Pannonian and Pontic sandy steppe

Sandy steppe grasslands of the Pannonian and Pontic regions, dominated by drought-tolerant, tussock-forming perennial grasses such as Festuca vaginata, Koeleria glauca and Stipa borysthenica, in eastern Europe also by Festuca beckeri. Besides these grasses, perennial herbs are common in these grasslands, many of them with a deep root system developed as an adaptation to periodical drought events occurring on sandy substrates. Short-lived vernal therophytes, bryophytes and lichens are also frequent. Vegetation is sparse, with a maximum cover of 75%. These grasslands of the order Festuco-Sedetalia acris grow on poorer developed soils than the oceanic and sub-oceanic grasslands of habitat E1.9a. This type is also more continentally distributed (drier climate) and associated with higher soil pH often well above 7, because under continental conditions the soils are much less leached than in more Atlantic climate. In most cases they also have a higher species richness. Frequent occurring continental species are Alyssum tortuosum, Astragalus arenarius, Dianthus arenarius, Dianthus serotinus, Erysimum canum, Euphorbia seguieriana, Gypsophila fastigiata, Helichrysum arenarium, Jurinea cyanoides and Secale sylvestre.

Sandy steppes occur on sandy plains and dunes with variable content of exchangeable cations, both of acidic and basic reaction. On acidic sand, transitions to sub-oceanic sandy grasslands (E1.9b) occur, especially in the western parts of this habitat’s range. Soils are poor in humus, belonging to the Arenosol type. Pannonian and Pontic sandy steppe occurs in lowlands with a pronounced continental climate characterized by warm and dry summer and cold winter, often with very shallow snow cover combined with long periods of frost. The surface layer of sand can warm up quickly during sunny days in summer, while the sandy substrate has a low water-holding capacity resulting in drought stress. Extreme drought events occurring in return intervals of several years can result in changes in species composition and relative cover of dominant species.

There are two main areas of distribution of these continental sandy steppes in Europe. One is the Pontic region including the steppe and forest-steppe zone of Ukraine and southern Russia (alliance Festucion beckeri), extending to the Danube valley in Romania and Bulgaria. The other is the Pannonian region including the Great Hungarian Plain (Alföld) and some adjacent lowland and hilly regions. Here the highest concentration of these grasslands is in central Hungary on the plains between the Danube and Tisza rivers (alliance Festucion vaginatae). Apart from these vicarious alliances dominated by perennial tussock grasses, there are two therophyte-dominated alliances of initial disturbed sites, namely the Sileno conicae-Cerastion semidecandri in the range of the Koelerion glaucae and the Bassio laniflorae-Bromion tectorum in the range of the Festucion vaginatae.

Stands of the alliance Koelerion glaucae can be found also on base rich sand in some areas in Poland, eastern Germany and the middle Rhine valley in western Germany, as well as in the Southern Baltic region (Öland, Finish south coast), but there is some discussion whether such stands should be included under E1.1a or E1.9a. In the Red List typology they have been included in habitat E1.9a, as it was indicated by most national experts from these region that it was not possible to distinguish these vegetation types as different habitats. The habitat type is absent from western Europe, high mountains and more northern regions.

Sandy steppes were used for extensive grazing by domestic livestock, especially sheep. This land-use resulted in extension of their area at the expense of forest, however, after cessation of traditional management many former sand-steppe areas are becoming overgrown by encroaching shrubs and trees such as Pinus sylvestris and Robinia pseudoacacia.

Indicators of good quality:

In Europe sandy steppes contain several species of continental distribution that occur at the western limit of their distribution range. Most valuable are extensive stands of sand steppe on inland dunes or plains with open vegetation without alien or nutrient-demanding species. Sand steppe can develop on abandoned fields adjacent to preserved remnants of natural vegetation, however, alien species may be common in these secondary grasslands. The main threats to this habitat are overgrowing by trees and shrubs after cessation of grazing, spread of alien species such as Robinia pseudoacacia or Asclepias syriaca, and increasing dominance of nutrient-demanding species due to atmospheric deposition.

The following characteristics can be considered as indicators of good quality:

·      Occurrence of rare species, especially those of continental distribution.

·      Absence of nutrient-demanding and mesophilous species.

·      Open character of vegetation.

·      Absence of alien species.

·      Absence of trees and shrubs.

·      Large spatial extent of grassland stands.

·      Continuation of traditional low-intensity grazing management.

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats