DESCRIPTION

r.li.pielou calculates the "Pielou's diversity index" as:
r.li.pielou formula
with:

NOTES

Do not use absolute path names for the config and output file/map parameters. If the "moving window" method was selected in r.li.setup, then the output will be a raster map, otherwise an ASCII file will be generated in the folder C:\Users\userxy\.r.li\output\ (MS-Windows) or $HOME/.r.li/output/ (GNU/Linux).

If the input raster contains NULL value cells, r.li.pielou returns -1 for these cells.
If you want to change these -1 values to NULL, run subsequently on the resulting map: 

r.null setnull=-1 map=my_map
after index calculation.

EXAMPLES

To calculate Pielou's diversity index on map my_map, using my_conf configuration file (previously defined with r.li.setup) and saving results in my_out, run: 
r.li.pielou map=my_map conf=my_conf output=my_out

Forest map (Spearfish sample dataset) example: 

g.region rast=landcover.30m -p
r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())"
r.li.pielou map=forests conf=movwindow7 out=forests_pielou_mov7
r.univar forests_pielou_mov7

Forest map (North Carolina sample dataset) example: 

g.region rast=landclass96 -p
r.mapcalc "forests = if(landclass96 == 5, 1, null() )"
r.li.pielou map=forests conf=movwindow7 out=forests_pielou_mov7

# verify
r.univar forests_pielou_mov7
r.to.vect input=forests output=forests feature=area
d.mon x0
d.rast forests_pielou_mov7
d.vect forests type=boundary

SEE ALSO

r.li - package overview
r.li.setup

REFERENCES

McGarigal, K., and B. J. Marks. 1995. FRAGSTATS: spatial pattern analysis program for quantifying landscape structure. USDA For. Serv. Gen. Tech. Rep. PNW-351. (PDF)

AUTHORS

Luca Delucchi and Duccio Rocchini, Fondazione E. Mach (Italy), based on the r.li.shannon code developed by Serena Pallecchi student of Computer Science University of Pisa (Italy).

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