Desert grassland dynamics estimated from carbon isotopes in grass phytoliths and soil organic matter

Mitchel P. McClaran, Marcelle Umlauf

Research output: Contribution to journalArticlepeer-review

47 Scopus citations

Abstract

We document the potential for using carbon isotopes in both soil organic matter (SOM) and grass phytoliths in soil to increase the temporal and taxonomic resolutions of long term vegetation dynamics. Carbon isotope values from both SOM and phytoliths are expected to describe both the age of material through 14C dating, and the photosynthetic pathway of the source plant material through ratios of 12C/13C. Taxonomic resolution is increased because the phytoliths examined are specific to grasses, whereas the SOM reflects the contribution of all the vegetation. Temporal resolution is increased because phytoliths are less mobile in the soil profile than SOM, and can therefore provide older dates from the same soil depth. Our results, from a desert grassland site in southwestern North America, largely confirm these expectations, and show that C4 species have dominated the grass composition for the last 8000 yr, C3 non-grass vegetation increased about 100-350 yr BP, and no significant C3 grass or non-grass vegetation existed between 350-2000 yr BP.

Original languageEnglish (US)
Pages (from-to)71-76
Number of pages6
JournalJournal of Vegetation Science
Volume11
Issue number1
DOIs
StatePublished - Feb 2000

Keywords

  • C
  • C
  • Photosynthetic pathway
  • δC

ASJC Scopus subject areas

  • Ecology
  • Plant Science

Fingerprint Dive into the research topics of 'Desert grassland dynamics estimated from carbon isotopes in grass phytoliths and soil organic matter'. Together they form a unique fingerprint.

Cite this