Dry grasslands in Wood Buffalo National Park: reply

In examining dry grassland areas of Wood Buffalo National Park (WBNP), we used vascular plant indicators commonly found in the grassland landscapes in the southern and central parts of the Prairie Provinces. With distance northward the landscapes become increasingly tree-dominated and the dry grassl...

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Bibliographic Details
Published in:Canadian Journal of Botany
Main Authors: Schwarz, A G, Wein, Ross W
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1999
Subjects:
Online Access:http://dx.doi.org/10.1139/b99-121
http://www.nrcresearchpress.com/doi/pdf/10.1139/b99-121
Description
Summary:In examining dry grassland areas of Wood Buffalo National Park (WBNP), we used vascular plant indicators commonly found in the grassland landscapes in the southern and central parts of the Prairie Provinces. With distance northward the landscapes become increasingly tree-dominated and the dry grasslands have fewer dry grassland indicator species (about 40 in the area of WBNP) and become smaller in size (about 1 ha in WBNP). Key species are Stipa comata Trin & Rupr., Stipa curtiseta (A.S. Hitchc.) Barkworth, and Stipa columbiana Macoun on the drier sites. Paleontological records and historical documents suggest that these remnant dry grasslands must expand during decades of drought and must contract during decades of higher summer rainfall. We hypothesize that fires might enhance dry grassland expansion by stressing and killing trees and shrubs. Southern dry grassland vascular plant species represent over 7% of the total in WBNP. It is reasonable to hypothesize that these represent special ecotypes that deserve special protection through prescribed burning.Key words: remnant grasslands, Stipa spp., climate change.