Forest Steppe-Like Vegetation Near Cherskiy (West Beringia) During the Early Pleistocene Olyorian Period Reconstructed Using Plant Macrofossils

The lower Kolyma region is known for rich Early Olyorian large mammal assemblages including plesiomorphic musk ox, reindeer, horse, broad-fronted moose, steppe mammoth and cave bear. Data on the vegetation in zonal habitats from the Olyorian period are, in contrast, scarce. Earlier palynological results from classical Olyorian sites indicated predominant grassland vegetation with scattered larch occurrences but are, due to limited taxonomical resolution, uncertain. Plant macrofossil data were, so far, only available from azonal, aquatic habitats. Here, we describe Olyorian palaeo-vegetation from an exposure near Cherskiy, Nizhnekolymsky District, Sakha Republic, Russia. The macrofossil-based reconstruction of palaeo-vegetation revealed the existence of an open forest steppe comprising a mosaic of sparse larch groves in a dry grassland composed of tundra steppes, degraded meadow steppes and saline meadows. In the larch groves, light demanding shrubs and dwarf shrubs such as shrub birch (Betula cf. fruticosa, B. nana ssp. exilis), raspberry (Rubus idaeus), cowberry (Vaccinium vitis-idaea), and crowberry (Empetrum nigrum) formed the understory. Ruderal pioneer plants point to open ground as result of disturbances, possibly due to the activity of large herbivores. The nitrophytic ruderal species Urtica dioica, in particular, suggests locally increased nutrient supply from animal excretions. Also, the abundant remains of Chenopodium cf. prostratum might be explained by disturbances and nutrient enrichment, but Chenopodium is also characteristic of salt accumulation in the soil owing to high evaporation under arid conditions, which are also indicated by alkali grass (Puccinellia sp.). The presence of trees and shrubs indicates interglacial-like temperature conditions but the dominance of dry grassland species and the occurrence of facultatively halophytic plants (Chenopodium prostratum, Puccinellia sp.) suggests aridity, which is more typical of cold stages. During the early Pleistocene, i.e., prior to the Early-Middle Pleistocene transition (EMPT) culminating around 900 ka ago, the duration of climate cycles was shorter and the amplitude of climate fluctuations was smaller. Ice-rich permafrost formed only after the EMPT during increasingly extreme cold stages, and, during warm stages, its thawing resulted in paludification of the active layer. Prior to the EMPT, the climate in West Beringia was constantly relatively dry, more or less moderate and more stable than thereafter. In contrast to modern tundra and northern taiga in the study region, dry habitats apparently prevailed during the time of deposition of the plant macro-remains.

Pollinator guilds respond contrastingly at different scales to landscape parameters of land-use intensity

Land-use intensification is the main factor for the catastrophic decline of insect pollinators. However, land-use intensification includes multiple processes that act across various scales and should affect pollinator guilds differently depending on their ecology. We aimed to reveal how two main pollinator guilds, wild bees (specialists) and hoverflies (generalists), respond to different land-use intensification measures, i.e. arable field cover (AFC), landscape heterogeneity (LH) and functional flower composition of local plant communities as a measure of habitat quality. We sampled wild bees and hoverflies on 22 dry grassland sites within a highly intensified landscape (NE Germany) within three campaigns using pan traps. We estimated AFC and LH on consecutive radii (60-3000m) around the dry grassland sites and estimated the local functional flower composition. Wild bee species richness and abundance was positively affected by LH and negatively by AFC at small scales (140-400m). In contrast, hoverflies were positively affected by AFC and negatively by LH at larger scales (500-3000m), where both landscape parameters were negatively correlated to each other. At small spatial scales, though, LH had a positive effect on hoverflies abundance. Functional flower diversity had no positive effect on pollinators, but conspicuous flowers seem to attract abundance of both guilds. In conclusion, landscape parameters contrarily affect two pollinator guilds at different scales. The correlation of landscape parameters may influence the observed relationships between landscape parameters and pollinators. Hence, effects of land-use intensification seems to be highly landscape-specific.

Long term changes of the inner-alpine steppe vegetation: the dry grassland communities of the Vinschgau (South Tyrol, Italy) 40–50 years after the first vegetation mapping

Aims: The Vinschgau is the driest inner-alpine valley in the Eastern Alps and harbours a unique steppe vegetation. We studied these dry grassland communities and aimed to answer the following questions: Which plant communities can be found currently? Do the syntaxa described by Braun-Blanquet in the 1960s still prevail in the area? Has there been any change in species composition over the last 40–50 years? Study area: Along an approximately 40 km transect, the south-facing slopes of the Vinschgau valley (South Tyrol, Italy) from Mals to Plaus were investigated. Methods: For the classification, 92 relevés were sampled in 2019 and compared with 76 relevés from the 1960s and ´70s by means of vegetation tables and ordinations (Detrended Correspondence Analysis). Results: Based on our investigation, the majority of dry grassland communities can be classified as Festuco-Caricetum supinae. Three subassociations were defined by the dominant species Stipa capillata, Bothriochloa ischaemum and Stipa pennataagg. The comparison of new and old relevés shows an increase in species from the class Sedo-Scleranthetea (e.g. Trifolium arvense, Erodium cicutarium) and the association Artemisieto-Agropyretum. In addition, ruderal elements (e.g. Erigeron annuus, Convolvulus arvensis) have also migrated into dry grasslands. A shift in the dominance over time can be recognized as well. In particular, Festuca rupicola and to some extent also Stipa capillata, have increased in abundance and frequency. Conclusions: We suggest to include the investigated closed dry grasslands in the alliance Festucion valesiacae. The rank of the character species at association, alliance and order level should be re-analysed. In order to obtain a better syntaxonomic overview of western and eastern alpine dry grassland communities in relation to Eastern European dry grasslands, a comprehensive study is absolutely necessary. Furthermore, long-term vegetation dynamics and vegetation change need to be studied in more detailed future studies. Taxonomic reference: Fischer et al. (2008). Syntaxonomic references: Mucina et al. (2016) for syntaxa from alliance to class level; Braun-Blanquet (1961) for associations. Abbreviations: agg. = aggregate; cf. = confer (means ‘compare’); DCA = Detrended Correspondence Analysis; s. lat. = sensu lato; s. str. = sensu stricto

Xeric grasslands of the inner-alpine dry valleys of Austria – new insights into syntaxonomy, diversity and ecology

Aims: We studied the syntaxonomic position, biodiversity, ecological features, nature conservation value and current status of dry grasslands investigated by Josias Braun-Blanquet more than 60 years ago. Study area: Inner-alpine valleys of Austria. Methods: We sampled 67 plots of 10 m2, following the standardized EDGG methodology. We subjected our plots to an unsupervised classification with the modified TWINSPAN algorithm and interpreted the branches of the dendrogram syntaxonomically. Biodiversity, structural and ecological characteristics of the resulting vegetation units at association and order level were compared by ANOVAs. Results: All the examined grasslands belong to the class Festuco-Brometea. From ten distinguished clusters, we could assign four clusters to validly published associations, while the remaining six clusters were named tentatively. We classified them into three orders: Stipo-Festucetalia pallentis (Armerio elongatae-Potentilletum arenariae, Phleo phleoidis-Pulsatilletum nigricantis, Medicago minima-Melica ciliata community, Koelerio pyramidatae-Teucrietum montani), Festucetalia valesiacae (Sempervivum tectorum-Festuca valesiaca community); Brachypodietalia pinnati (Astragalo onobrychidis-Brometum erecti, Agrostis capillaris-Avenula adsurgens community, Anthericum ramosum-Brachypodium pinnatum community, Ranunculus bulbosus-Festuca rubra community, Carduus defloratus-Brachypodium pinnatum community). Conclusions: The ten distinguished dry grassland communities of the Austrian inner-alpine valleys differ in their ecological affinities as well as their vascular plant, bryophyte and lichen diversity. We point out their high nature conservation importance, as each of them presents a unique habitat of high value. Taxonomic reference: Names of vascular plants, bryophytes and lichens follow Fischer et al. (2008), Frahm and Frey (2004) and Nimis et al. (2018), respectively. Syntaxonomic reference: Names of orders and classes follow Mucina et al. (2016), references for associations and alliances are given in the text. Abbreviations: ANOVA = analysis of variance; DCA: detrended correspondence analyses; EDGG: Eurasian Dry Grassland Group; EIV: ecological indicator value; FL: Fließ; GR: Griffen; GU: Gulsen; KA: Kaunerberg; LA: Laudegg castle in Ladis; MA: Marin; NM: Neumarkt in der Steiermark; OM: Obermauern; PÖ: Pöls; PU: Puxer Loch; TWINSPAN = Two-way indicator species analysis; ZS: Zinizachspitze.

Phytosociology of Atractylis cancellata and Micromeria microphylla communities in southern Italy with insights on the xerothermic steno-Mediterranean grasslands high-rank syntaxa

In the present paper a phytosociological study on the dry grassland communities identified in the western sector of the Murgia Plateau (Murgia delle Gravine) and in the Lucanian badlands territory is presented. Forty vegetation releves were carried out using the Braun-Blanquet phytosociological approach. Two new associations characterized by a therophytic dominance, namely Lysimachio foeminae-Atractylidetum cancellatae and Campanulo erini-Micromerietum microphyllae, are described and discussed from a syntaxonomic and biogeographic viewpoint. In addition, new phytosociological data concerning the Petrosedum ochroleucum communities developed on limestone outcrops, the perennial Hyparrhenia hirta steppe-like grasslands of the low-altitude areas of the Murgia hills and the small-size Brachypodium distachyum therophytic communities are presented.

Impacts of soil disturbance on plant diversity in a dry grassland

Dry grasslands are among the most species rich habitats in Europe, but they are also among the most threatened. Threats include too high and too low levels of disturbance. The aim of this study is to examine the effect of soil disturbance intensity on species composition and diversity in a dry grassland in Mols Bjerge National Park in Denmark. We recorded vascular plant species inside and just outside patches of bare sand, and in the transition zone between these. We found that the number of species was highest in the dense vegetation, intermediate at the transition and lowest in bare sand areas. However, an analysis of plant traits showed that the number of small annual species was highest in the transition zone. High abundance of small annual species may therefore indicate intermediate disturbance regimes. Based on a literature study we demonstrate that many threatened species are adapted to such habitats. This suggests that dry grasslands should be managed to maintain areas with intermediate disturbances intensities to maintain optimal conditions for many threatened species. To our knowledge, this is the first time it has been documented that small annual species can indicate intermediate disturbance regimes in dry grasslands.

Conservation, restoration and biodiversity of Palaearctic grasslands – Editorial to the 6th EDGG special issue in Hacquetia

This special issue is a collection of articles about the conservation, restoration and biodiversity of Palaearctic grasslands and was initiated by the Eurasian Dry Grassland Group at the 15th Eurasian Dry Grassland Conference (EDGC), held at Graz, Austria in 2019. The papers in this special issue cover a range of grassland habitats from montane dry grasslands to lowland sandy grasslands, feathergrass steppes and meadow steppes, and focus on the biodiversity values, conservation issues and restoration prospects of Palaearctic grasslands. We hope that the articles in this special issue will contribute to a better understanding of the ecology of grasslands and support their more effective conservation.