Functions to estimate fire effects on foliage, buds and cambium, based on the model by Michaletz & Johnson (2008)
Usage
fire_plumeTemperature(Ib_surf, z, T_air = 25, rho_air = 1.169)
fire_barkThermalDiffusivity(fmc_bark, rho_bark = 500, T_air = 25)
fire_radialBoleNecrosis(
Ib_surf,
t_res,
bark_diffusivity,
T_air = 25,
rho_air = 1.169,
T_necrosis = 60
)
fire_leafThermalFactor(SLA, h = 130, c = 2500)
fire_necrosisCriticalTemperature(
t_res,
thermal_factor,
T_air = 25,
T_necrosis = 60
)
fire_necrosisHeight(
Ib_surf,
t_res,
thermal_factor,
T_air = 25,
rho_air = 1.169,
T_necrosis = 60
)
Arguments
- Ib_surf
Surface fireline intensity (kW/m).
- z
height (m).
- T_air
Air temperature (degrees Celsius).
- rho_air
Air density (kg/m3).
- fmc_bark
Bark moisture content (% dry weight).
- rho_bark
Bark density (kg/m3).
- t_res
fire residence time (seconds).
- bark_diffusivity
Bark thermal diffusivity (m2/s).
- T_necrosis
Temperature of tissue necrosis (degrees Celsius).
- SLA
Specific leaf area (m2/kg).
- h
Heat transfer coefficient
- c
Specific heat capacity
- thermal_factor
Tissue thermal factor.
Value
Function
fire_plumeTemperature
returns the plume temperature at a given height.Function
fire_barkThermalDiffusivity
returns the bark thermal diffusivity given a bark moisture value.Function
fire_radialBoleNecrosis
returns the depth of radial bole necrosis in cm.Function
fire_leafThermalFactor
returns the thermal factor of leaves as a function of specific leaf area.Function
fire_necrosisCriticalTemperature
returns the (plume) temperature yielding necrosis for a given residence time and tissue thermal factor.Function
fire_necrosisHeight
returns the height (in m) of necrosis for tissues with given thermal factor.
References
Michaletz, S.T., and Johnson, E.A. 2006. A heat transfer model of crown scorch in forest fires. Can. J. For. Res. 36: 2839–2851. doi:10.1139/X06-158.
Michaletz ST, Johnson EA. 2008. A biophysical process model of tree mortality in surface fires. Canadian Journal of Forest Research 38: 2013–2029.