Management and impact of a native invasive species: Allocasuarina huegeliana in the sandplain heath of the Western Australian Wheatbelt

Nancy Shackelford

    Research output: ThesisMaster's Thesis

    Abstract

    Invasive species have been a growing concern over the last few decades. Current research focuses almost entirely on non-native species invasion, with many arguing that origin of a species is a primary factor in determining management status. In the face of wide-spread, dramatic anthropogenic change, however, native species have been found to experience swift range expansion and have many of the same undesirable impacts on the systems in which they originate; thus, some argue for impact assessment as the driver of species management. In this thesis, I aim first to find a theoretical middle ground that utilizes both origin and impact in determining the appropriateness of species management. I then focus on a native Western Australian tree Allocasuarina huegeliana invading into adjacent heathlands. This study was guided by previous work and management concerns that the invasion, thought to be caused by shifting fire regimes, is decreasing heathland diversity. I quantified the strength of the relationships between the invasion, shifted fire regimes, and biodiversity through observational study of A. huegeliana densities, time since last fire, and species loss in eleven individual heath patches. I found a strong relationship between the invasion and species loss, supporting the hypothesis that A. huegeliana is a driver of ecological change in invaded systems. I then used simulation modeling to examine the effect of fire and other management tactics on A. huegeliana population spread. I found that fire-based management is potentially a viable control method, though current return intervals are inadequate.
    LanguageEnglish
    QualificationMasters
    StateUnpublished - 2012

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    invasive species
    heathland
    range expansion
    native species
    biodiversity
    modeling
    simulation
    loss

    Cite this

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    title = "Management and impact of a native invasive species: Allocasuarina huegeliana in the sandplain heath of the Western Australian Wheatbelt",
    abstract = "Invasive species have been a growing concern over the last few decades. Current research focuses almost entirely on non-native species invasion, with many arguing that origin of a species is a primary factor in determining management status. In the face of wide-spread, dramatic anthropogenic change, however, native species have been found to experience swift range expansion and have many of the same undesirable impacts on the systems in which they originate; thus, some argue for impact assessment as the driver of species management. In this thesis, I aim first to find a theoretical middle ground that utilizes both origin and impact in determining the appropriateness of species management. I then focus on a native Western Australian tree Allocasuarina huegeliana invading into adjacent heathlands. This study was guided by previous work and management concerns that the invasion, thought to be caused by shifting fire regimes, is decreasing heathland diversity. I quantified the strength of the relationships between the invasion, shifted fire regimes, and biodiversity through observational study of A. huegeliana densities, time since last fire, and species loss in eleven individual heath patches. I found a strong relationship between the invasion and species loss, supporting the hypothesis that A. huegeliana is a driver of ecological change in invaded systems. I then used simulation modeling to examine the effect of fire and other management tactics on A. huegeliana population spread. I found that fire-based management is potentially a viable control method, though current return intervals are inadequate.",
    keywords = "Native invasion, Management, Biodiversity loss, Woody encroachment, Simulation modeling, Kwongan",
    author = "Nancy Shackelford",
    year = "2012",
    language = "English",

    }

    TY - THES

    T1 - Management and impact of a native invasive species: Allocasuarina huegeliana in the sandplain heath of the Western Australian Wheatbelt

    AU - Shackelford,Nancy

    PY - 2012

    Y1 - 2012

    N2 - Invasive species have been a growing concern over the last few decades. Current research focuses almost entirely on non-native species invasion, with many arguing that origin of a species is a primary factor in determining management status. In the face of wide-spread, dramatic anthropogenic change, however, native species have been found to experience swift range expansion and have many of the same undesirable impacts on the systems in which they originate; thus, some argue for impact assessment as the driver of species management. In this thesis, I aim first to find a theoretical middle ground that utilizes both origin and impact in determining the appropriateness of species management. I then focus on a native Western Australian tree Allocasuarina huegeliana invading into adjacent heathlands. This study was guided by previous work and management concerns that the invasion, thought to be caused by shifting fire regimes, is decreasing heathland diversity. I quantified the strength of the relationships between the invasion, shifted fire regimes, and biodiversity through observational study of A. huegeliana densities, time since last fire, and species loss in eleven individual heath patches. I found a strong relationship between the invasion and species loss, supporting the hypothesis that A. huegeliana is a driver of ecological change in invaded systems. I then used simulation modeling to examine the effect of fire and other management tactics on A. huegeliana population spread. I found that fire-based management is potentially a viable control method, though current return intervals are inadequate.

    AB - Invasive species have been a growing concern over the last few decades. Current research focuses almost entirely on non-native species invasion, with many arguing that origin of a species is a primary factor in determining management status. In the face of wide-spread, dramatic anthropogenic change, however, native species have been found to experience swift range expansion and have many of the same undesirable impacts on the systems in which they originate; thus, some argue for impact assessment as the driver of species management. In this thesis, I aim first to find a theoretical middle ground that utilizes both origin and impact in determining the appropriateness of species management. I then focus on a native Western Australian tree Allocasuarina huegeliana invading into adjacent heathlands. This study was guided by previous work and management concerns that the invasion, thought to be caused by shifting fire regimes, is decreasing heathland diversity. I quantified the strength of the relationships between the invasion, shifted fire regimes, and biodiversity through observational study of A. huegeliana densities, time since last fire, and species loss in eleven individual heath patches. I found a strong relationship between the invasion and species loss, supporting the hypothesis that A. huegeliana is a driver of ecological change in invaded systems. I then used simulation modeling to examine the effect of fire and other management tactics on A. huegeliana population spread. I found that fire-based management is potentially a viable control method, though current return intervals are inadequate.

    KW - Native invasion

    KW - Management

    KW - Biodiversity loss

    KW - Woody encroachment

    KW - Simulation modeling

    KW - Kwongan

    M3 - Master's Thesis

    ER -