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TP064

Composition, structure, and dynamics of forest and meadow communities in the Three Sisters Wilderness Area/Biosphere Reserve, 1981-2009

  • Creator(s): Charles B. Halpern
  • PI(s): Charles B. Halpern
  • Originator(s): Charles B. Halpern
  • Other researcher(s): Jerry F. Franklin, Bradley G. Smith, Ryan D. Haugo, Eric A. Miller
  • Dates of data collection: Jul 1 1981 - Sep 9 2009
  • Data collection status: Study collection is completed and no new collection is planned
  • Data access: Online
  • DOI: https://doi.org/10.6073/pasta/64e11326ef222c4815eed02edd725c17
  • Last update: Apr 9 2003 (Version 2)
<Citation>     <Acknowledgement>     <Disclaimer>    
Halpern, C. 2003. Composition, structure, and dynamics of forest and meadow communities in the Three Sisters Wilderness Area/Biosphere Reserve, 1981-2009. Long-Term Ecological Research. Forest Science Data Bank, Corvallis, OR. [Database]. Available: http://andlter.forestry.oregonstate.edu/data/abstract.aspx?dbcode=TP064. https://doi.org/10.6073/pasta/64e11326ef222c4815eed02edd725c17. Accessed 2024-12-10.
Data were provided by the HJ Andrews Experimental Forest research program, funded by the National Science Foundation's Long-Term Ecological Research Program (DEB 2025755), US Forest Service Pacific Northwest Research Station, and Oregon State University.
While substantial efforts are made to ensure the accuracy of data and documentation, complete accuracy of data sets cannot be guaranteed. All data are made available "as is". The Andrews LTER shall not be liable for damages resulting from any use or misinterpretation of data sets.
ABSTRACT:
The Three Sisters Wilderness Area is a UNESCO Biosphere Reserve representing the northern half of the Sierra-Cascade Province. It encompasses nearly 100,000 ha of largely undisturbed landscape straddling the crest of the central Cascade Range in Oregon. The Three Sisters was given wilderness status in 1957 and selected as a Biosphere Reserve in 1974 to represent a "control" area for the nearby H. J. Andrews Experimental Forest Biosphere Reserve. Coniferous forests dominate the reserve, although it supports a diversity of non-forest habitats, including montane and subalpine meadows. Integral to the establishment of a Biosphere Reserve is the collection of baseline data on the composition, structure, and distribution of its major plant communities. These baseline data are essential to monitoring both natural vegetation change and changes attributable to human activities. At the time this study was initiated (1981), basic ecological research in the Three Sisters had been limited. The goals of this study were two-fold: (1) to undertake a phytosociological analysis of the diversity of forest and non-forest plant communities and their relationships to the physical environment; and (2) to assess historical and ongoing changes in vegetation across natural forest-meadow boundaries (or ecotones). Studies addressing this second goal included a retrospective analysis of historical patterns of tree invasion as they relate to site environment, grazing history, and climate; and an analysis of subsequent changes in vegetation (1983-2009) including both tree and ground-layer communities.

Study Description Taxonomic Hierarchy Download Study Location Information: (CSV)
ENTITY TITLES:
1Forest reconnaissance plots: environmental characteristics (Jun 23 1981 - Sep 4 1981)METADATAData not online
Forest reconnaissance plots: landform, topographic and soil characteristics; UTMs
2Meadow reconnaissance plots: environmental characteristics (Jul 10 1982 - Oct 6 1982)METADATAData not online
Meadow reconnaissance plots: landform, topography, and soil characteristics
3Forest reconnaissance plots: ground conditions and growth form cover (Jun 23 1981 - Sep 4 1981)METADATAData not online
Meadow reconnaissance plots: landform, topography, and soil characteristics
4Meadow reconnaissance plots: ground conditions and growth form richness and cover (Jul 10 1982 - Oct 6 1982)METADATAData not online
Meadow reconnaissance plots: ground-surface cover; growth-form cover and richness
5Forest reconnaissance plots: species cover (Jun 23 1981 - Sep 4 1981)METADATAData not online
Forest reconnaissance plots: cover of individual plant species
6Meadow reconnaissance plots: species cover (Jul 10 1982 - Oct 6 1982)METADATAData not online
Meadow reconnaissance plots: cover of individual plant species
7Forest reconnaissance plots: prism-plot stem counts (Jun 23 1981 - Sep 4 1981)METADATAData not online
Forest reconnaissance plot stem counts: used to estimate live and dead tree density and basal area
8Forest reconnaissance plots: tree increment core, age, and height data (Jun 23 1981 - Sep 4 1981)METADATAData not online
Forest reconnaissance plot increment cores: core length, ring count, and estimated tree age
9Forest reconnaissance plots: soil depth, physical characteristics, and pH (Jul 10 1982 - Oct 6 1982)METADATAData not online
Forest reconnaissance plots: soil depth, texture, stoniness, and pH
10Meadow reconnaissance plots: soil depth and physical characteristics (Jul 10 1982 - Oct 6 1982)METADATAData not online
Meadow reconnaissance plots: soil depth, texture, and stoniness
11Forest-meadow ecotone transects: Transect bearings, lengths, UTMs, and elevations (Aug 2 1983 - Sep 20 1983)METADATAData not online
Forest-meadow ecotone transects: bearing, length, and UTMs and elevations of transect start and end points
12Forest-meadow ecotone transects: Transect topography, vegetation types, and soil characteristics (Aug 2 1983 - Sep 9 2009)METADATAData not online
Forest-meadow ecotone transects: vegetation type, physical environment, and soil characteristics at points along the forest-meadow gradient (1983)
13Forest-meadow ecotone transects: tree increment core, age, and height data (Aug 2 1983 - Sep 20 1983)METADATAData not online
Forest-meadow ecotone transect increment cores: core length, ring count, and estimated tree age in (1983; tagged trees only)
14Forest-meadow ecotone transects: tree spatial location, size, and age at the time of sampling (Aug 2 1983 - Sep 9 2009)METADATAData not online
Forest-meadow ecotone transects: tree location, diameter, height, and age along the forest-meadow gradient
15Forest-meadow ecotone transects: cover of plant species, growth forms, and ground-surface conditions (Aug 2 1983 - Sep 9 2009)METADATAData not online
Forest-meadow ecotone transects: cover of plant species, growth forms, and ground-surface conditions along the forest-meadow gradient

RELATED MATERIALS:
 TSBR topo maps with reconnaissance plot and ecotone transect locations - PDF file of USGS topographic maps showing locations of all reconnaissance plots and forest-meadow ecotone transects (13MB)
 TSBR ecotone transect directions and details - PDF file of directions to, and site-specific details for, each of the 21 permanent ecotone transects (4MB)
 TSBR aerial photos of ecotone transects - PDF file of aerial and ground-based photos of permanent ecotone transects (from Haugo dissertation (2010), Appendix C) (8MB)
 TSBR repeat photos of ecotone transects - Zip file of repeat photos of each of the ecotone transects from fixed points along or adjacent to each transect (photo dates: 1983, 1993, and 2009) (84MB)
 TP064 tree sampling history - Excel spreadsheet detailing how trees were sampled along each ecotone transect in each year. Belt widths vary within transects for trees of differing age or size class.

RELATED PUBLICATIONS:
 Haugo, Ryan D., Halpern, Charles B., Bakker, Jonathan D. 2011, Landscape context and long-term tree influences shape the dynamics of forest-meadow ecotones in mountain ecosystems (Pub. No: 4680)
 Haugo, Ryan D. 2010, Causes and consequences of conifer invasion into Pacific Northwest grasslands (Pub. No: 4640)
 Halpern, C. B. 2000, Montane and subalpine meadows of the Three Sisters Wilderness Area/Biosphere Reserve, Oregon: a community classification and gradient analysis [Abstract] (Pub. No: 3042)
 Miller, Eric A., Halpern, Charles B. 1998, Effects of environment and grazing disturbance on tree establishment in meadows of the central Cascade Range, Oregon, USA (Pub. No: 2325)
 Miller, Eric A. 1995, The dynamics of forest-meadow ecotones in the Three Sisters Wilderness, Oregon: variation across environmental gradients (Pub. No: 2179)
 Halpern, Charles B., Smith, Bradley G., Franklin, Jerry F. 1991, Forest and meadow communities of the Three Sisters Biosphere Reserve (Pub. No: 957)
 Halpern, Charles B., Smith, Bradley G., Franklin, Jerry F. 1984, Composition, structure, and distribution of the ecosystems of the Three Sisters Biosphere Reserve/Wilderness Area (Pub. No: 1323)