Dinâmica serial e contactos catenais das comunidades herbáceas anuais e vivazes do interior de Portugal continental (Beira Interior e Alentejo)

Abstract

This study present a phytosociological classification based on relevés conducted, according to the phytosociological methodology in perennial and annual herbaceous communities in Lusitan-Extremadurean, Carpetanian-Leonese and Atlantic Orolusitanian subprovinces, covering the centre-east and southeast of mainland Portugal. The main objective of this work is the characterisation of herbaceous communities, from the point of view of their floristic composition and variability, ecology, distribution and abundance in the studied area, syntaxonomy, catenal contacts, syndynamic and conservation status, based on data collected in the field or obtained from the literature. Nine classes of herbaceous vegetation have been identified, as well as three classes of shrubby vegetation, three classes of arboreous vegetation and a total of 65 associations. The surveyed communities are distributed by the classes: Isoeto-Nanojuncetea; Magnocarici elatae-Phragmitetea australis; Stellarietea mediae; Tuberarietea guttatae; Poetea bulbosae; Festuco-Brometea; Lygeo-Stipetea; Stipo giganteae-Agrostietea castellanae and Molinio-Arrhenatheretea. In the set of annual and perennial communities we identified 14 orders, 20 alliances, 43 associations and 7 subassociations that spread in oligotrophic, nitrophilous, hygrophilous or mesophytic biotopes. We obtained a total of 12 syntaxa that correspond to habitats of Directive 92/43/CE, some of them classified as priority habitats for conservation. It is present an approach to a dynamic-catenal model in which it is identified the response patterns of herbaceous communities to several disturbance factors. We conclude that the knowledge provided by Geobotany, namely by Synphytosociology, is an essential tool for the development of a sustainable management of the territory.