# protectedAreaSelection: Function to select optimal network of protected areas based... In ConnMatTools: Tools for Working with Connectivity Data

## Description

This function finds the optimal network of protected areas based on connectivity using the eigenvalue perturbation approach described in Nilsson Jacobi & Jonsson (2011).

## Usage

 ```1 2 3``` ```protectedAreaSelection(conn.mat, nev = dim(conn.mat)[1], delta = 0.1, theta = 0.05, M = 20, epsilon.lambda = 1e-04, epsilon.uv = 0.05, only.list = T, ...) ```

## Arguments

 `conn.mat` a square connectivity matrix. `nev` number of eigenvalues and associated eigenvectors to be calculated. `delta` the effect of protecting site i (e.g. increase in survival or fecundity in protected areas relative to unprotected areas). Now a single value, in future it will be possible to specify site-specific values. The perturbation theory used in the construction of the algorithm assumes delta to be small (e.g. delta=0.1). However, higher values give also good results. `theta` the threshold of donor times recipient value that a site must have to be selected. `M` the maximal number of sites selected from each subpopulation even if there are more sites above the threshold theta `epsilon.lambda` Threshold for removing complex eigenvalues. `epsilon.uv` Threshold for removing eigenvectors with elements of opposite signs of comparable magnitude. `only.list` Logical, whether the function return only the list of selected sites or also the predicted impact of each selected site on the eigenvalues `...` Additional arguments for the `eigs` function.

## Value

If only.list is `TRUE`, just returns the list of selected sites. If `FALSE`, then result will be a list containing selected sites and predicted impact of each selected site on the eigenvalues.

## Author(s)

Marco Andrello [email protected]

## References

Jacobi, M. N., and Jonsson, P. R. 2011. Optimal networks of nature reserves can be found through eigenvalue perturbation theory of the connectivity matrix. Ecological Applications, 21: 1861-1870.

ConnMatTools documentation built on May 30, 2017, 5:35 a.m.