I don't think anybody doubts the complexity of specific relationships
between fire and ecosystems, especially when you're talking about narrow
specific ecosystems such as that paper. As I said too much and not enough
fire are both problems. Last time I checked, South West WA does not make
up the "vast majority" of Australia, and "vast majority" does not mean all.
Jeremy
On 5 September 2013 15:57, Stephen Ambrose <> wrote:
> > The vast majority of Australia's bush is adapted to regular fire regimes
> -
> especially Eucalyptus forests, inland mallee and grassland.
>
>
> The following review paper written by eminent biologists from the
> University
> of WA and Kings Park & Botanic Garden in Perth provides the contrary view
> for native vegetation that occurs in south-western and south-eastern
> Australia:
>
> Bradshaw, SD, Dixon, KW, Hopper, SD, Lambers, H., & Turner, SR (2011).
> Little evidence for fire-adapted plant trails in Mediterranean climate
> regions. Trends in Plant Science 16: 69-76
>
> The paper was written out of the authors' concerns of the ecological
> impacts
> of the extensive control-burning that occurs in south-western Australia,
> similar to those concerns already expressed by Frank O'Connor here on
> Birding-aus.
>
> Abstract
>
> As climate change increases vegetation combustibility,
> humans are impacted by wildfires through loss of lives
> and property, leading to an increased emphasis on prescribed
> burning practices to reduce hazards. A key and
> pervading concept accepted by most environmental
> managers is that combustible ecosystems have traditionally
> burnt because plants are fire adapted. In this
> opinion article, we explore the concept of plant traits
> adapted to fire in Mediterranean climates. In the light of
> major threats to biodiversity conservation, we recommend
> caution in deliberately increasing fire frequencies
> if ecosystem degradation and plant extinctions are to be
> averted as a result of the practice.
>
> The Paper's Conclusion
>
> Our review of the literature suggests that traits commonly
> accepted as 'fire adaptations' of Mediterranean-climate
> plants have more complex origins and that environmental
> factors other than frequent fire have promoted their evolution
> [97]. Traits such as resprouting, serotiny, physical
> dormancy, facultative post-fire flowering and smoke-induced
> germination can all enhance survivorship and fitness
> under certain fire regimes, but these should be considered as
> exaptations rather than adaptations (Table 1). This selective
> advantage is readily negated, however, in plant communities
> in which fires occur with a frequency higher than
> the time taken to flower and set seed for the slowest-maturing
> species in that community. The impact of fires on
> communities is also a function of their intensity and the
> season in which they occur, both of which can override any
> inherent advantages flowing from morphological and physiological
> exaptations. Climate change, with increasing temperatures
> and declining rainfall predicted in Mediterranean
> biomes in the coming decades, is likely to exacerbate the
> current loss of biodiversity in these regions and will present
> a major challenge for environmental managers also charged
> with protecting human life and property [98]. We question
> the widespread assumption that Mediterranean-ecosystem species
> are adapted to fire and suggest that caution is
> required in the use of frequent prescribed burning if ecosystem
> degradation and plant extinctions are to be averted as a
> result of the practice.
>
> Kind regards,
> Stephen
>
> Dr Stephen Ambrose
> Ryde NSW
>
>
>
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