Utility of surface pollen assemblages to delimit Eastern Eurasian steppe types

PLoS One. 2015 Mar 12;10(3):e0119412. doi: 10.1371/journal.pone.0119412. eCollection 2015.

Abstract

Modern pollen records have been used to successfully distinguish between specific prairie types in North America. Whether the pollen records can be used to detect the occurrence of Eurasian steppe, or even to further delimit various steppe types was until now unclear. Here we characterized modern pollen assemblages of meadow steppe, typical steppe and desert steppe from eastern Eurasia along an ecological humidity gradient. The multivariate ordination of the pollen data indicated that Eurasian steppe types could be clearly differentiated. The different steppe types could be distinguished primarily by xerophilous elements in the pollen assemblages. Redundancy analysis indicated that the relative abundances of Ephedra, Tamarix, Nitraria and Zygophyllaceae were positively correlated with aridity. The relative abundances of Ephedra increased from meadow steppe to typical steppe and desert steppe. Tamarix and Zygophyllaceae were found in both typical steppe and desert steppe, but not in meadow steppe. Nitraria was only found in desert steppe. The relative abundances of xerophilous elements were greater in desert steppe than in typical steppe. These findings indicate that Eurasian steppe types can be differentiated based on recent pollen rain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • China
  • Ecosystem*
  • Grassland*
  • Humidity
  • Mongolia
  • Pollen*
  • Temperature

Grants and funding

This research was supported by the China National Key Basic Research Program (2014CB954201), the National Natural Science Foundation of China (No. 30990241), and the State Key Laboratory of Systematic and Evolutionary Botany (No. LSEB2012-09). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.