Home

Browse
Communities
& Collections

Issue Date
Author
Title
Subject

Sign on to:

My Account
authorized users

Edit Profile

Help
 Please use this identifier to cite or link to this item: http://hdl.handle.net/1807/478

 Title: The effect of NPK fertilization for nine years on boreal forest vegetation in northwestern Canada Authors: Turkington, RoyElizabeth, JohnKrebs, CharlesDale, M.R.T.Nams, V.O.Boonstra, RudyBoutin, S.Martin, K.Sinclair, A.R.E.Smith, J.N.M. Keywords: Cone crop; Growth rate; Plant productivity; Seed production; Transient dynamics Issue Date: 1998 Publisher: Opulus Press Uppsala Citation: Journal of Vegetation Science 9: 333-346, 1998 Abstract: Plant productivity is limited by mineral nutrient availability in many boreal forest ecosystems. This study is an analysis of the growth responses of components of a boreal plant community (cryptogams, herbaceous and woody perennials, the dominant shrubs Salix glauca (grey willow) and Betula glandulosa (bog birch) and the dominant tree Picea glauca (white spruce), to the addition of an NPK fertilizer over a nine- year period. The study was carried out in a low-nutrient boreal forest ecosystem in the Yukon territory in northwestern Canada. The following predictions were tested: (1) that there would be an overall increase in abundance (measured either as cover, density, or dry mass) of all components of the vegetation, (2) that vegetation composition would change as more competitive species increased in abundance and (3) that initial community changes in response to fertilization would be transient. In general, all predictions were found to be true. Species composition changed rapidly in response to fertilizer. Graminoids (e.g. F estuca altaica) and some dicots (e.g. Mertensia paniculata and Achillea millefolium) increased in cover, while other dicots (e.g. Anemone parviflora), dwarf shrubs (e.g. Arctostaphylos uva- ursi), bryophytes and lichens declined. There was a significant increase in the growth rate of the two dominant shrubs and of Picea, but not in the cone crop or seed production by Picea. Surveys after 1 or 2 years showed responses by the vegetation but more stable patterns of response did not emerge until after 5 or 6 years. There were consistent and directional changes in the percent cover of some of the herbaceous species on control plots. Growth rates of Salix and Betula varied considerably from year to year, independently of treatment. Long-term studies are essential if we are to understand the role of nutrient limitation in this ecosystem. URI: http://hdl.handle.net/1807/478 Appears in Collections: Biology

Files in This Item:

File Description SizeFormat