Phytoliths as indicators of plant community change A case study of the reconstruction of the historical extent of the oak savanna in the Willamette Valley Oregon, USA》.pdfVIP

Catena 132 (2015) 89–96 Contents lists available at ScienceDirect Catena j ournal homepa ge: /l ocate/ catena Phytoliths as indicators of plant community change: A case study of the reconstruction of the historical extent of the oak savanna in the Willamette Valley Oregon, USA Renske P.J. Kirchholtes a,b,⁎, J.M. van Mourik c, B.R. Johnson d a Department of Integrative Biology, University of California, Berkeley, USA b University of California Museum of Paleontology, USA c Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, The Netherlands d Department of Landscape Architecture, University of Oregon, USA a r t i c l e i n f o a b s t r a c t Article history: The Oregon white oak savanna, once common in Oregons Willamette Valley, has been reduced to less than 1% of Received 4 June 2014 its former extent. For ecological restoration purposes, we used phytolith analysis to establish both historical Received in revised form 31 October 2014 vegetation composition and structure at the Jims Creek research site in Oregon, USA. We sampled the soil at Accepted 3 November 2014 47 selected plots, extracted the phytoliths, and determined the composition of the phytolith assemblages. Available online 5 December 2014 Based on the ratios of grass and tree phytoliths in the samples, each site was assigned to one of three ecotopes that, through phytoliths, describe