iti {benthos}R Documentation

Infaunal Trophic Index (ITI)

Description

Computes the Infaunal Trophic Index (ITI) according to Gittenberger & van Loon (2013).

Usage

iti(.data = NULL, taxon, count, group = NULL)

iti_(.data = NULL, taxon, count, group = NULL)

has_iti(.data = NULL, taxon, group = NULL)

has_iti_(.data = NULL, taxon, group = NULL)

Arguments

.data

data in a data.frame, data_frame, data.table, database etc.

taxon

species names

count

counts of individuals (numeric)

group

sensitivity groups I, II, III, or IV

Details

The Infaunal Trophic Index (ITI) is given by

\mathrm{ITI} = 100 ∑_{i=1}^3 \frac{(4-i)}{3} p_i

where p_i is the proportion of species in class i, where

Value

numeric vector of length 1 containing the ITI

Functions

References

Gittenberger A. and W. van Loon, 2013. Sensitivities of marine macrozoobenthos to environmental pressures in the Netherlands. Nederlandse Faunistische Mededelingen 41: 79-112.

Examples

     iti(taxon = c("Euspira pulchella", "Nephtys cirrosa"), count = c(4, 6))
     
 
   data(oosterschelde)
   has_iti(oosterschelde, TAXON)
 

[Package benthos version 1.3-6 Index]