El bosque mesófilo de la región de Puerto Soledad (Oaxaca), México: Análisis estructural

Spatial variation of a mesophyllous montane forest (=cloud forest, montane rain forest) tree community structure (dbh ≥ 3.18 cm; girth≥ 10 cm) was evaluated by sampling with the point-centered quadrat technique at six contrasting environments at Puerto Soledad, Oaxaca: East-facing slope, North-facing slope, West-facing slope, South-facing slope, Mountain Top and Wet Ravine. Density ranged between 505 and 2,730 ind ha•1, and basal area between 41.8 and 172 m2 ha•1. Forest structure at the Mountain Top greatly differed from that in other environments, as the smallest density and largest basal area were found there. Total canopy cover was > 150% in all environments. Canopy height ranged between 20 and 35 m; no well defined strata were found at any site. Structurally important species were: Arctosta.phylos mguta, Clethra. licanoides, C. mexicana, Cyathea fulva, Ilex discolor, Podocarpus reichei, Quercus acherdophylla, Q. eugenifolia, Q. rysophylla and Ternstroermia lineata. Diameter-based population structures for the most abundant species were very variable, but in general small diameter classes were the best represented. According to an association analysis, around 12% of the 34 examined species pairs showed significant, negative associations. In general, the structural values assessed for the studied mesophyllous montane forest fall within the range for similar forests in other regions; however, the results of this study clearly show the large heterogeneity of the vegetation within a single locality, although this variability is more noticeable for some variables (e.g. density, basal area) than for others (e.g. cover). This study supports the idea that under the mesophyllous montane forest (bosque mesófilo de montaña), a diverse array of plant communities is grouped.