A graph is produced that summarizes (through GAM as implemented by gam) how the abundance of all species of the community data set change along an ordination axis (based on the position of sites along the axis and the information from the community data set).
Usage
ordicoeno(x,ordiplot,axis=1,...)
Arguments
x
Community data frame with sites as rows, species as columns and species abundance as cell values.
Axis of the ordination graph (1: horizontal, 2: vertical).
...
Other arguments passed to functions plot and points.
Value
The function plots coenoclines and provides the expected degrees of freedom (complexity of the relationship) estimated for each species by GAM.
Details
This functions investigates the relationship between the species vectors and the position of sites on an ordination axis. A GAM (gam) investigates the relationship by using the species abundances of each species as response variable, and the site position as the explanatory variable. The graph shows how the abundance of each species changes over the gradient of the ordination axis.
References
Kindt, R. & Coe, R. (2005)
Tree diversity analysis: A manual and
software for common statistical methods for ecological and
biodiversity studies.
http://www.worldagroforestry.org/resources/databases/tree-diversity-analysis