Bachelor of Conservation Biology (Honours)
School of Earth, Atmospheric and Life Sciences
Morrison-Jones, Milo, Why the insensitivity? Plant species across New South Wales tolerating short fire intervals, Bachelor of Conservation Biology (Honours), School of Earth, Atmospheric and Life Sciences, University of Wollongong, 2021.
Fire as a global disturbance has acted across millions of years to shape terrestrial biomes. It has shaped the evolution of plants in concert with other disturbances and shape flora as we know it today. Increased global fire activity has posed the question to managers of how best to manipulate fire regimes to benefit people and biodiversity. Cultural burning is a form of prescribed burning undertaken by Indigenous people for a variety of reasons (often frequently at low intensities) promoting the regenerative aspects of fire. The frequency at which this is applied can be at odds with fire interval-based ‘thresholds’ developed by scientists, such as those generated based on plant life history traits for New South Wales (NSW), Australia. Using combinations of critical plant traits (plant functional types), predictions about future vegetation change are made possible.This study sought to explore whether the shortest fire intervals (minimum intervals) experienced in past observations of fire sensitive plant species affected their survival. Five prevalent fire-prone vegetation formations were chosen in which to test minimum intervals against the primary juvenile periods of fire sensitive (obligate seeding) species. Other factors (role of sample size, fire type and systematic differences in plant functional types) were also explored. The overall results are very strong in suggesting that minimum intervals in the past do not affect the subsequent survival of fire sensitive plant species in NSW. This is unexpected when considering their life history traits and the information given in the NSW Flora Fire Response Database. The most likely explanation is the fire patchiness within fire perimeters enabling adult plants to survive. Other likely explanations include variation in life history traits (such as resprouting response and juvenile period) and seedbank longevity. The insensitivity of these ‘vulnerable’ plants to landscape scale fire intervals as used in NSW fire management is called into question, and it is likely that concerns about the effects of high fire frequency on flora are overestimated to some degree. The increasing calls for Cultural burning to light landscapes again may not have as detrimental effect on plant populations if they are patchy. Managers are implored
FoR codes (2008)
060208 Terrestrial Ecology
Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.