Phylogeographic patterns of steppe species in Eastern Central Europe: a review and the implications for conservation

Abstract

The phylogeography of species associated with European steppes and extrazonal xeric grasslands is poorly understood. This paper summarizes the results of recent studies on the phylogeography and conservation genetics of animals (20 taxa of beetles, butterflies, reptiles and rodents) and flowering plants (18 taxa) of such, ''steppic'' habitats in Eastern Central Europe. Most species show a similar phylogeographic pattern: relatively high genetic similarity within regional groups of populations and moderate-to-high genetic distinctiveness of populations from currently isolated regions located in the studied area. This distinctiveness of populations suggests a survival here during glacial maxima, including areas north of the Bohemian Massif-Carpathians arc. Steppic species generally do not follow the paradigmatic patterns known for temperate biota (south-north ''contraction-expansion''), but to some extent are similar to those of arctic-alpine taxa. There are three main groups of taxa within Eastern Central Europe that differ in their contemporary distribution pattern, which may reflect historical origin and expansion routes. Present diversity patterns of the studied steppic species suggest that they share a unique genetic signature and distinct assemblages exist in each of the now isolated areas rich in steppic habitats. At least some of these areas probably act as present ''interglacial refugia'' for steppic species. This study strongly supports the need to protect steppic species throughout their entire ranges in the region, as the continuous destruction of steppic habitats in some areas may lead not only to the disappearance of local populations, but also to the extinction of unique evolutionary units.

On the road: Postglacial history and recent expansion of the annual Atriplex tatarica in Europe

“…However, the distribution of steppe species north of the Alps, the Bohemian Massif and the Carpathians is still a matter of debate. Kajtoch et al () named several steppe species ( Inula ensifolia L., Linum flavum L., L. hirsutum L. and Stipa pulcherrima C. Koch) that showed distinct phylogenetic lineages far north in central and southern Germany (see also Meindl, Brune, Listl, Poschlod, & Reisch, ) and southeast Poland as compared to southern European locations. Hence, these northerly situated areas could have been temporarily covered by steppe vegetation during cold periods of some glacials and extant populations of some steppe species in these areas may be remnants of much larger populations of species that were widely distributed during glaciations.…”

Step(pe) up! Raising the profile of the Palaearctic natural grasslands

“…However, the mechanisms in the two regions seem to be different as in Transylvania mainly ruderal species became more diverse on plots located in larger grassland patches, while in Ukraine these were mainly steppe specialists. Kajtoch et al (2016), reviewed a comprehensive set of studies that analysed genetic diversity patterns of 38 typical steppe taxa, both animals and plants, at the western margin of the continuous steppe biome. While the genetic patterns showed various taxon-specific peculiarities, the authors concluded from the relative genetic distinctness of isolated populations in the Pannonian region and in steppe-like grasslands in the Czech Republic, Poland, or Germany, which are normally considered as semi-natural, that many of these species may well have survived there during glaciations and did not just reach there after humans started to open the landscape.…”

“…In the forest-steppe zone, the mosaic character of the landscape with grasslands interspersed by scattered groups of trees and small woods is usually maintained by the grazing of domestic and wild ungulates and wildfires, which all prevent the establishment of extensive closed forests (Bredenkamp et al 2002). Steppes are diverse in their abiotic conditions as well as their biotic composition, and they sustain a high number of endemic species Kajtoch et al 2016). As typical steppes are characterised by fertile soils (often Chernozems), large areas of steppes have been converted to croplands in Europe and parts of Asia.…”

“…Across the Siberian and Central Asian steppes, the Virgin Lands Campaign of the Soviet Union led to Fig. 1 Simplified map of the Palaearctic steppe biome (with main steppe ecoregions after Wesche et al 2016) with localisation of the studies included in this Special Issue: (1) Kuzemko et al (2016); (2) Polyakova et al (2016); (3) Sutcliffe et al (2016); (4) Dembicz et al (2016); (5) Kajtoch et al (2016); (6) Weking et al (2016); (7) Mathar et al (2016); (8) Lameris et al (2016); (9) Wang and Wesche (2016); (10) Addison and Greiner (2016); (11) Niu et al (2016); (12) Novenko et al (2016); (13) Deák et al (2016); (14) Ambarlı et al (2016); (15) Kamp et al (2016); (16) Brinkert et al (2016); (17) Kämpf et al (2016). Reviews summarising data across countries are indicated by large asterisks (i.e.…”

“…1). Two contributions (Kajtoch et al 2016;Sutcliffe et al 2016) largely refer to semi-natural and extrazonal dry grasslands outside the steppe biome, addressing processes in these steppe-like grasslands that are also relevant for the natural steppes and can partly be connected to past situations when the respective study areas still belonged to the steppe biome.…”