gridUncertainty {redlistr}

Function to compute AOO with grid uncertainty systematically with stopping rule

Description

gridUncertainty determines the number of area of occupancy (AOO) grid cells occupied by a species or ecosystem systematically. It will only stop when the AOO calculated does not improve (decrease) after a set number of split scenarios.

Usage

gridUncertainty(
  input.data,
  grid.size,
  n.AOO.improvement,
  min.percent.rule = FALSE,
  percent = 1
)

Arguments

input.data

Spatial object of an ecosystem or species distribution. Please use a CRS with units measured in metres.

grid.size

A number specifying the width of the desired grid square (in same units as your coordinate reference system)

n.AOO.improvement

Specifies the minimum number of rounds the calculated AOO is not improved before stopping the function.

min.percent.rule

Logical. If TRUE, a minimum area threshold must be passed before a grid is counted as an AOO grid.

percent

Numeric. The minimum percent to be applied as a threshold for the min.percent.rule.

Value

A list containing the following:

• Data frame of results showing the minimum AOO calculated for each shift scenario

• Single SpatialPolygonsDataFrame containing the AOO grid which would produce the minimum AOO calculated

Author(s)

Calvin Lee [e-mail]

See Also

Other gridUncertainty functions: gridUncertaintyBase(), gridUncertaintyRandomManual(), gridUncertaintyRandom(), gridUncertaintyRestricted(), gridUncertaintySimulation()

Examples

crs.UTM55S <- '+proj=utm +zone=55 +south +ellps=WGS84 +datum=WGS84 +units=m +no_defs'
r1 <- raster(ifelse((volcano<130), NA, 1), crs = crs.UTM55S)
extent(r1) <- extent(0, 6100, 0, 8700)
x <- gridUncertainty(r1, grid.size = 1000, n.AOO.improvement = 5,
                           min.percent.rule = FALSE, percent = 1)