[R-sig-eco] adonis with blocking (not nesting)

[Holland, Jeffrey D]

Dear R for ecology experts,
I have found many discussions online about blocking and nesting in adonis, but no answers for blocking.  I have community data with abundances within 42 aquatic genera (final.fd[,9:36]) from 2 types of streams (type).  Stream samples were paired (pair) as a blocking factor.  So the individual samples (n=12; I know, permuations will be limited) are one of two types and blocked within pairs.  I am using strata to restrict permuations within the blocking factor. However, I haven't found a way to specify the blocking in the data structure.
   If I use paired=T, how do I specify the pairing variable?  
adonis(final.fd[,9:42] ~ final.fd$type, paired=T, method = "bray", strata=final.fd$pair)
   If there is another way to set the blocking factor, what is it?
Much appreciated all,
Jeff

Jeffrey D. Holland, jdhollan at purdue.edu
Assoc. Prof., Dept. of Entomology
Purdue University