ANÁLISIS DE LA DISTRIBUCIÓN DE LAS ESPECIES DE HELECHOS Y AFINES DEL VALLE DE MÉXICO, NOTAS ECOLÓGICAS Y FLORÍSTICAS*

Abstract

An analysis of distribution for 40 genera
and 113 species of pteridophytes from the
Valley of Mexico according vegetation’s
types of Rzedowski (2001) is presented. We
found 54% of the species in cloud forest;
45% in conifers forests; 33.6% in Quercus
forest; 34.5% in grasslands; 28% in xerophilous scrubs; 22% in pine-oak forest;
3.5% in Quercus scrub and 1.8% in aquatic
vegetation as in halophyllous vegetation.
The affinities between the pteridophytes
of the different communities were analyzed using presence/absence data with the
Sörensen’s similarity index and UPGMA
method to construct the dendrogram, and
we found more similarity between Pinus
forest and the Abies forest. Quercus forest
is related to the cloud forest, and the xerophilous scrubs is similar with glassland.
The hallophyllous vegetation has little
relation with another communities and
the aquatic vegetation has not relation with
any other.