Spatial patterns of stand structure in Pinus ponderosa dominated forests within the Blacks Mountain Experimental Forest, California, USA, in 1930s and contemporary conditions
department or school: Forestry, Faculty of
data provider: DSpace
degree campus: UBCV
creator: Nepal, Sushil
issued: 2023-06-27T22:32:52Z
issued: 2023
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Spatial patterns of forest overstory prior to timber harvest activities associated with Euro-American settlement can serve as helpful forest reference conditions. Yet, such historical reference patterns can be challenging to quantify due to a lack of appropriate spatially explicit field data and the limitations of dendrochronological techniques. As a result, many studies have investigated contemporary spatial patterns of tree density and tree size, but few have successfully described changes in spatial patterns. In this dissertation, I first used overstory census data collected in 1934, over an area of ~4,000 ha, to characterize forest overstory reference conditions for Blacks Mountain Experimental Forest (BMEF), California, USA. Specifically, I quantified the 1934 spatial patterns of stand density index by seven vigor classes for Ponderosa pine/Jeffrey pine and white fir and incense-cedar. The forest reference conditions for BMEF consisted of clusters of open forests dominated by high vigor ponderosa pine trees associated with soil moisture and elevation gradients. Second, I used both 1934 and 2018 regeneration data from BMEF to compare the stocking between reference and contemporary conditions. The stocking of the reference conditions was dominated by ponderosa pine seedlings and was associated with available water capacity at 150 cm and overstory basal area (m2 ha-1). Third, I utilized 2016 Light Detection and Ranging data and overstory ground truth data to compare among stands that received thinning treatments, prescribed burn treatments, and a combination of thinning with prescribed burn treatments. I then compared above-ground biomass (Mg ha-1) between contemporary (2016) and reference (1934 census data) conditions. Spatial patterns in above-ground biomass were more heterogeneous in reference conditions than in contemporary conditions. However, in contemporary conditions, prescribed burns combined with thinning were better able to emulate the spatial patterns …
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/85164
note: SPATIAL PATTERNS OF STAND STRUCTURE IN PINUS PONDEROSA DOMINATED FORESTS WITHIN THE BLACKS MOUNTAIN EXPERIMENTAL FOREST, CALIFORNIA, USA, IN 1930s AND CONTEMPORARY CONDITIONS by Sushil Nepal B.Sc., Institute of Agriculture and Animal Science, 2011 M.Sc., Institute of Agriculture and Animal Sciences, 2014 M.Sc., Forestry, Northern Arizona University, 2017 A THESIS SUBMITTED IN PARTIAL FULFILMENT 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) June 2023 © Sushil Nepal, 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: Spatial patterns of stand structure in Pinus ponderosa dominated forests within the Blacks Mountain Experimental Forest, California, USA, in 1930s and contemporary conditions submitted by Sushil Nepal in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Forestry Examining Committee: Bianca N.I. Eskelson, Associate Professor, Forest Resources Management, UBC Supervisor Martin W. Ritchie, Research Forester, United States Department of Agriculture, Forest Service, Pacific Southwest Research Station Supervisory Committee Member Nicholas C. Coops, Professor, Forest Resources Management, UBC Supervisory Committee Member Sarah E. Gergel, Professor, Landscape Ecology and Conservation, UBC Supervisory Committee Member Sean M. Smukler, Associate Professor, Faculty of Land and Food Systems, UBC University Examiner Jeanine M. Rhemtulla, Associate Professor, Forest and Conservation Sciences, UBC University Examiner iii Abstract Spatial patterns of forest overstory prior to timber harvest activities associated with Euro-American settlement can serve as helpful forest reference conditions. Yet, such historical reference patterns can be challenging to quantify due to a lack of appropriate spatially ex…
has type: Thesis/Dissertation
date issued: 2023-11
is shown at: 10.14288/1.0433756
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: Eskelson, Bianca N. I.
type: Text
identifier URI: http://hdl.handle.net/2429/85164