pielouEvenness: Calculates Pielou's Species Evenness

Description Usage Arguments Details Value Author(s) References See Also Examples

View source: R/pielouEvenness.R


This function calculates Pielou's Species Evenness for j areas and i years.


pielouEvenness(X, groups, species.table = NULL, metric = "ABUNDANCE",



A dataframe of fishery independent data derived from research vessel survey data or model output, with columns YEAR, ID, SPECIES, and ABUNDANCE. YEAR indicates the year the observation was recorded, ID is an area code indicating where the observation was recorded, SPECIES is a numeric code indicating the species sampled, and ABUNDANCE is the corresponding abundance (stratified and corrected for catchability as required).


A vector indicating the species group(s) for which to calculate the indicator. If groups = "ALL", all species will be included; otherwise, each entry must be a character string matching the name of a column in species.table.


A table where the column names match the entries in groups. Column entries are species codes indicating the species from X included in each group. species.table may also include columns for other species groups; these will be ignored. If groups = "ALL", this table is not required. Default is species.table = NULL.


A character string indicating which column in X to use to calculate the indicator. Default is metric = "ABUNDANCE".


A vector of years for which to calculate indicator.


Pielou's Species Evenness:

J' = -Σ p_i ln( p_i )/ln(S)

p_i is the proportion of the total sample contributed by the i(th) species and S is the number of species recorded in the sample. Pielou's Index is the Shannon-Weiner Index computed for the sample S and represents a measure of evenness of the community (Pielou, 1966).


Returns a dataframe with columns ID and YEAR, and a column PielouEvenness_group for each entry in groups.

If there is no data for spatial scale j in year i, indicator values is assigned NA.


Danielle Dempsey Danielle.Dempsey@dfo-mpo.gc.ca, Adam Cook, Catalina Gomez, Alida Bundy


Bundy A, Gomez C, Cook AM. 2017. Guidance framework for the selection and evaluation of ecological indicators. Can. Tech. Rep. Fish. Aquat. Sci. 3232: xii + 212 p.

Greenstreet SP, Rogers SI. 2006. Indicators of the health of the North Sea fish community: identifying reference levels for an ecosystem approach to management. ICES J Mar Sci J du Cons 63:573 593

Pielou EC. 1975. Ecological Diversity. Wiley, New York. ISBN 0-471-68925-4

See Also

Other biodiversity indicators: allBiodiversity, heips, hillN1, hillN2, kemptonQ, margalef, shannon, speciesRichness


pielouEvenness(X, groups = "ALL", species.table = NULL, metric = "ABUNDANCE", 
   years = c(2014:2019))

Example output

      ID YEAR PielouEvenness_ALL
1  AREA1 2014          0.3641888
2  AREA1 2015          0.3894733
3  AREA1 2016          0.3281575
4  AREA1 2017          0.4007546
5  AREA1 2018          0.4218297
6  AREA1 2019          0.2703277
7  AREA2 2014          0.3972961
8  AREA2 2015          0.4252770
9  AREA2 2016          0.3828098
10 AREA2 2017          0.4034722
11 AREA2 2018          0.3196600
12 AREA2 2019          0.3631935

marindicators documentation built on Nov. 12, 2019, 5:07 p.m.