The impact of altitude, soil geology, and soil depth on Pinus patula solid wood properties for structural timber and plywood production
department or school: Forestry, Faculty of
data provider: DSpace
degree campus: UBCV
creator: van der Merwe, Jaco-Pierre
issued: 2023-10-19T23:51:38Z
issued: 2023
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Climate is known to impact the growth of plantation forests in South Africa. To characterize the conditions, this study developed temperature and rainfall models for specific plantations in the Lowveld Escarpment and Highveld forestry regions of South Africa. The local climate models use a finer scale than world climate models, and they improve the understanding of how terrain features impact regional climate and historic tree growth. In addition, the finer scale models give insights into the relationship between the local terrain condition and regional climate. Plantation forests were originally established in South Africa to meet an increasing demand for solid wood products as there was a limited supply from native forests. The majority of the commercial softwood plantations were established with Mexican Pinus patula. Since growing conditions are known to impact tree growth, tree form, and wood quality of P. patula, sample plots were established over a cross-section of plantations in the Lowveld Escarpment and Highveld forestry regions of South Africa that covered an array of geologies and altitudes. Soil, growing days, and temperature were found to have little impact on tree form and wood properties. However, rainfall and specifically, spring rainfall, was found to have a highly significant impact on late wood formation, proportion of juvenile core, and wood density. In addition, tree height was found to be strongly correlated with maximum annual temperature. Veneer derived from Lowveld trees had more splitting, which was largely related to defects. Larger trees also had a greater volumetric heartwood percentage and had a smaller live crown height portion, compared to smaller trees. Highveld trees also had greater net veneer recovery and produced better quality veneer than trees grown on the Lowveld. Annual maximum temperature and tree height had a negative relationship with the recovered lumber properties and dimensional stability. Spring rainfall appears to be …
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/86238
note: THE IMPACT OF ALTITUDE, SOIL GEOLOGY, AND SOIL DEPTH ON PINUS PATULA SOLID WOOD PROPERTIES FOR STRUCTURAL TIMBER AND PLYWOOD PRODUCTION by Jaco-Pierre van der Merwe B.Sc., Stellenbosch University, 2011 M.Sc., Stellenbosch University, 2013 A thesis submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Forestry) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) October 2023 © Jaco-Pierre van der Merwe, 2023 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the dissertation entitled: The impact of altitude, soil geology, and soil depth on Pinus patula solid wood properties for structural timber and plywood production Submitted by Jaco-Pierre van der Merwe in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Forestry Examining committee: Shawn D. Mansfield, Professor, Department of Wood Science, UBC Supervisor Stavros Avramidis, Professor, Department of Wood Science, UBC Supervisory Committee Member Julie Cool, Associate Professor, Department of Wood Science, UBC Supervisory Committee Member Simon Ellis, Associate Professor, Department of Wood Science, UBC Supervisory Committee Member Gary Bull, Professor, Department of Forest Resources Management, UBC University Examiner Tony Bi, Professor, Department of Chemical and Biological Engineering, UBC University Examiner Alexis Achim, Professor, Department of Wood and Forest Sciences, Laval University External Examiner iii Abstract Climate is known to impact the growth of plantation forests in South Africa. To characterize the conditions, this study developed temperature and rainfall models for specific plantations in the Lowveld Escarpment and Highveld forestry regions of South Africa. The local climate models use a finer scale than world climate models, and they improve the understanding of how terrain features impact…
has type: Thesis/Dissertation
date issued: 2023-11
is shown at: 10.14288/1.0437241
language: eng
degree discipline: Forestry
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Mansfield, Shawn D., 1969-
type: Text
identifier URI: http://hdl.handle.net/2429/86238