Koroleva, 1999; Koroleva et al., 2011). Floodplain meadows (Fig. 1) were studied on the river banks and on islands from the Varzuga village to river mouth, in July and August in 2013 and 2015. 46 relevés were performed on sample plots mainly 10×10 m on the base of Braun-Blanquet approach. The syntaxa of high level are in accordance with latest survey by L. Mucina et al. (2016). Floodplain meadows belong to the alliance Astragalo subpolaris–Festucion rubrae all. nov. hoc loco (holotypus — Anthoxantho alpini–Geranietum sylvatici ass. nov. hoc loco) (Table 1) with following diagnostic species: Sanguisorba polygama, Dianthus superbus, Astragalus subpolaris, Oxytropis sordida, Myosotis asiatica, Veratrum lobelianum, Hedysarum arcticum, Senecio nemorensis, Allium schoenoprasum, Potentilla crantzii. Plant communities include mesophytic herbs, diagnostic species of classes Molinio-Arrhenatheretea and Mulgedio-Aconitetea Hadač et Klika in Klika et Hadač 1944, with group of species characteristic for tundra meadows (Dianthus superbus, Astragalus subpolaris, Oxytropis sordida, Bistorta vivipara and Potentilla crantzii). More than half of diagnostic species of alliance Astragalo subpolaris–Festucion rubrae have arctic, arctic-alpine and hypoarctic distribution. Two associations belong to this alliance: ass. Diantho superbi–Festucetum ovinae ass. nov. (Table 2; holotypus hoc loco — relevé 2 (186/13), Fig. 2) with diagnostic species Dianthus superbus, Thymus subarcticus, Campanula rotundifolia, Antennaria ­dioica, Calluna vulgaris, Festuca ovina, Nardus stricta, Viola canina, Potentilla crantzii, P. erecta, Sonchus arvensis, Pilosella laticeps. Low-herb meadows, being used as a pasture, occur mainly on higher and dryer habitats, than the next association. Ass. Antho­xantho alpini–Geranietum sylvatici ass. nov. (Table 3; holotypus hoc loco — relevé 17 (136/13), Fig. 3) includes regularly mowed tall-herb meadows formed after deforestation. Diagnostic taxa are Anthoxanthum alpinum, Geranium sylvaticum, Angelica sylvestris, Phleum pratense, Trollius europaeus, Anthriscus sylvestris, Cirsium heterophyllum, Vicia cracca. Ass. Filipendulo ulmariae–Deschampsietum cespitosae Shushpannikova et Yamalov 2013 of alliance Deschampsion cespitosae Horvatić 1930 (Table 4) was described in wet depressions near the village. Diagnostic taxa are Deschampsia cespitosa and Filipendula ulmaria. Community type Festuca rubra–Ligusticum scothicum of alliance Conioselinion tatarici Golub et al. 2003 (Table 5) occurs on the islands and in floodplain in the Varzuga river mouth. Diagnostic taxa are Ligusticum scothicum, Festuca rubra, Potentilla egedii, Primula finmarchica, Alopecurus arundinaceus, Calamagrostis neglecta, Lathyrus aleuticus, Carex lanceolata, Eleocharis palustris. Floodplain meadows of class Molinio-Arrhena­the­retea are rich of species, with about 140 vascular plants, 20 % of which occur with high constancy (more than 60 % of presence in at least one syntaxa), and 20 % with high cover (more than 5 % at least in one community). The composition of meadows reflects the habitats specific, with short spring flood, regular grazing and mowing, close neighboring of birch and pine forests, tundra zone and White Sea shore. These meadows are worth status of the special protected area «Floodplain meadows in the valley and islands of Varzuga River». If the idea of the National Park «Terskiy Bereg» is revived, the analyzed meadows are to be included in the protected area of natural and cultural heritage, with special regime of mowing and moderate grazing.

Aquatic and semi-aquatic communities of Koryak national district are so far studied very poorly. Only B. Tikhomirov (1935) had cited few data on the aquatic vegetation of Penzhina River basin. This paper presents an analysis of 68 relevés (obtained in 2011–2016) of aquatic, littoral and shore vegetation in the surroundings of Talovskoye lake, the largest lake of the Parapolskiy dol area (Penzhinskiy district, Kamchatka Territory). The plant community classification was elaborated using the Russian school dominant-determinant approach. The vegetation of water area and lake shores is referred to Potamogetonetion, Limoselletion, Phragmitetion vegetation types; that of flood-plain terraces to Festucetion pratensis and Salicetion. 23 formations and 30 associations (including 2 new ones) were characterized. The vegetation cover of Talovskoye lake and its surroundings is low in species number and community diversity. Oligotrophic communities, widely spread around Northern Eurasia, predominate. Oligotrophic species are abundant in the aquatic communities while oligomesotrophic and mesotro­phic ones prevailed in oxbows and flood-plain lakes. The high abundance of Arctophila fulva, Batrachium trichophyllum, Callitriche palustris, Caltha palustris subsp. sibirica, C. natans, Deschampsia komarovii, Eleocharis acicularis, Glyceria lithuanica, Hippuris vulgaris, Limosella aquatica, Myriophyllum verticillatum, Persicaria lapathifolia, Potamogeton gramineus, Ranunculus gmelinii, R. reptans, Sparganium angustifolium, S. emersum, S. hyperboreum, S. natans, Subularia aquatica is common in seasonally drained sites of the lake bottom. The shores of small-size lakes (250–300 m in diameter) are usually low and swampy. Hydrophyte vegetation is represented by pondweed (Potamogeton gramineus, P. perfoliatus) and bur-reed communities (Sparganium emersum, S. angustifolium, S. hyperboreum). The onshore helophyte communities dominated by Carex rhynchophysa, C. rostrata, Comarum palustre, Eriophorum polystachyon, Hippuris vulgaris, and Menyanthes trifoliata form narrow strips. Underdeveloped aquatic and semi-aquatic littoral vegetation is character for medium-size lakes (300–700 м in diameter). The helophyte border (up to 3 m wide) is well developed along the whole lake shore line. Sometimes the swampy shores and quagmires with the predominance of Menyanthes trifoliata are met; occasionally the stretches of boggy shores with the predominance of cotton grass (Eriophorum)–Sphagnum-rich communities occur. The lakes of medium-size are filled by well-developed aquatic and littoral ve­getation. About 30 % of shoreline is occupied by wide (10 m wide and more) helophyte stripe formed by the thickets of Equisetum fluviatile, Arctophila fulva, Cicuta virosa, Comarum palustre, Carex rhynchophysa, C. rostrata. The hydrophyte communities­ are made by pondweeds (Potamogeton gramineus, P. perfoliatus), Myriophyllum verticillatum, sometimes by Utricularia intermedia, U. macrorhiza that formed thickets in the water profile. On the lake shores, lowland grass meadows with the predominance of Arctophila fulva, Glyceria lithuanica, Deschampsia komarovii occurred as well as shrubby willow thickets (Salix pulchra). Grass meadows (Calamagrostis purpurea subsp. langsdorffii) and large-sedge communities are common on the lake shores. The large-size lakes (more than 700 m in diameter) have the vast areas of shallow water. These are the ­areas of littoral helophyte communities. Monodominant thickets of Arctophila fulva and Equisetum fluviatile occupy the shallow waters rich by organic matter. On seasonally drained clay and sandy loam bottoms, Senecio palustris predominates. Along the shores wide strips of sedge hummocks (Carex appendiculata) stretched alternating with the patches of swampy sedge communities (C. cryptocarpa, C. rostrata) with admixture of Cicuta virosa. Further from the lake shores, the flooded grass meadows and shrub willow thickets are common. The long-drained lake basins are occupied by Arctophila fulva, sedge communities and hygrophilous herbs. Floodplain grass-rich meadows (Calamagrostis purpurea subsp. langsdorffii, Glyceria lithuanica, Deschampsia komarovii) and hummocky sedge communities (Carex appendiculata) covered the low shores of Talovskoye lake. The vast shallow water zone adjoined to the shores is occupied by the monodominant helophytic communities (Arctophila fulva, Caltha natans, Hippuris vulgaris, Equisetum fluviatile) and hydrophytic communities dominated by Sparganium emersum, S. angustifolium, S. hyperboreum, S. natans, Potamogeton gramineus, P. perfoliatus, Myriophyllum verticillatum and others. The Lake is surrounded by shrubby willow thickets (Salix pulchra) with the grass layer formed by Calamagrostis purpurea subsp. langsdorffii, Rubus arcticus, Carex cryptocarpa. The survey of the vegetation units of Talovskoye lake and its surroundings had revealed 4 vegetation types, 23 formations and 30 associations, according to dominant-determinant approach. There are communities of 19 formations and 21 associations on the waters of the Lake and on its drained bottom; of 2 formations and 5 associations in the floodplain ponds and oxbows; of 2 formations and 4 associations on the low lakeside terraces. Hygromesophyte grass meadows (Calamagrostis purpurea subsp. langsdorffii) and hygrophyte sedge and grass stands (Glyceria lithuanica, Carex appendiculata) formed the plant cover of low terraces. There are also communities of willow shrubs (Salix pulchra) which are not discussed in the present paper. The main characteristic features of the syntaxonomic composition of the aquatic, littoral and shore vegetation of Talovskoye lake are the absence of numerous syntaxa that are common for the Kamchatka Peninsula: nymphaea (Nupharetosa) and free-floating aquatic vegetation (Lemnetosa minoris); communities of underwater rooting spore-bearing plants (Isoёtоsa). The low community diversity of submerged rooted plants (Potamogetonetosum) is noticed. So, in Talovskoye lake several pondweed formations (Potamogetoneta pectinati, P. pusilli, P. praelongi, P. friesii) widely spread in Eurasia and Kamchatka Peninsula, were not found. Two new syntaxa — Deschampsietum komarovii ranunculosum gmelinii and Glycerietum lithuanicae deschampsiosum komarovii — are suggested for the damp meadows with the predominance of Deschampsia komarovii and Glyceria lithuanica. The communities formed by D. komarovii are endemic for the north of the Far East. The lack of the published relevѐs of these communities confirmed their poor knowledge. Glyceria lithuanica has Eurasiatic areal but it is rarely recorded as edificator. In some regions of the European Russia, this species, considered as the very rare, is included into regional Red Data Books (Skvortsov et al., 2000). The main part of formations and associations found for Talovskoye lake and its surroundings had large distribution areas due to the wide geographical distribution of the dominants and the similarity of the ecological conditions of aquatic and littoral habitats of different regions of Northern Eurasia. The formation Deschampsieta komarovii is considered to be endemic for the North of the Far East. Unusually dry season of 2016 allowed describing the communities of herbaceous annuals (ephemeras). They were assigned to the special vegetation type Limoselletion. A new class of formations Callitrichetosa palustris, united the aquatic communities with the predominance of rooting perennial amphibian plants adapted to periodic drying, is distinguished. Together with the communities of annual hygrophytes, it corresponds to the alliance Eleocharition acicularis Pietsch ex Dierßen 1975 (Dierßen, 1996; Šumberová, 2011; Šumberová et al., 2011a, b). The resemblance of a large part of syntaxa of aquatic and semi-aquatic communities in two classifications may be explained by their mono- or oligodominance and low species diversity.

The present study continues a series of publications by the authors on the diversity of the herb vegetation in the floodplains of the Vychegda and Pechora rivers and their tributaries (Komi Republic). The floristic classification of the orders Molinietalia Koch 1926 and Arrhenatheretalia R. Tx. 1931 was published earlier (Shushpannikova, Yamalov, 2013, 2014). The results of classification of communities belonging to the class Phragmito–Magno-Caricetea Klika in Klika et Novák 1941 are discussed in this paper in accordance with principles of the Braun-Blanquet approach (Braun-Blanquet, 1964; Mirkin, Naumova, 1998). Analysis was based on 268 relevés made in 1981–2016. The assessment of environmental parameters was performed by ecological methods by L. G. Ramensky (Ramensky et al., 1956). Syntaxonomic diversity of the vegetation of the class Phragmito–Magno-Caricetea in the floodplain of rivers Vychegda and Pechora is presented by 3 orders (Phragmitetalia W. Koch 1926, Oenanthetalia aquaticae Hejny in Kopecky et Hejny 1965 and Magno-Caricetalia Pignatti 1953), 4 alliances (Phragmition communis W. Koch 1926, Nardosmion laevigatae Klotz et Köck 1986, Equisetion arvensis Mirkin. et Naumova in Kononov et al. 1989 emend. Taran 1995 and Magnocaricion elatae Koch 1926) and 13 associations. The communities of the class Phragmito–Magno-Caricetea, as well as the order Molinietalia of Molinio–Arrhenatheretea, are located at all levels of the floodplains and are characterized by a variety of humidification conditions. However, the communities of the class Phragmito–Magno-Caricetea are characterized by higher humidification indices (72.2–86.3) compared to meadow vegetation the order Molinietalia of the class Molinio-Arrhenatheretea of (68.8–74.4). A lot of associations, heterogeneous in their floristic composition, can be divided into 9 subassociations and 10 variants. New 4 subassociations (caricetosum vesicariae, equisetosum fluviatilis, persicaretosum amphibiae and lysimachetosum vulgaris), are included into ass. Caricetum gracilis Savich 1926. The peculiarities of the floristic composition of the above mentioned associations, as well as their distribution and ecology are discussed. The distinguished associations are well differentiated by their elevation position on the floodplains. The communities of the ass. Caricetum gracilis are located at all levels of the floodplainons; these of Agrostio stoloniferae–Equisetetum arvensis — on the highest ones; Equisetetum fluviatilis — on the lowest part of the floodplains in the riparian zone. The described communities are located on the soils with various ecological indi­cators. The distinguished associations are differentiated by the levels of humidification (65.9–89.9), mean figures — 70.3–86.3. The communities of the ass. Agrostio stoloniferae–Equisetetum arvensis occupy the driest sites (65.9–72.9); these of associations ­Equisetetum fluviatilis and Nardosmietum laevigatae — the wettest ones (80.7–87.8). The ass. Caricetum aquatilis has a wide range of humidification (72.7–89.9). The variability of humidification varies from alternating to high values (6.4–12.0). The ­greatest differences in humidification are experienced by the communities of the ass. Caricetum gracilis (5.5–12.0). Тhe communities of the ass. Agrostio stoloniferae–Equisetetum arvensis occupy the richest (10.5–15.0) and alluvial soils (4.0–5.0). They are located on the low level in the riverine and middle zone of the floodplain and are formed by annual flooding on alluvial deposits. The distinguished associations are differentiated by pH (3.0–8.0), mean figures — 4.5–7.0. The communities of the associations Caricetum juncellae, Caricetum gracilis and Caricetum acutae–rostratae are located on the most acidic soil; these of the ass. Equisetetum fluviatilis — on the neutral ones. The associations are distributed by the scale of pasture digression in range 2.5–4.5, mean figures — 3.0–3.9. The communities are used for hay-making. The question of the boundary between the meadow vegetation, lowland swamp and semi-aquatic vegetation remains unsolved. The communities of the class Phragmito–Magno-Caricetea described in this paper belongs to meadows. Ass. Nardosmietum laevigatae (previously referred to the class Galio-Urticetea Pass. 1967) is included into the order Phragmitetalia W. Koch 1926. The communities of the ass. Agrostio stoloniferae–Equisetetum arvensis have a mesophilic species composition and low moisture values, so they represent a transition between the class Molinio-Arrhenatheretea order Molinietalia and class Phragmito–Magno-Caricetea. A comparison of species composition of the syntaxa in Komi Republic and that in other regions of the Eastern Europe and the Asian part of Russia showed that the semiaquatic communities of the Komi Republic have low species diversity. It is less than 16 species on sample plot. The richest are communities of the associations Caricetum gracilis and Carici acutae–Phalaroidetum arundinaceae. 101 vascular plant species are recorded in 268 geobotanical relevés of the class Phragmito–Magno-Caricetea. The aboveground phytomass varies from 30–80 g/m2 (Agrostio stoloniferae–Equisetetum arvensis) to 420 г/м2 (Phalaroidetum arundinaceae).

The processes of depletion of zonal vegetation are closely related to the settlement of invasive species. Within the forest ecosystems of the urban district of Voronezh, 31 invasive species from 30 genera and 19 families were recorded. The method of ecological scales revealed the ecological-coenotic aspects of phytoinvasions. The sample involved geobotanical descriptions (grouped by formational feature) of native phytocenoses without an alien component in the flora and phytocenoses replacing them with the active participation of invasive species within the same research object. Infestations of these species are accompanied by the development of allogeneic successions, which are characterized by a decrease in the species diversity of communities and the role of native taxa in them. The processes of infestations are typical for the region and are observed in communities of floodplain forests and meadows, native and derived forests and sub-forests, broad-leaved and mixed forests, slope meadow and steppes. Plant invasions in the coniferous and deciduous forests of the district are characterized by the expansion of 3 species of woody (Acer negundo, Fraxinus pennsylvanica, Robinia pseudoacacia), 5 species of shrub (Sambucus racemosa, Caragana arborescens Lam., Viburnum lantana, Amelanchier spicata, Parthenocissus quinquefolia) and 4 species of herbaceous plants (Bidens frondosa, Impatiens parviflora, Galinsoga parviflora, Solidago canadensis). Phytoindication of pine forests shows the transformation of all 10 environmental indicators for communities with invasive species. For broad-leaved forests, the introduction of biomorphologically close taxa to native species does not lead to a sharp transformation of the ecological parameters of forest biotopes. The introduction of alien species into alder forests leads to a change in the ecological parameters of their biotopes towards mesophilization. This speeds up the process of the emergence of new alien species from the number of mesophytic taxa and an increase in the role of already settled ones. From 2007 to 2017, the invasive flora of the alder forests of the Voronezh increased from one species to four. According to the degree of invasiveness, the ecosystems of the southern upland, southwest oak forest, northern upland oak forests and pine forests have average values of 6.4 %, 6.1 %, 5.1 %, 5.7 %, respectively. Alder forests are minimally invasive, the share of invasive species is 1.3 %, which does not exceed 5 % of the threshold. Minor changes cover indicators: climate thermal mode (TM), continental climate (KN), climate aridity / humidity (OM), cryoclimatic (CR), soil trophicity (TR), soil acidity (RC), moisture variability (FH). Communities with a high level of participation of invasive species are actively developing in ecotonic conditions: forest edges and alder areas of terraces. As a result of the settlement of alien species in the Alder forests, a decrease in the price activity of the following native species is observed: Impatiens noli-tangere, Humulus lupulus, Solanum dulcamara, Thelypteris palustris, Paris quadrifolia, Maianthemum bifolium. To warn of the possible expansion of Acer negundo, Parthenocissus quinquefolia and Galinsoga parviflora, a high water cut regime for alder forests is required. Under the conditions of global and climatic changes, this is a rather complicated task, requiring constant monitoring of the abiotic and biotic components of the forest, as well as the regulation of nature management regimes in the floodplains of small rivers. The implementation of ecological and cenotic strategies for invasive species in forest communities is accompanied by a restructuring of the ecology of biotopes, which is expressed in the transformation of the ecological parameters of pine forests, mesophilization of alder biotopes, increasing the moisture content and richness of oak forests, the emergence of new alien species and reducing the cenotic activity of some native taxa. The most significant changes are subject to parameters: soil moisture (HD), soil nitrogen richness (NT), illumination/shading (LC).

General characteristic of approaches of Russian and Western European phytosociologists to the typology of territorial units of vegetation is presented in the paper. Two-dimensional classification of vegetation proposed by V. Sochava (1968) is the basis of Russian approaches, in which 2 classification categories are identified: phytocenomers and phytocenochores. Homogeneous territorial vegetation units are represented by phytocenoses of a certain syntaxa (phytocenomer), then 3 main types are distinguished within heterogeneous units: complexes, ecological series, and ecological-genetic series (Rachkovskaya, 1963; Guricheva, 1965; Isachenko, 1967; Gribova, Isachenko, 1972). In Western European phytocoenology, the approach to the analysis of territorial vegetation units was introduced by R. Tüxen, who in the 1970s created the foundations of the research topic called symphytosociology (Tüxen, 1973, 1978). He developed the approach to include different levels of syntaxa in the classification of territorial units of vegetation. In 1973, R. Tüxen proposed a methodology for the study of vegetation complexes and the method for converting syntaxa into sigma-syntaxa. In 1981, J.-M. Géhu and S. Rivas-Martínez suggested sigmetum as the main unit of symphytosociology. In 1982, S. Rivas-Martínez proposed the tesela as an elementary territorial unit of chorology and phytogeography. Tesela corresponds to the environmentally homogeneous area and includes communities of one sigmeta. The next level of plant cover organization is the catena — territorial vegetation unit determined by geomorphological features of the area. A catena includes several teselas spatially arranged in a mosaic or arranged in belts following to one or more environmental gradients. Geosigmetum or geoseries is the main typological unit of vegetation of the catena. We took into account the disadvantages of these approaches in the development of a proprietary typological scheme. The lack of a rigorous methodology for allocation and identifying territorial units of vegetation, absence of generally recognized nomenclature, and only intuitive level of allocation of the units themselves are disadvantages of the Russian school. The symphytosociological approach is formal in the scientific terms since it does not take into account the important structural features of the territorial units of vegetation. This approach simplifies their characterization to a list of syntaxa and their combinations and is limited to only two levels of the hierarchy (sigmetum and geosigmetum). The approaches to the typology of territorial units of vegetation, currently used in symphytosociology, are a copy of phytosociological ones. Despite this, the logic of map legend formation differs from the principles of vegetation classification. We propose the types of structures (ecological-genetic series, ecological series, complexes) of the existing communities’ combinations to take as a basis of the typological scheme. They reflect the quintessence of the “ecological basis” of phytocenochore habitats, namely the distribution features, intensity, direction, and the result of the interaction between environmental factors. The unification of territorial units of vegetation is carried out based on real and regularly repeated combinations of higher rank (from micro- to meso- level and so on). This allows us to reflect levels of a hierarchical organization of vegetation in the typology and nomenclature. The vegetation of the Barents sea coastal marches was chosen as a model object due to the well-studied syntaxonomic composition and pronounced spatial patterning. This patterning appears mainly due to the discrete gradation of the prevailing environmental factors: the degree of salinity and moisture of the substrate. Within the framework of the typological scheme, the most general categories of territorial units are identified. They correspond to the basic levels of the hierarchical organization of vegetation cover — division, class, and type, which are highly likely to be common to any mapped territory, regardless of its zonal disposition. For a more complete display of the structure and complexity of the spatial organization of phytocenochores, 3 auxiliary categories were introduced — subclass, group, and subtype. Division — is the highest unit of a typological scheme that combines the territorial units of vegetation of a particular natural area confined to such geomorphologic structures as following: 1) watersheds covering the area between the edge of the slopes of the bed-rock terraces in river valleys; 2) river valleys exposed to the flooding regime, the boundaries of this geomorphologic structures are drawn on the edge of the slope, which separates the valleys from the watershed areas; 3) low marine terraces variably flooded by tidal waters, this geomorphologic structure is limited by the bed-rock terrace slope edge. Class is the subordinated unit within the division. They combine topographically well differed territorial units of vegetation, in which the composition of syntaxa and syntaxon combinations reflect the ecological specificity of simple relief forms of the same origin (i. e. hill, ridge, runoff hollow, lake depression, floodplain, etc.) or their elements (slopes, terraces). Phytocenochores of the class rank are formed by combinations of communities, different in ecology (palsa-bogs, coastal marshes, etc.). This is due to the specific distribution and influence of environmental factors and their combinations within the class. The syntaxonomic composition of communities and their combinations within the class reflects the position of vegetation territorial units in the landscape and their habitats’ ecological distinctiveness. The territorial units of vegetation of the same class within different subzones and geobotanical districts can differ significantly in composition (diagnostic syntaxa and the main elements of their combinations) due to the zonal and regional originality. It is the basis for their allocation to the rank of subclass. Phytocenochores of subclasses are usually not territorially conjugate and belong to different units of geobotanical zoning (subzones, geobotanical districts). The class of territorial units of Barents Sea coastal marshes is divided into salt and brackish marsh subclasses. They belong to different geobotanic districts and are considered as ecological variants of coastal marsh class with a uniqueness of composition of syntaxa and their combinations. Within the class/subclass of vegetation territorial units, phytocenochores of meso- or macro-level are often clearly distinguished, discretely, or continually replacing each other along the gradient of leading environmental factors. They were allocated to the rank of group, each is physiognomically distinct and represented by a continuum or relatively homogeneous mosaic of syntaxa and their combinations. The composition of diagnostic syntaxa and their combinations, reflecting the ecological peculiarity of the habitats of this typological unit and the class (subclass) as a whole, is preserved within the group. Groups are territorially conjugate and represent elements within a uniform ecological or ecological-dynamic series of communities and their combinations. The definition of groups, as well as subclasses, can be problematic because of the complexity of the geomorphological features. This is the reason why this typological unit has an auxiliary character. Type — the basic elementary unit of the typological scheme, displayed mainly on maps of large and medium scales. To distinguish the type two main criteria are being applied as follows: 1) the type of spatial structure, and 2) syntaxonomic composition of the elements of the vegetation territorial unit. As a type the following phytocenochores can be recognized: 1) phytocenoses; 2) simple combinations of the first supraphytocenotic level (ecological-genetic series, ecological series, complexes); 3) complex combinations that include a combination of phytocenochores of the first 2 types. The types represented by heterogeneous territorial units of vegetation include complete combinations of all possible elements of phytocenochores (series, ecological series, etc.) that can occur in the conditions of type habitats. Usually, within the phytocenochores, combinations of communities are represented by the selective set of syntaxa represented in the complete combinations. For a comprehensive inventory of the regional territorial units, diversity, and its reflection on the maps, auxiliary typological unit of subtype rank is introduced, which manifests the internal variability of a certain type and reflects the completeness of the type representation in a particular territory. For the names of typological units of different ranks, it is proposed to use the names of diagnostic syntaxa of association and lower rank, since they most reflect the local and regional originality of the mapping area. The Brown-Blanquet approach to the classification of vegetation, as the methodically most developed among others nowadays, is the basis for the nomenclature of typological units. For the name of typological units, we propose to use the ending “-chorietum”, derived from phytocenochora (coenochora). It reflects the chorological aspect of the unit and intended to be used in the nomenclature for all of the territorial vegetation units categories — of any rank of complexity and to rankless territorial units. The term -chorietum is added to the name of the diagnostic syntaxon. For homogeneous territorial units, we propose to use syntaxon name, since any phytocoenosis is an elementary territorial unit of vegetation of the rank of association and below. For simple combinations (ecological-genetic series, ecological series, complexes), regardless of the number of their forming syntaxa, the names of two syntaxa are used. The ending -chorietum is added to the genus name of the taxon of diagnostic syntaxon. This reflects the first supraphytocoenotic level of the structural organization of the territorial unit of vegetation. If the diagnostic syntaxon has the rank of subassociation or variant, then name of the typological unit uses name of the association with the ending -chorietum, followed by the full name of the subassociation or variant. If the type of territorial units is represented by an incomplete series of syntaxa and is assigned to a subtype, then after the diagnostic syntaxon the ending -subchorietum is used. If the type is represented by a complex combination of phytocoenoses and their combinations, the name of the diagnostic syntaxon with the ending -synchorietum is used. When forming the names of typological units of class and lower rank, add the ending corresponding to their rank to the basis of the genus name of the taxon of the diagnostic association, that is, instead of the -etum ending, we use the ending corresponding to the rank of the territorial unit. If the basis of the genus name ends in a consonant, then we use the connecting vowel (“i” or “o” following to Appendix I of the ICPN). If the name of the rank of the phytocenochore consists of the names of two syntaxa, then the first diagnostic syntaxon is unchanged, and the ending corresponding to the rank is added to the last syntaxon. Examples: for class —-chorietea (Luzulo confusae–Salicichorietea nummulariae), subclass — -subchorietea(Puccinellisubchorietea phryganodis), group — -chorieteum(Caricichorieteum glareosae), type — -chorietum (Callitricho–Ranunculetum trichophylli—Carici rariflorae–Salicichorietum glaucae) and -synchorietum (Caricetum subspathaceae arctanthemetosum hulteni—Potamogetonosynchorietum filiformis), subtype — -subchorietum (Parnassio palustris–Salicetum reptantis—Scirpo–Hippuridosubchorietum tetraphyllae). To name division, which represents the highest rank, the term choriophyta is proposed. The term has been added to the Latin names of the divisions of the tundra zone, for example, watersheds — Tundra divortium choriophyta, river valleys — Tundra vallis choriophyta, low sea terraces — Tundra maritimes choriophyta. To describe and display the spatial structure of phytocenochore types represented by simple and complex combinations, it is proposed to use the set of symbols reflecting the structural features. Using the example of coastal marshes of the Haypudyrskaya Bay of the Barents Sea (Puccinellichorietea phryganodis), a typological scheme of territorial vegetation units was developed. The subclass of salt marshes (Puccinellisubchorietea phryganodis) was taken for a case study. Within the subclass 4 groups of 27 categories were selected to create the geobotanical map (1 : 25 000). Those categories are of the rank of types and subtypes of different complexity levels and 13 homogeneous and 14 heterogeneous are among them. In addition to them, 5 types of phytocenochores that intrude marshes from adjacent divisions have been identified. The application of the typological scheme allows taking into account not only the syntaxonomic composition and predominant combinations but also their patterning and complexity. This will largely reflect the originality of the vegetation of the given area, as well as habitas specificity, geomorphological and ecological features of the territory.