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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Biologic activity in two western Oregon Douglas-fir stands : a research link to management /

Hope, Sharon Margaret. January 1995 (has links)
Thesis (M.S.)--Oregon State University, 1996. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
32

Tree species-soils relationships in old-growth forests of the Oregon Coast Range /

Cross, Alison. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 42-54). Also available on the World Wide Web.
33

Old growth forest preservation in British Columbia and the American Pacific Northwest : an account of a debate for survival

Waatainen, Jeffrey Bernard 11 1900 (has links)
This essay offers a study of old growth forest policy in British Columbia and the American Pacific Northwest and, in so doing, attempts to contribute to the sparse comparative environmental literature that uses Canada as a case study. Specifically, the essay addresses the question of why old growth forest preservation policy divergences so dramatically between British Columbia and the American Pacific Northwest. After establishing that American Pacific Northwest and British Columbia old growth forest preservation policy diverges, the author employs a chronological methodology to reconstruct the current old growth preservation policy outcomes in both jurisdictions. The author then identifies a series of variables that affect old growth forest preservation policy in both jurisdictions, and examines each as a force of divergence. The essay discusses the different influences of two non-institutional variables-science and economics-and two institutional variables-federalism and legalism-on American Pacific Northwest and British Columbia old growth policy. The essay concludes by discussing the question of how each variable works with one another to produce this instance of policy divergence. The author finds that all four variables collaborate with one another and contribute to the divergence. However, the essay concludes that the major determining factor in this case of policy divergence is the interplay of the two institutional variables.
34

Vegetation dynamics and response to disturbance, in floodplain forest ecosystems with a focus on lianas

Allen, Bruce Peter, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 160-168).
35

Old growth forest preservation in British Columbia and the American Pacific Northwest : an account of a debate for survival

Waatainen, Jeffrey Bernard 11 1900 (has links)
This essay offers a study of old growth forest policy in British Columbia and the American Pacific Northwest and, in so doing, attempts to contribute to the sparse comparative environmental literature that uses Canada as a case study. Specifically, the essay addresses the question of why old growth forest preservation policy divergences so dramatically between British Columbia and the American Pacific Northwest. After establishing that American Pacific Northwest and British Columbia old growth forest preservation policy diverges, the author employs a chronological methodology to reconstruct the current old growth preservation policy outcomes in both jurisdictions. The author then identifies a series of variables that affect old growth forest preservation policy in both jurisdictions, and examines each as a force of divergence. The essay discusses the different influences of two non-institutional variables-science and economics-and two institutional variables-federalism and legalism-on American Pacific Northwest and British Columbia old growth policy. The essay concludes by discussing the question of how each variable works with one another to produce this instance of policy divergence. The author finds that all four variables collaborate with one another and contribute to the divergence. However, the essay concludes that the major determining factor in this case of policy divergence is the interplay of the two institutional variables. / Arts, Faculty of / Political Science, Department of / Graduate
36

Community structure and composition changes of two old-growth forests at Versailles State Park in southeastern Indiana

Behforouz, Kavon Benjamin 04 May 2013 (has links)
In the 1950’s and 1960’s, studies of two old-growth forest stands in Versailles State Park, Laughery Bluff and Dogwood Nature Preserves, were designed and carried out by Potzger to provide the baseline necessary to investigate future trends in these forest communities. In 1968 and 1988, Jackson surveyed these stands again and identified changes in attributes and size classes over that 20-year period. In 2011 and 2012, these sites were re-sampled to document change in species composition and stand structure since 1968. Diameter at breast height (dbh) and species identification were recorded for all stems with dbh ≥ 10 cm. Trees between 1 and 9.9 cm dbh were sampled by counting the number of individuals by species. These data were used to calculate density, dominance, and importance values, as well as to provide full-census data on the overstory size classes at the two sites. Notable findings since the prior studies included the continued increase of Acer saccharum in density and basal area as well as the continued loss of Cornus florida and Fagus grandifolia stems throughout both stands. / Department of Biology
37

Regeneration responses to management for old-growth characteristics in northern hardwood-conifer forests

Gottesman, Aviva Joy 01 January 2017 (has links)
Silviculture practices interact with multiple sources of variability to influence regeneration trends in northern hardwood forests. There is uncertainty whether low-intensity selection harvesting techniques will result in desirable tree regeneration. Our research is part of a long-term study that tests the hypothesis that a silvicultural approach called "structural complexity enhancement" (SCE) can promote accelerated development of late-successional forest structure and functions. Our objective is to understand the regeneration dynamics following three uneven-aged forestry treatments modified to increase postharvest structural retention: single-tree selection, group selection, and SCE. In terms of regeneration densities and composition, how do light availability, competition, seedbad, and herbivory interact with overstory treatment effects? To explore these relationships, manipulations and controls were replicated across 2-hectare treatment units at two sites in Vermont, USA. Forest inventory data were collected pre-harvest and 13 years post-harvest. We used linear mixed effects models with repeated measures to evaluate the effects of treatment on seedling and sapling abundances and diversity (Shannon-Weiner H'). Multivariate analyses evaluated the relative predictive strength of treatment versus alternative sources of ecological variability. Thirteen-years post-harvest, the harvested treatments were all successful in recruiting a sapling class with a significantly higher mean than the control. However, in all of the treatments prolific beech regeneration dominated the understory in patches. Seedling densities exhibited pulses of recruitment and mortality with a significant positive treatment effect on all harvested treatments in the first four years post-harvest. Seedling diversity was maintained, while sapling diversity was negatively influenced by herbivory (deer and moose browse) and leaf litter substrate. Multivariate analyses suggest that while treatment had a dominant effect, other factors were strongly influential in driving regeneration responses. Results indicate variants of uneven-aged systems that retain or enhance stand structural complexity, including old-growth characteristics, generally regenerate at adequate and desirable densities depending on site conditions.
38

Tree-Ring Dating Of Old-Growth Longleaf Pine (Pinus Palustris Mill.) Logs From An Exposed Timber Crib Dam, Hope Mills, North Carolina, U.S.A.

Van De Gevel, Saskia L., Hart, Justin L., Grissino-Mayer, Henri D., Robinson, Kenneth W. 01 1900 (has links)
On 26 May 2003, intense rainfall from a series of thunderstorms in eastern North Carolina caused flooding that eventually destroyed the concrete dam in Hope Mills, draining Hope Mills Lake, and revealing a formerly submerged and buried structure that was identified as a timber crib dam. Inspection revealed these logs to be old-growth longleaf pines, which are now rare on the coastal plain landscape. Our primary objective was to develop a new multi-century longleaf pine tree-ring chronology by crossdating the tree rings from sections extracted from logs in the crib dam with an anchored tree-ring chronology created from nearby living longleaf pine trees. We also examined the climatic response in the longleaf pine trees to evaluate their potential for reconstructing climate. Using tree-ring measurements obtained from old-growth longleaf pines found at a nearby church, we were able to date the rings on 21 series representing 14 logs from the crib dam, spanning the years 1597 to 1825. Distorted sapwood in many of the logs prevented us from finding absolute cutting dates and lessened the strength of correlation during the period of overlap between the church series and crib dam series. Human disturbances, specifically related to the naval stores industry, likely influenced the growth-ring patterns of the crib dam pine samples, as well. Correlation analyses between the longleaf pine chronology and temperature, precipitation, Palmer Drought Severity Indices, and North Atlantic sea surface temperatures showed a significant response to cool and wet spring months.
39

Stand dynamics of an old-growth hemlock-hardwood forest in West Virginia

Beane, Nathan R. January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 55 p. : ill., maps. Includes abstract. Includes bibliographical references (p. 47-50).
40

The forest composition and the pedology of the undisturbed soils in an old-growth virgin beech-maple forest in east-central Indiana

McClain, Mark Stephen 03 June 2011 (has links)
The edaphic and pedologic factors of forest soils and their influence on the naturally occurring climax vegetation in an old-growht forest in east-central Indiana were examined. The northern portion of this woods is a virgin remnant of the presettlement forest that Braun (1950) described as the BeechMaple Forest Region. This remnant is best classified as a sugar maple-American beech-slippery elm association. The undisturbed soils found were the moderately well drained Glynwood soils (Aquic Hapludalfs, fine, illitic, mesic), the somewhat poorly drained Blount soils (Aeric Ochraqualfs, fine, illitic, mesic), the poorly drained Lenawee Variant soils (Typic Haplaquepts, fine, nonacid, mixed,mesic), and the very poorly drained Lenawee (taxajunct) soils (Mollic Haplaquepts, fine-loamy, nonacid, mixed, mesic). The seasonal high water table and internal soil drainage of the soils appear to influence the survival and importance of the dominant tree species. There were 25 tree species sampled.The three most important tree species were sugar maple (Acer saccharum, Marsh.), American beech (Fagus qrandifolia Ehrh.), and slippery elm (Ulmus rubra Muhl.)on the Blount, Glynwood, and Lenawee Variant soils. The fourth most important tree species was silver maple (Acer saccharinum L.) which was restricted to the lowland-depressional forest type (Lindsey and Schmelz, 1970) inclusion represented by the Lenawee (taxajunct) soils. The distribution of tree species occurring on each of the four soils was statistically examined at the 0.05 level of significance. Sugar maple had a significantly higher mean average basal area on the Glynwood soils; American beech had a significantly higher average number of trees on the Blount soils; and slippery elm had a significantly higher proportion of trees on the Glynwood soils.Ball State UniversityMuncie, IN 47306

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