This page describes the parameters that can be used to customize CHAPY. The model was developed by Ogris2020;textualbarrks. Look here to find out how to apply the model.
The date, when the degree days start to sum up ('MM-DD').
Base temperature to calculate degree days to trigger the onset.
Degree days that are required to trigger the onset of
infestation. Additionally, the maximum temperature must exceed tfly.
Minimum temperature that beetles need to fly.
Base temperature to calculate degree days for development.
Degree days that are required for a generation to fully develop
Share in total development when the egg development starts and the juvenile beetle's development ends respectively. Usable if the development below/above these thresholds should account for mating, oviposition etc.
Share in the total development, when a sister brood will be established.
The beetles are considered to be in
white stages (egg, larva, pupa) if their development exceeds dev_mortal_min
and subceeds dev_mortal_max. During these stages, the beetles could die
due to a mortality event. NULL means that no lower/upper threshold is
defined.
Functions to caclulate the air temperature in forest stands (see Ogris2019;nobracketsbarrks, equations 1 - 3). Each parameter will be passed as SpatRaster:
tmin: min air temperature
tmean: mean air temperature
tmax: maximum air temperature
Functions to caclulate the bark temperature (see Ogris2019;nobracketsbarrks, equations 4 - 6). Each parameter will be passed as SpatRaster:
ftmin: min air temperature in forest stands
ftmean: mean air temperature in forest stands
ftmax: maximum air temperature in forest stands
Parameters to calculate the effective bark temperature (see Ogris2020;nobracketsbarrks, equations A.7 - A.9).
Date when the model ends (no further development will be modeled).
When the daylength falls below this threshold, diapause will be initiated.
Date when all white stages (egg, larva, pupa) die.
In barrks, model() is used to customize a model. The following code
illustrates which parameters are available for CHAPY and specifies their
default values.
model("chapy", # ==== onset ====
dd_onset_start_date = '03-09',
dd_onset_base = 7.4,
dd_onset_threshold = 216.5,
# ==== onset + development ====
tfly = 15.6,
# ==== development ====
dd_development_base = 7.4,
dd_total_dev = 635.4,
dev_start = 0,
dev_end = 1,
dev_sister_brood = 0.5,
dev_mortal_min = NULL,
dev_mortal_max = 0.8,
func_ftmin = function(tmin) { 1.44 + 0.82 * tmin },
func_ftmean = function(tmean) { 0.50 + 0.81 * tmean },
func_ftmax = function(tmax) { 1.03 + 0.86 * tmax },
func_btmin = function(atmin) { 0.56 + 0.99 * atmin },
func_btmean = function(atmean) { -0.48 + 1.03 * atmean },
func_btmax = function(atmax) { 0.03 + 0.99 * atmax },
dt_low = 7.4,
dt_up = 39.4,
topt = 30,
tmax = 41.97,
alpha = 0.031,
beta = 5.3,
gamma = 1.25,
model_end_date = '12-31',
# ==== diapause ====
daylength_dia = 13.6,
# ==== mortality ====
mortality_date = '12-31'
)
model(), phenology(), model.chapy.apply
Other model customizations:
model.bso.customize,
model.joensson.customize,
model.lange.customize,
model.phenips.customize,
model.phenips_clim.customize,
model.rity.customize