ChileanJAR

The native vegetation of "ñadi" soils in Valdivia province of Chile was studied. 32 vegetation samples were used applying the South-European phytosoeiological methods. An initial table including 167 speeies was made with these samples. In this table the frequency and coverage of the species were analyzed. tocalculate an importance value of each. Alter determining the heterogeneity of the initialtable, it was ordered in groups using di"erential species. Thls traditional ordination was compared with others obtained with the use of statistical multívariate classification and ordination methods. The primitive forest vegetation of the Valdivian ñadi soils Is formed by three syntaxa, two associations: Nothofago-Eueryphietum cordifoliae (coihué-ulmo forest) and Chusqueo-Nothofagetum entareticae (ñirre forest) and one subassociation, the Chusqueo-Nothofagetum entafeticee Bleehnetosum (canelo forest). The former occupies the most favourable biotops, while the ñirre forest oceupies, the least favourable ones. The canelo forest has an intermediate position but nearer to the ñirre foresto The dlstribution of species and communities wis determined first y by the temperature, second y by durations of wínter overfloods and in third place by the soll organic matter contento