Countergradient variation in lodgepole pine flowering phenology
department or school: Forestry, Faculty of
data provider: DSpace
degree campus: UBCV
creator: Tysor, Carolyn Susannah
issued: 2025-02-03T15:03:15Z
issued: 2025
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: The timing and duration of pollen shed and cone receptivity in lodgepole pine (Pinus contorta) influence its fecundity, levels of gene flow, and local adaptation. Accurate predictions of spring reproductive (“flowering”) phenology are essential for understanding local adaptation, gene flow, population structure, and climate change impacts. Using 16 years of data from lodgepole pine sourced from across British Columbia and grown at seven seed orchard sites in an approximate common garden design, I developed a multilevel Bayesian model to assess the forcing requirements for flowering onset and cessation, and the provenance effects on these requirements for both male and female strobili. The model reveals a countergradient pattern in flowering: populations from warm locations require more forcing by warm temperatures than those from colder locations. This countergradient effect should result in increased overlap among populations at the landscape level but decreased overlap within individual seed orchards. Pollen shed typically begins shortly before and ends slightly after receptivity. By applying the model to historical and predicted daily temperature records, I estimated flowering phenology for diverse provenances at multiple sites from 1945 to 2100, translating forcing predictions into specific days of the year. Historical flowering patterns are variable but show significant correlations across distant sites. Under moderate climate change scenarios, flowering is predicted to advance by two to three weeks without having appreciable impacts on synchrony.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/90260
note: Countergradient variation inlodgepole pine flowering phenologybyCarolyn Susannah TysorB.Sc., Northern Arizona University, 2010A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THEREQUIREMENTS FOR THE DEGREE OFMASTER OF SCIENCEinThe Faculty of Graduate and Postdoctoral Studies(Forestry)THE UNIVERSITY OF BRITISH COLUMBIA(Vancouver)January 2025© Carolyn Susannah Tysor, 2025The following individuals certify that they have read, and recommend to the Faculty of Graduate andPostdoctoral Studies for acceptance, the thesis entitled:Countergradient variation in lodgepole pine flowering phenologysubmitted by Carolyn Susannah Tysor in partial fulfillment of the requirements forthe degree of Master of Sciencein ForestryExamining Committee:Sally Aitken, Professor, Department of Forest and Conservation Sciences, UBCSupervisorElizabeth Wolkovich, Associate Professor, Department of Forest and Conservation Sciences, UBCSupervisory Committee MemberMichael Whitlock, Professor, Department of Zoology, UBCSupervisory Committee MemberSean Michaletz, Assistant Professor, Department of Botany, UBCAdditional ExamineriiAbstractThe timing and duration of pollen shed and cone receptivity in lodgepole pine (Pinus contorta) influence itsfecundity, levels of gene flow, and local adaptation. Accurate predictions of spring reproductive (“flowering”)phenology are essential for understanding local adaptation, gene flow, population structure, and climatechange impacts. Using 16 years of data from lodgepole pine sourced from across British Columbia andgrown at seven seed orchard sites in an approximate common garden design, I developed a multilevel Bayesianmodel to assess the forcing requirements for flowering onset and cessation, and the provenance effects on theserequirements for both male and female strobili. The model reveals a countergradient pattern in flowering:populations from warm locations require more forcing by warm temperatures than those from colder locations.This countergradient effect should r…
has type: Thesis/Dissertation
date issued: 2025-05
is shown at: 10.14288/1.0447901
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: Aitken, Sally N.
type: Text
identifier URI: http://hdl.handle.net/2429/90260