Temporihygrophilous Quercus broteroi forests in southern Portugal: Analysis and conservation

Abstract

This article deals with a phytosociological survey of marcescent Portuguese oak (Quercus broteroi) forests in southern Portugal, and presents the results of an analysis of 56 relevés, combining Braun–Blanquet's methodology with hierarchical cluster analysis (Ward's Hierarchical Clustering, based on Bray–Curtis distance). From these results, a new temporihygrophilous Portuguese oak forest association is described. Largely thermomediterranean, upper dry to subhumid, Ulici welwitschiani–Quercetum broteroi occurs on limestone soils within the Coastal Lusitan-Andalusian Province. Its high conservation value – mainly due to its rarity and floristic structure – supports this forest's integration in Habitat 9240 (Annex B-I from Council Directive 92/43/EEC) in order to ensure its preservation. Based on the results, new biogeographic borders for the Ribatagan-Sadensean Sector are proposed.

Keywords:

• Biodiversity conservation
• hierarchical cluster analysis
• phytosociology
• Quercus broteroiwoodlands
• Vale do Guizo formation

Acknowledgements

The authors wish to thank the POCTEP OTALEX II Project for providing field trips which improved the authors' knowledge of the main subject of this article.