Biodiversity of Palaearctic grasslands: a synthesis

By Jürgen Dengler, M. Janišová, P. Török, Camilla Wellstein. 2014

588 citations recorded by the source corpus.

Abstract This article introduces a Special Issue on biodiversity of Palaearctic grasslands and provides a synthesis of the current knowledge on this topic. Four major categories of grasslands can be distinguished in the Palaearctic biogeographic realm: (a) zonal steppes (in areas too dry for forests), (b) arctic-alpine grasslands (in areas too cold for forests), (c) azonal and extrazonal grasslands (where hydrology, soil conditions, relief or natural disturbances within the forest biomes prevent tree growth locally) and (d) secondary grasslands (which replace natural forests in consequence of human land use). We summarize the present knowledge about species richness patterns (mainly of vascular plants) along abiotic and land use gradients. Further, we highlight the usefulness of diversity measures not based on species richness, namely functional diversity, phylogenetic diversity and within-species diversity. The strong differences observed for diversity patterns according to analyzed biodiversity parameter, spatial scale or taxonomic group call for comparative studies and caution when generalizing results. A particular challenge are the extreme plot-scale species richness values found in grasslands of a few European regions. We propose a conceptual model that explains the findings by an interplay of various factors acting at different levels: (i) The largest species pool is expected for habitats under conditions that prevailed over the last few million years, with a slight shift towards intermediate positions, i.e. for the Palaearctic in open, semi-dry, base-rich situations. (ii) The landscape-level species pool is increased by continuity of a grassland patch in space and time and heterogeneity of the surrounding landscape. (iii) The coexistence of regionally available species at a plot scale is due to reduced competitive exclusion according to Intermediate Disturbance Hypothesis, mowing once a year without fertilization being particularly effective. Ecosystem functions and services of Palaearctic grasslands are often positively connected to their biodiversity. At the same time, these communities and their biota are nowadays highly endangered. The semi-natural (High Nature Value) grasslands of Europe are mainly threatened by agricultural intensification or abandonment on low-productive sites in remote areas, while the natural steppes of the Palaearctic have largely been destroyed by conversion into arable land. Finally, we present some promising conservation and management approaches and call for a strong and comprehensive Convention on Grassland Conservation.

Subfields: Nature and Landscape Conservation, Plant Science

View Paper: https://www.semanticscholar.org/paper/b706d00b42b27adc0b0131154a440bee6e6f56b0

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Nature and Landscape Conservation

1. P. Török
2. A. Helm
3. T. Aavik
4. B. Dumont
5. A. Farruggia
6. Jürgen Dengler
7. K. Wesche
8. M. Pärtel

In Plant Science

1. P. Török
2. A. Helm
3. Jürgen Dengler

Citations in the corpus

• Livestock Type is More Crucial Than Grazing Intensity: Traditional Cattle and Sheep Grazing in Short‐Grass Steppes (2018, unknown): “In conservation of biodiversity in such agriculture-driven landscapes, mesic and dry grasslands have an outstanding importance (WallisdeVries, et al. 1998, Dengler et al., 2014).”
• A biodiversity-friendly rotational grazing system enhancing flower-visiting insect assemblages while maintaining animal and grassland productivity (2017, background): “Similarly, recent studies carried out in European mountain semi-natural grasslands reported comparable outputs in animal performance between CG and rotational grazing systems (Farruggia et al., 2014; Stejskalová et al., 2013).”
• Ecological theory provides strong support for habitat restoration (2017, background): “Finally, there has been a great deal of both theory and restoration driven research in Palearctic grasslands in the last decades (Kiehl et al., 2010; Török et al., 2011; Dengler et al., 2014; Helm et al., 2015; Valkó et al., 2016).”
• The Palaearctic steppe biome: a new synthesis (2016, background): “Drawing boundaries between steppes and neighbouring habitats relies on arbitrary decisions, and estimates on the extent of the Palaearctic steppe biome diverge substantially, stretching from 8 to over 13 million km(2) (Dengler et al. 2014).”
• Restoration of plant species and genetic diversity depends on landscape‐scale dispersal (2018, background): “Large species pool, along with moderate human disturbance, is also related to high small-scale (site level) plant diversity in European grassland habitats (Dengler et al. 2014).”
• Phylogeographic patterns of steppe species in Eastern Central Europe: a review and the implications for conservation (2016, background): “…could be important, as steppic habitats sustain assemblages very rich in species, among which there are many taxa restricted only to this type of environment or even endemic to some steppic areas on a European or local scale (e.g. Pärtel et al. 2005; Mazur and Kubisz 2013; Dengler et al. 2014).”