R help - Jun 2004 - chronological clustering

Does anybody know of any R functions to perform chronological clustering 
as explained in:

Legendre, P., S. Dallot & L. Legendre. 1985. Succession of species 
within a community: chronological clustering, with applications to 
marine and freshwater zooplankton. American Naturalist 125: 257-288.

http://www.fas.umontreal.ca/BIOL/legendre/reprints/succession_of_species.pdf

Thanks,
Angel