Mathematical insights into mechanisms leading to coexistence and competitive exclusion among mutualist guilds
department or school: Arts and Sciences, Irving K. Barber School of (Okanagan)
department or school: Computer Science, Mathematics, Physics and Statistics, Department of (Okanagan)
data provider: DSpace
degree campus: UBCO
creator: Martignoni, Maria
issued: 2020-05-07T20:06:05Z
issued: 2020
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: In the last decades, microbial inoculants have been used as organic fertilizers worldwide. One of the most widely used commercial products are arbuscular mycorrhizal (AM) fungi, as these fungi can associate with a vast variety of crops cultivated in agriculture. Despite the potential benefits for soil quality and crop yield associated with the use of AM fungi, experiments assessing the effective establishment of the fungi in the field have given inconsistent results. Additionally, it is not yet clear whether the introduction of commercial inoculants could lead to a biodiversity loss in the native fungal community, and ultimately have a negative impact on plant growth. Here I develop a series of ordinary and partial differential equation models to discuss the establishment and regional spread of the inoculants in the field from a theoretical point of view. I use linear and nonlinear stability analysis and extensive numerical simulations to study the spatio-temporal dynamics of a guild of mutualists (the fungal species) sharing a resource provided by the same partner (the host plant), constituting a shared resource for all fungi. My results shed light on the discordant experimental observations found in the literature, and allow to assess the risks and benefit of inoculation. I identify under which conditions inoculation can effectively boost productivity, when it has no significant effect on plant growth and on the native fungal community, and when it represents an invasion risk. More generally, the models provide important ecological insights into the mechanisms responsible for coexistence and competitive exclusion among mutualist guilds, and constitute a framework to predict the consequences of species manipulation in mutualist communities. Indeed, the models I have developed are simple enough to apply to a broad range of mutualisms found in nature, such as pollination or seed dispersal.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/74372
note: MATHEMATICAL INSIGHTS INTO MECHANISMSLEADING TO COEXISTENCE AND COMPETITIVEEXCLUSION AMONG MUTUALIST GUILDSbyMaria MartignoniA DISSERTATION SUBMITTED IN PARTIAL FULFILLMENT OFTHE REQUIREMENTS FOR THE DEGREE OFDOCTOR OF PHILOSOPHYinTHE COLLEGE OF GRADUATE STUDIES(Mathematics)THE UNIVERSITY OF BRITISH COLUMBIA(Okanagan)April 2020c©Maria Martignoni, 2020The following individuals certify that they have read, and recommend to the Faculty ofGraduate and Postdoctoral Studies for acceptance, the dissertation entitled:Mathematical insights into mechanisms leading to coexistence and competitive exclusionamong mutualist guildssubmitted by Maria Martignoni in partial fulfillment of the requirements for the degreeof Doctor of Philosophy in Mathematics.Examining Committee:Prof. Rebecca Tyson, MathematicsSupervisorDr. Jimmy Garnier, MathematicsCo-SupervisorDr. Miranda Hart, BiologySupervisory Committee MemberDr. Dan Vollick, PhysicsSupervisory Committee MemberProf. Cigdem Eskicioglu, EngineeringUniversity ExaminerProf. Alan Hastings, MathematicsExternal ExamineriiAbstractIn the last decades, microbial inoculants have been used as organic fertilizers worldwide.One of the most widely used commercial products are arbuscular mycorrhizal (AM) fungi,as these fungi can associate with a vast variety of crops cultivated in agriculture. Despitethe potential benefits for soil quality and crop yield associated with the use of AM fungi,experiments assessing the effective establishment of the fungi in the field have given in-consistent results. Additionally, it is not yet clear whether the introduction of commercialinoculants could lead to a biodiversity loss in the native fungal community, and ultimatelyhave a negative impact on plant growth. Here I develop a series of ordinary and partialdifferential equation models to discuss the establishment and regional spread of the inoc-ulants in the field from a theoretical point of view. I use linear and nonlinear stabilityanalysis and extensive numer…
has type: Thesis/Dissertation
date issued: 2020-05
is shown at: 10.14288/1.0390425
language: eng
degree discipline: Mathematics
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-ShareAlike 4.0 International
rights URI: http://creativecommons.org/licenses/by-sa/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/74372