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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.
11

Secondary succession of spring flora associated with windthrow pits as influenced by microtopography and light in an old-growth beech-maple forest in east-central Indiana

Gedler, Mark S. January 1998 (has links)
This research focused on the secondary succession of spring flora occurring within pits of windthrows located in the area described as Ginn/ Nixon Woods, an old growth beech-maple forest community that transitions to a mixed mesophytic forest community, approximately 12 miles north of Muncie, IN. More specifically, this research sought to identify the vegetative production capacities of pits as well as determine the extent to which pit microtopography and light influx affect the production of spring flora.In all sixty plots were established--30 test plots within the confines of windthrow pits, and 30 control plots, each one just six feet away from a test plot on undisturbed forest soil. One sampling period occurred in 1993 (just prior to leafing); four sampling periods occurred in 1994 (two prior to leafing and two after leafing). Species presence, density and cover data were used to produce two-dimensional ordinations for examination. Species presence, plot depth, slope, and light data were subjected to the Spearman Rank Order Correlation Test to determine the extent of influence pit microtopography and light influx have on spring flora.Examination of the data clearly showed that disturbed areas known as windthrow pits experience a significant decline in vegetative production--at least for a few years but likely for many years, after the initial disturbance or windthrow occurs. The data also clearly showed that over time windthrow pits eventually recover vegetative production.The recovery of vegetative production in pits was shown to have a positive correlation with plot depth; that is to say, as pit depth decreases, vegetative diversity increases. Standing water in pits, though not recorded statistically, was observed in the field as having a strong negative impact on vegetative recovery. Consequently, the environmental factors that work together to affect the topographical recovery of the pit to an elevation equal to or greater than the surrounding forest floor were found to be critical in the vegetative recovery of pits. This researcher has appropriately termed this recovery process as "elevation equilibrium," since the end result is a pit whose topographical relief has given way to a relatively static elevation equal to adjacent undisturbed areas of the forest floor.Unlike plot depth, the amount of slope in pits did not seem to play a significant role in reducing or encouraging vegetative recovery. Likewise the amount of shade cast on pits prior to leafing, and the size and/or presence of gaps in the canopy after leafing, appeared to have little influence on the recovery of spring flora. When plant diversity data for each test plot was correlated with its slope, pre-leafing light influx and post-leafinglight influx data using the Spearman Rank Order Correlation test, it found no significant relationships between any of the sets of variables. / Department of Natural Resources and Environmental Management
12

Foraging habitat selection of Ohio bats an examination between eastern second growth forest, eastern old growth forest, and pasture land /

Carter, Richard T. January 2008 (has links)
Thesis (M.S.)--Ohio University, March, 2008. / Title from PDF t.p. Includes bibliographical references.
13

Landscape patterns of pre-logging forest conditions in western Oregon /

Rasmussen, Mary C. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 1997. / Typescript (photocopy). Includes bibliographical references (leaves 43-47). Also available on the World Wide Web.
14

A canopy perspective of community dynamics of an old-growth Pseudotsuga-Tsuga forest /

Ishii, Hiroaki. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 106-116).
15

Spatial and Temporal Patterns of Natural Disturbance in Old-Growth Forests of Northern Maine, USA

Fraver, Shawn January 2004 (has links) (PDF)
No description available.
16

Five centuries of structural development in an old-growth Douglas-fir stand in the Pacific Northwest : a reconstruction from tree-ring records /

Winter, Linda Ellen. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 108-115).
17

Stem respiration in old growth forests : An investigation into spatial variation in stem respiration between old growth forests in Sweden / Stamrespiration i naturskogar : En undersökning av rumslig variation i respiration mellan naturskogar i Sverige

Nordvall, Tim January 2023 (has links)
Stem respiration is an important part of respiration coming from different dead and living stem tissues of trees, which makes an important contribution to the overall forest carbon balance. This report investigated spatial differences regarding radial diffusion of CO2 through the bark on trees across different old growth forests in Sweden. Some key environmental factors such as precipitation, wetness classes, temperature, stem diameter, distance from the coast, and latitude have been analysed to find relationships with stem respiration. Measurements were carried out on the most common tree species in Sweden, Pinus sylvestris, Picea abies and Betula pubescens. This was done by using a portable gas analyser strapped to the trees. The results show statistical differences in stem respiration for each tree species between some of the forests, while no statistical differences were found between wetness classes within or between forests. The only environmental factor that was found to have a significant relationship with stem respiration was stem diameter for P. sylvestris. Overall, these results indicate that stem respiration rate is relatively insensitive to environmental variation, which potentially simplifies the process of extrapolating this flux over space and time. Knowledge about stem respiration is important for understanding of the carbon cycle and prediction of future global change. Therefore, it is crucial to gain extensive information and understanding about the external relationships that could influence stem respiration.
18

Protecting old growth and other non-timber forest values in Idaho's state forests : a policy sciences approach for integrated natural resource management /

Feldman, Gabrielle R. January 1900 (has links)
Thesis (Ph. D., Natural Resources)--University of Idaho, October 2007. / Major professor: Jay O'Laughlin. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
19

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.
20

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

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