loadTreatment {landsepi} | R Documentation |
Load treatment parameters
Description
Loads a list of treatment parameters for a specific disease (initialised at 0 , i.e. absence of treatments)
Usage
loadTreatment(disease = "no pathogen")
Arguments
disease |
a disease name, among "mildew", "sigatoka" and "no pathogen" |
Details
Chemical treatment is applied in a polygon only if disease severity (i.e. I/N) in
this polygon exceeds the threshold given by treatment_application_threshold
.
Treatment efficiency is maximum (i.e. equal to the parameter treatment_efficiency)
at the time of treatment application (noted ); then it decreases with time
(i.e. natural pesticide degradation) and host growth (i.e. new biomass is not protected
by treatments): protected by treatments):Efficiency of the treatment at time t after the application date is given by:
with
:
is the reduction of fungicide concentration due to time (e.g. natural degradation, volatilization, weathering), with
the timelag passed since the time of treatment application.
-
is the reduction of fungicide concentration due to plant growth, since new plant tissue is not covered by fungicide.
and
being the number of host individuals a the time of treatment
and at time
, respectively.
-
and
are shape parameters.
Value
a list of treatment parameters:
treatment_degradation_rate = degradation rate (per time step) of chemical concentration,
treatment_efficiency = maximal efficiency of chemical treatments (i.e. fractional reduction of pathogen infection rate at the time of application),
treatment_timesteps = vector of time steps corresponding to treatment application dates,
treatment_cultivars = vector of indices of the cultivars that receive treatments,
treatment_cost = cost of a single treatment application (monetary units/ha)
treatment_application_threshold = vector of thresholds (i.e. disease severity, one for each treated cultivar) above which the treatment is applied in a polygon.
See Also
Examples
treat <- loadTreatment("sigatoka")
treat