Mantle communities of the temperate woodlands of South Central Chile: a phytosociological study of the order Aristotelietalia chilensis
Amigo, Javier; Ramírez, Carlos; Quintanilla, Luis G.
This study deals with the heliophilous shrub communities associated as prewoodland mantle communities with the wet temperate woodlands of South Central Chile. Previous studies have defined some communities proposed to belong to the order Aristotelietalia chilensis, subordinated to the principal class of the wet temperate woodlands of the Wintero-Nothofagetea; but a lack of data from large areas with potential woodlands in this class has been a significant impediment to effective interpretation of the vegetation series of the temperate regions of Chile. We have analyzed this type of vegetation in Chile between the 36th and 44th parallels, and have also considered some relevés from nearby areas of Argentina. We propose seven associations within the Aristotelietalia chilensis, divided into two alliances:a) The Berberidion buxifoliae groups those associations showing a certain mediterranean or xerophilous climatic influence, namely 1) Alstroemerio aurantiacae-Aristotelietum chilensis, the most northerly association with strongest mediterranean influence, 2) Rhaphithamno spinosi-Aristotelietum chilensis, the type community of the alliance, 3) Azaro microphyllae-Aristotelietum chilensis ass. nova, the most continental community of the alliance, and 4) Fuchsio magellanicae-Chusqueetum quilae, thermophilous and with distribution restricted to the coastal belt.b) The Fuchsio magellanicae-Amomyrtion lumae all. nova groups the associations of the typical ultra/hyperhumid Valdivian territory, namely 1) Aristotelio chilensis-Fuchsietum magellanicae, occurring in the lowest-altitude areas, 2) Lomatio ferrugineae-Amomyrtetum lumae ass. nova, more cold-tolerant than the preceding community, and 3) the supratemperate Escallonio alpinae-Fuchsietum magellanicae ass. nova, the most orophilous community occurring in the upper levels of the supratemperate woodlands.A number of subassociations and variants are proposed to reflect the variability observed within the different associations. We do not consider the alliance Gaultherion phillyreaefoliae to fall within this order, and we leave open the possible status of the alliance Escallonion rubrae, described from Argentinian territory, until more data become available. Each association is related to the woodland communities that it fringes, recognizing that in the syntaxonomy of Chilean woodlands there remain units to be described. Finally, we propose consideration of Aristotelienea chilensis as a subclass rather than an independent class.