# density_dependence_dispersing: Density-dependent proportions of populations dispersing In steps: Spatially- and Temporally-Explicit Population Simulator

 density_dependence_dispersing R Documentation

## Density-dependent proportions of populations dispersing

### Description

The proportion of populations dispersing will be density dependent in a simulation. Proportions of populations in each life stage dispersing is adjusted based on available carrying capacity. If life-stages are set by the population_density_dependence_functions, these will be used to determine how close the population is to carrying capacity. If no life-stages are set or density dependence is set to NULL in population_dynamics, the function will consider all life-stages in the calculation.

### Usage

```density_dependence_dispersing(maximum_proportions = 1)
```

### Arguments

 `maximum_proportions` A single value or vector of the maximum proportions (between zero and one) of individuals in each life stage that disperse - default is 1. If maximum proportions are specified as a single number, then all life-stages use that value, however, a vector of maximum proportions (equal in length to the number of life-stages) can also be specified. Maximum proportions are multiplied by the calculated proportions based on carrying capacity so to prevent stages from dispersing, set corresponding values to zero.

### Value

An object of class `dispersal_proportion_function`

### Examples

```
# Example of a proportion function that disperses all populations based on their approach
# to carrying capacity

## Not run:
prop_dispersal <- density_dependence_dispersing()

kb_dispersal <- kernel_dispersal(dispersal_proportion = prop_dispersal,
max_distance = 2000,
dispersal_kernel = exponential_dispersal_kernel(distance_decay = 1000))

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

pd <- population_dynamics(change = growth(egk_mat), dispersal = kb_dispersal)

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.