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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.
21

Effects of forest roads on surface and subsurface flow in southeast Alaska /

McGee, Katherine E. January 2000 (has links)
Thesis (M.S.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references (leaves 61-64). Also available via the World Wide Web.
22

Interactions between near-urban forest management and recreation : a pre- and post-harvest survey /

Balfour, Richard C. D. January 1996 (has links)
Thesis (M.S.)--Oregon State University, 1997. / Typescript (photocopy). Includes bibliographical references (leaves 149-161). Also available on the World Wide Web.
23

Ecological and morphological aspects of the breeding bird community of Blodgett Forest, California

Cohen, Yosef, January 1982 (has links)
Thesis (Ph. D.)--University of California, Berkeley, 1982. / Includes bibliographical references.
24

Assessing the conservation status of neotropical dry forests using geographical information systems and optical remote sensing

Portillo, Carlos Alonso. January 2010 (has links)
Thesis (Ph.D.)--University of Alberta, 2010. / Title from PDF file main screen (viewed on July 13, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Earth and Atmospheric Sciences, University of Alberta. Includes bibliographical references.
25

Ownership of forest land in selected parishes in Louisiana and its effect on forest conservation

Folweiler, A. D. January 1943 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1943. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 300-307).
26

Public acceptance of disturbance-based forest management : a study of the attentive public in the Central Cascades Adaptive Management Area /

Mallon, Angela L. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 71-83). Also available on the World Wide Web.
27

Optimization of forest management decision making under conditions of risk /

Lu, Fadian. January 2004 (has links) (PDF)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2004. / Thesis documentation sheet inserted. Appendix reprints four papers and manuscripts, three co-authored with others. Includes bibliographical references. Also partially available via the World Wide Web in PDF format; online version lacks appendix.
28

Scaling hydrologic impacts from road segments to a small watershed /

Royer, Timothy Adam. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 106-110). Also available on the World Wide Web.
29

What can research contribute to the prevention of forest fires? /

Matthews, Donald N. January 1939 (has links)
Thesis (Forest Engineer)--Oregon State College, 1939. / Also available on the World Wide Web.
30

A comparison of harvester productivity and stump volume waste in coppiced and planted eucalyptus grandis pulpwood compartments in the KwaZulu-Natal forestry region of South Africa

Ramantswana, Mufhumudzi Muedanyi January 2012 (has links)
Over the past decade the South African forestry industry has gradually experienced the ramifications of labour scarcity, increases in labour costs, the effect of HIV and AIDS and increasing timber demand. Consequently, this has led to an increase in the mechanisation rate, especially in timber harvesting operations. Due to the labour challenges in South Africa, mechanised forestry equipment has increasingly been required to operate in complex forest conditions, such as coppiced compartments, where they have not operated before. It therefore occurs that harvesters are either used in certain coppiced compartments with uncertain productivity expectations, or the harvesters are not used in these compartments due to a lack of productivity knowledge. The influence that certain factors have on harvester productivity and stump volume loss – factors such as coppice regeneration practices and stem form – is poorly understood and has not been quantified. No scientific research exists regarding the effects of coppice compartments on the productivity of a harvester and the amount of stump volume waste. This research aimed at determining the influence of tree volume, tree form, stem felled first and distance between stems on the productivity of an excavator based harvester in coppiced double, coppiced single and planted Eucalyptus grandis pulpwood compartments. Furthermore, the research determined whether there was any stump volume waste, and quantified how much of it was due to excessive stump heights by the harvester. Through regression analysis, productivity equations were derived to make productivity predictions in both coppiced and planted compartments. All stumps were evaluated for waste and the average stump volume waste in coppiced double, coppiced single and planted trees was determined. The research results showed that planted trees had the highest productivity across all tree sizes, followed by coppiced single trees and then coppiced double stems. When harvesting a 0.2 m3 tree, the mean harvester productivity was 8.7 m3 per PMH in coppiced double trees, 13.8 m3 per PMH in coppiced single trees and 16.1 m3 per PMH in planted trees. In coppiced double stems the productivity was not significantly influence by the distance between stems. However, the productivity was significantly influenced by the stem felled first. The regression results showed that if the smaller stem was felled first, the productivity would increase if the larger stem’s volume was less than 0.18 m3; however where the larger stem was greater than 0.18 m3, the relationship was reversed. In addition, the productivity for both coppiced single trees and coppiced double stems were significantly influenced by stem form. The poorly formed trees had low productivity compared to the trees with good form. The stump volume findings showed that coppiced double stems had the highest average stump volume waste per stump, with 0.00307 m3 waste, followed by coppiced single trees (0.001954 m3) and planted trees (0.001650 m3). The average stump volume waste per stump with waste for the planted trees was negligible. This research provides forestry companies and harvesting contractors with information on the effect of tree volume, tree form and stem felled first on harvester productivity in E. grandis coppiced double, coppiced single and planted compartments. This information will assist in making equipment and system selection decisions and improve operational management and control. In addition, they will also be aware of stump volume losses that will occur in the three scenarios.

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