SIcalc: Calculate Suitability Indices

In MVR-GIS/nybem: NY Bight Ecological Model

Calculate Suitability Indices

Description

SIcalc computes suitability indices given a set of suitability curves and project-specific inputs. Suitability indices may be computed based on either linear interpolation (for continuous variables) or a lookup method (for categorical variables).

Usage

SIcalc(SI, input_proj)

Arguments

SI	data frame or matrix; matrix of suitability curves ordered as parameter breakpoints and associated suitability indices for each parameter.
input_proj	list; A list of numeric or categorical vectors of application-specific input parameters associated with the suitability curve data from SI.

Details

The SI parameter must contain a set of column pairs. The column pairs should consist of a

Value

A vector of the suitability index values that match given user inputs. Values are returned as equal to the extreme of a range if inputs are outside of model range.

References

• US Fish and Wildlife Service. (1980). Habitat as a basis for environmental assessment. Ecological Services Manual, 101.

• US Fish and Wildlife Service. (1980). Habitat Evaluation Procedures (HEP). Ecological Services Manual, 102.

• US Fish and Wildlife Service. (1981). Standards for the Development of Habitat Suitability Index Models. Ecological Services Manual, 103.

Examples

# Build manual model
# Number of trees > 51cm diameter per 0.4 ha plot
tree.num     <- c(0, 2, 4, NA)              # parameter breakpoints
tree.num.SIV <- c(0.1, 1, 1, NA)            # parameter suitability indices
tree_num <- data.frame(tree.num, tree.num.SIV)

# Mean diameter of overstory trees
avg.dbh      <- c(0, 5, 20, NA)             # parameter breakpoints
avg.dbh.SIV  <- c(0, 0, 1, NA)              # parameter suitability indices
tree_diameter <- data.frame(avg.dbh, avg.dbh.SIV)

# Percent canopy cover of overstory trees
can.cov      <- c(0, 20, 60, 100)           # parameter breakpoints
can.cov.SIV  <- c(0, 0, 1, 1)               # parameter suitability indices
canopy_cov <- data.frame(can.cov, can.cov.SIV)

barredowl <- data.frame(tree_num, tree_diameter, canopy_cov)

bo_test1 <- list(2, 5, 20)

# Barredowl si values
bo_si_1 <- nybem::SIcalc(barredowl, bo_test1)

MVR-GIS/nybem documentation built on Feb. 9, 2023, 7:03 a.m.