model.lange.apply: Use the Lange model

In barrks: Calculate Bark Beetle Phenology Using Different Models

Use the Lange model

Description

This page describes the usage of the the Lange model with phenology(). The model specific inputs are listed and its basic functionality is explained. The model was published by \insertCiteLange2008;textualbarrks for Ips typographus.

Arguments

tmin, tmean, tmax	Daily minimum/mean/maximum temperatures in °C.
.submodels, .onset, .diapause, .mortality, ...	See phenology() for a detailled description of the function.

Details

In barrks, phenology() is used to apply a model. The following code illustrates which inputs are required to apply the Lange model and which additional parameters are available.

phenology("lange", ..., tmin, tmean, tmax)

# calculate submodels separately
phenology("lange", ..., .submodels = 'onset', tmean, tmax)
phenology("lange", ..., .submodels = 'mortality', tmin)
phenology("lange", ..., .submodels = 'development',
          .onset, .diapause = NULL, .mortality = NULL,
          tmean, tmax)

Value

The function returns a phenology. Look here to find out how it can be analysed.

Functioning

In the following, the basic functioning of the Lange model is explained.

• Onset: The onset of swarming is triggerd when the degree days of the maximum temperature reach a specific threshold and the maximum temperature exceeds the minimum flight temperature according to \insertCiteAnnila1969;textualbarrks.

• Development: The development is calculated using stage-specific temperature sums and thresholds \insertCiteWermelinger1998barrks. A new generation starts its development when the last generation finished its development and the maximum temperature exceeds the minimum flight temperature.

• Diapause: The Lange model does not have a diapause submodel implemented.

• Mortality: White stages (egg to pupa) die when the minimum temperature falls below a specific threshold.

Look here to find out how the model parameters affect the actual calculations and which values are used by default.

References

\insertAllCited

See Also

model(), phenology(), model.lange.customize

Other phenology applications: model.bso.apply, model.chapy.apply, model.joensson.apply, model.phenips.apply, model.phenips_clim.apply, model.rity.apply

barrks documentation built on Aug. 29, 2025, 5:32 p.m.