Three Parks Savanna Fire-effects Plot Network: Plot-based Fire Severity and Biomass Monitoring, Kakadu National Park, Northern Territory, Australia 

This data package comprises fire severity scores from Kakadu in 2014. A total of 220 permanent monitoring plots (40 m x  20 m) were established across three parks (Kakadu, Litchfield and Nitmiluk) in 1994-1995 to monitor biotic change. Of these, 132 plots are located in Kakadu. These sample a variety of landform and vegetation type/habitat conditions. A substantial proportion of plots were positioned deliberately at sites likely to reveal environmental dynamics, especially at ecotones and in patches of fire-sensitive vegetation. For example stands of Callitris, sandstone heaths. As well, many plots are located at, or in the near vicinity of, intensively managed sites such as camp-grounds and other tourist destinations. A synopsis of related data packages which have been collected as part of the Three Park Savanna Fire-effects Plot Network’s full program is provided at LTERN 

We at TERN acknowledge the Traditional Owners and Custodians throughout Australia, New Zealand and all nations. We honour their profound connections to land, water, biodiversity and culture and pay our respects to their Elders past, present and emerging. The authors acknowledge the contributions of park staff and traditional owners from Kakadu and Nitmiluk National Parks in laying the foundations of the work described here, and the singular importance of long-term funding support provided through Parks Australia (for Kakadu) and the Northern Territory’s Parks and Wildlife Service (for Nitmiluk).

The work was also supported by the Indigenous Land and Sea Corporation, the Nature Conservancy, Meat and Livestock Australia, ConocoPhillips Limited, and the North Australian Indigenous Land and Sea Management Alliance Limited. We acknowledge the financial support of Parks Australia (for the Kakadu vegetation plots) and the Northern Territory Parks and Wildlife Service (for the Litchfield and Nitmiluk plots) to carry out the vegetation monitoring. The Three Parks program is part of the Long Term Ecological Research Network, a facility of Australia's Terrestrial Ecological Research Network. 

Assess vegetation structure and fire effects on trees. 

• Plot set-up
  • The over-all plot sizes are 40 x 20 m. Each plot is permanently located by a central metal star picket and GPS waypoint. Plots relocated by helicopter have a round large white lid on top to assist sighting the plot from air.
  • A permanent photo picket with number plate is placed 10 m inside the plot parallel with the plot sides.
  • The corners and inner transects are marked by metal droppers.
  • The inner 40 x 10 m plot is delineated with measuring tapes. Two 50 m tapes are laid out 5 m either side of central photo picket, parallel to the longer central axis, starting at zero on the left hand side heading to the back of the plot, and again at zero on the right hand side heading to the top of the plot.
  • NB: some plots are not strictly 40 m due to plot landscape constraints.
  • Instruments: Metal star pickets, GPS, 50 m measuring tapes
• Record of fire occurrence
  • Fire occurrence is recorded based on on-ground plot visits, and from aerial ground-truthing assessments of each park’s satellite-based fire mapping programme.
  • An assessment is made as to whether the plot was unburnt, patchily burnt (ground cover at least 20% unburnt), or burnt, in three seasonal periods as follows: Wet season (w) - from onset of rains (typically November) until their cessation (typically March - April); Early dry season (e) - from end of wet season until end of July; Late dry season (L) - from August until start of rains.
  • Ground-based photos; Photos are supposed to be taken biannually, post wet season and late dry season. Often parks staff only manage one photo per year.
  • These images are not stored as part of this data package due to their size, but can be provided on request from Dr Russell-Smith or LTERN.
• Fire severity score
  • Fire severity is scored for each recorded fire event from plot photos.
  • Plot photos are scored by a member of the research team and fire managers from the park.
  • Two seasonal photos per plot in any 1 year are not always available. However, in nearly all instances it is possible to confidently attribute fires to (1) season, given recourse to comprehensive plot records; and (2) severity class, by close examination of differences between foliage condition and vegetation structure in photo temporal sequences.
  • Note: This method may not detect all fires of very low severity or high patchiness occurring especially in wet or early dry season periods given rapid post-fire regrowth under high soil moisture conditions.
  • Fire severity is recorded using one or more the following categories:
    • 1 = Low
    • 2 = Moderate
    • 3 = High
    • P = Patchily burnt
    • U = Unburnt
    • B = Burnt. Photo records missing
    • wet = Burn that occurred in the wet season
    • If no assessment is done the fire severity is recorded as NA.
• Plot photos are taken over the plot so the sampling area is equal to the area of the plot, 40 x 40 m. The frequency is twice per year, early dry season and late dry season.
• Sampling Description: The plot photo is taken from the middle picket along the the front edge of the plot, facing the a permanent photo point picket 10 m inside the plot.
• Biomass calculations: Biomass was calculated using allometric equations from Williams et al (2005). The biomass of dead stems was calculated using a reduction factor of 855 outlined in Bennett et al (2013) .