The vegetation responses to seven silvicultural treatments one growing season after harvesting were examined on seven sites in the southern Appalachian mountains of Virginia and West Virginia. Treatments included: 1) control, 2) understory control by herbicide, 3) group selection, 4) high-leave shelterwood, 5) low-leave shelterwood, 6) leave tree, and 7) clearcut. The effects of harvesting were compared between treatments and between pre-harvest and post-harvest samplings. Species richness, percent cover, and local species extinctions were calculated for sample plots ranging in size from 1m2 to 2 ha. Vegetation richness and cover increased with increasing harvest intensity. Local species extinctions were similar in the control and disturbed treatments. Additional analyses were performed using the control, high-leave shelterwood, and clearcut on five of the seven sites to determine the relationships between soil, litter, and other environmental characteristics and vegetation in the herbaceous layer (<1 m in height). Multivariate analysis techniques were used to analyze average differences in species abundance between pre-harvest and post-harvest and to relate post-harvest vegetation to microsite characteristics. Regional-scale differences in site location were more important in explaining the presence of a species than were environmental characteristics. Within a region, species primarily were distributed along a light/litter weight gradient and secondarily along a soil properties and nutrient gradient. / Master of Science
Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/33316 |
Date | 12 June 2001 |
Creators | Hood, Sharon M. |
Contributors | Forestry, Aust, W. Michael, Smith, David William, Jones, Robert H., Zedaker, Shepard M. |
Publisher | Virginia Tech |
Source Sets | Virginia Tech Theses and Dissertation |
Detected Language | English |
Type | Thesis |
Format | application/pdf |
Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
Relation | etd.pdf |
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