This script is designed to transform Braun-Blanquet abundance information into relative abundances or average recovery values (between 0 and 100).

PRE_FATE.abundBraunBlanquet(abund)

Arguments

abund

a vector with abundance values from Braun-Blanquet (+, r, 1, 2, 3, 4, 5), and with NA when no information

Value

A vector with numerical values between 0 and 100 corresponding to the median of each recovery class.

Details

Braun-Blanquet values allow to estimate the abundance-dominance of a species based on an estimation of the number of individuals and the covering surface. A correspondence has been defined between this index and average recovery values :

| Braun-Blanquet | Recovery class (%) | Average recovery (%) |
____________________________________________________________
| + ............ | ............... <1 | ................ 0.5 |
| 1 ............ | .............. 1-5 | .................. 3 |
| 2 ............ | ............. 5-25 | ................. 15 |
| 3 ............ | ............ 25-50 | ............... 37.5 |
| 4 ............ | ............ 50-75 | ............... 62.5 |
| 5 ............ | ........... 75-100 | ............... 87.5 |
##' ____________________________________________________________
| 0 ............ | .................. | .................. 0 |
| NA ........... | .................. | ................. NA |



Braun-Blanquet J., Roussine N. & Nègre R., 1952. Les groupements végétaux de la France méditerranéenne. Dir. Carte Group. Vég. Afr. Nord , CNRS, 292 p.

Baudière A. & Serve L., 1975. Les groupements végétaux du Plade Gorra-Blanc (massif du Puigmal, Pyrénées Orientales). Essai d'interprétation phytosociologique et phytogéographique. Nat. Monsp., sér. Bot., 25, 5-21.

Foucault B. (de), 1980. Les prairies du bocage virois (Basse-Normandie, France). Typologie phytosociologique et essai de reconstitution des séries évolutives herbagères. Doc. Phytosoc., N.S., 5, 1-109.

Author

Maya Guéguen

Examples


abund_BB = sample(x = c(NA, "+", "r", 1:5), size = 100, replace = TRUE)
abund = PRE_FATE.abundBraunBlanquet(abund_BB)
summary(abund)