Phytosociology of Atractylis cancellata and Micromeria microphylla communities in southern Italy with insights on the xerothermic steno-Mediterranean grasslands high-rank syntaxa

Romeo Di Pietro,Paola Fortini,Massimo Terzi,Giuseppe Misano

doi:10.3897/pls2021581/07

Abstract

In the present paper a phytosociological study on the dry grassland communities identified in the western sector of the Murgia Plateau (Murgia delle Gravine) and in the Lucanian badlands territory is presented. Forty vegetation releves were carried out using the Braun-Blanquet phytosociological approach. Two new associations characterized by a therophytic dominance, namely Lysimachio foeminae-Atractylidetum cancellatae and Campanulo erini-Micromerietum microphyllae, are described and discussed from a syntaxonomic and biogeographic viewpoint. In addition, new phytosociological data concerning the Petrosedum ochroleucum communities developed on limestone outcrops, the perennial Hyparrhenia hirta steppe-like grasslands of the low-altitude areas of the Murgia hills and the small-size Brachypodium distachyum therophytic communities are presented.

Highlights

Among the characteristic species of this order are included the majority of the annual species we found in the Lysimachio-Atractylidetum cancellatae, such as Atractylis cancellata, Brachypodium distachyon, Catapodium rigidum, Crupina crupinastrum, Euphorbia exigua, Linum strictum, Stachys romana
Two new associations were identified and described for the south-eastern sector of Peninsular Italy, namely the xerophytic annual grasslands and micro-garrigues dominated by Atractylis cancellata and Micromeria microphylla
The new association Lysymachio foeminae-Atractylidetum cancellatae was here classified in the alliance Onobrychido-Ptilostemonion stellati

Summary

Introduction

We formalized the proposal of two new phytosociological associations of therophytic grasslands dominated by Atractylis cancellata and Micromeria microphylla, two species which exhibit a restricted distribution in the Italian peninsula. The ephemeral communities that develop on limestone substrates or more generally on the neutral-alkaline ones that do not have an extremely limiting factor in the mineral component of the soil tend to be dominated by a group of wide-distribution steno-Mediterranean species occurring throughout the whole Mediterranean coastal and subcoastal areas.

Results

Conclusion