competition_density: Competition density function

View source: R/growth_transition_functions-class.R

competition_densityR Documentation

Competition density function


Adjusts the life-stage transition matrix in each cell based on the carrying capacity in the cell and a density dependence function - default is Beverton-Holt. The user may specify which life-stages are affected by density dependence. If R_max is not provided this is calculated from the local cell-based transition matrices internally. By providing initial stable age distribution values, performance can be increased as the function internally calculates these values through optimisation.


  stages = NULL,
  mask = NULL,
  R_max = NULL,
  stable_age = NULL



which life-stages contribute to density dependence - default is all


a matrix of boolean values (TRUE/FALSE), equal in dimensions to the life-stage transition matrix and specifying which vital rates (i.e. survival and fecundity) are to be modified by the function


optional value of maximum growth rate (lambda) if known


optional vector of stable age distributions if known


# Vital rates (survival and fecundity) modified based on approach to carrying capacity
# by the 2nd and 3rd life stages.

## Not run: 
mod_fun <- competition_density(stages = c(2, 3))

ls <- landscape(population = egk_pop, suitability = NULL, carrying_capacity = egk_k)

pd <- population_dynamics(change = growth(egk_mat, transition_function = mod_fun))

simulation(landscape = ls, population_dynamics = pd, habitat_dynamics = NULL, timesteps = 20)

## End(Not run)

steps documentation built on Oct. 5, 2022, 1:06 a.m.