mortality: Directly affect populations

In steps: Spatially- and Temporally-Explicit Population Simulator

Directly affect populations

Description

This function modifies a population by a mortality spatial layer included in a steps landscape object. The mortality layer consists of values from 0???1 and modifies the population by multiplying the population of a cell by the value of the corresponding cell in a mortality layer. For example, a cell with ten individuals before the mortality function is applied, and corresponding mortality layer cell with a value of 0.2, would have two individuals remaining after modification. Note, rounding also occurs after modification using a ceiling method (i.e the largest whole integer is retained).

Usage

mortality(mortality_layer, stages = NULL)

Arguments

mortality_layer	the name of spatial layer(s) in the landscape object with mortality proportions used to alter the populations for each timestep. If a stack of rasters is used then the number of layers must match the intended number of timesteps in the simulation.
stages	which life-stages are modified - default is all

Examples

# Modify populations in all life-stages with fire intensity.

## Not run: 
fire_mortal <- mortality(mortality_layer = "fire", stages = NULL)

ls <- landscape(population = egk_pop,
                suitability = egk_hab,
                carrying_capacity = egk_k,
                "fire" = egk_fire)

pd <- population_dynamics(change = growth(egk_mat), modification = fire_mortal)

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.