Communities of the class Festuco-Puccinellietea Soó ex Vicherek 1973 on the territory of Eurasia

A survey and revision of the highest syntaxa of the class Festuco-Puccinellietea with the exception of plant communities attributed to the class Scorzonero—Juncetea gerardii are submitted. Communities of the Festuco-Puccinellietea are inland intrazonal stands of Eura­sia on solonetz soils, most common in flat lowlands as well on the rivers and lakes terraces that are briefly flooded in spring-time, and dry for the most part of the growing season. The diagnostic species combi­nation of the class is heterogeneous. It includes Arte­misia dwarf semi-shrubs of the Seriphidium section that are widely spread in the Iran-Turan subregion of the Sahara-Gobi area. These are also Limonium species that are mostly diverse in the Mediterranean region where from these taxa could move into inland areas with solonetz soils. The Festuca taxa of the section Festuca together with Poa bulbosa have probably moved on solonetz soils from adjoining steppes. The halophytic Puccinellia taxa of Xeratropis and Puc­cinellia sections could penetrate into Festuco-Puccinellietea communities from the banks saline pools. The floristic composition of the class in question gives the bright example of the net-shaped evolution of plant communities according to Whittaker (1980). The distri­bution area of Festuco-Puccinellietea communities lies within the Black Sea-Kazakhstan subregion of the Eurasian Steppe region according to the subdivision of the Ancient Mediterranean by Lavrenko (1962, 1970а). There are no communities that could be placed in Festuco-Puccinellietea in Central Asia, at least the authors were not lucky to find any signs of these in references. The closest to this class are the communities of Achnatheretea splendentis, however their floristic composition and ecology are significantly different. Within the whole area of their distribution the Festuco-Puccinellietea communities are neighboring with those of Scorzonero—Juncetea gerardii occupying shallow depressions, while in the steppe zone they occur close to zonal phytocenoses on placor belonging to Festuco-Brometea. There is no idea what kinds of semidesert zonal vegetation are contiguous with Festuco-Puccinellietea communities because it is still been poorly studied from the point of view of the Braun-Blanquet approach. Syntaxa that belong to Festuco-Puccinellietea are so far poorly studied on the vast area of Ukraine, as well as Krasnodar and Stavropol regions, the Don River basin, the territory between the Don and Volga rivers of Russia, and Northern Kazakhstan.