Demografia i conservació de Simethis mattiazzi, espècie d'interès per a la flora vascular de Catalunya

Abstract

Simethis mattiazzi is an atlantic distribution plant which arrived to Catalonia during postglacial times of the Quaternary period. Lately, with the beginning of climatic warming and the setting-up of Mediterranean climate in Catalan lowlands, its distribution has been reduced and only has been kept at la Selva's plain, due to its submediterranean climate with Atlantic tendency. Nowadays, it can only be found in some parts of la Selva's depression, many of them threatened by human activity. Recently, the Generalitat de Catalunya has catalogued this taxon as a vulnerable species. The main objectives of our study is to know the physiology and the conservation state of this taxon in Catalonia and identify the factors that benefit and disadvantage its propagation. For this reason, this study is divided into two large blocks. 1. The conservation status of the species in the plain of La Selva, information taken from:  The location, delineation and habitat characterization of all stocks of S. mattiazzi at La Selva's plain.  Scrutinizing the number of individuals and proportion of which are sterile, flowers and fruiting, to know the population's density and the capacity of the taxon to reproduce.  The effect of the diminishment in habitat quality, from the comparison of the number of individuals which are in areas of dense woodland compared to the number of individuals which grow in clearings and open areas. 2. Ex situ monitoring germination of seeds, information taken from:  The study of seeds' viability with the tetrazolium test, in order to know the dispersion capacity and maintenance of the species over time.  Monitoring of morphology and physiology during embryo development under different conditions of temperature, light and presence or absence of elaiosome, to find out which conditions must undergo to break seed dormancy and germinate.  The germination capacity of the species. The first results will help us to get a first idea of the cycle of the species and, especially, the ecological status of the taxon in Catalonia. These data will help almost immediately to develop a management plan to maintain it and, if possible, to propagate the species in our country.