Abstract:
Twenty-eight musci species (Bryophyta) distributed in 16 Genera from Peninsula Fildes (King George Island, South Shetland Islands) are analysed both qualitatively and quantitatively, considering their dependence to: altitude and diversity of substrate, exposition and slope. The following parameters, measured by the indexes indicated in parenthesis, were considered: relative abundancy, spatial constancy, affinity (Jaccard and Winer), diversity (Shannon), uniformity (Pielou) and overlap (Horn). It is concluded as follows: The soil's substrate and the northern exposition increase the complexity of the muscinal taxocenosis; and the whole rock's substrate are clearly defining a taxonomic and biocenotic uniformity of musci. Five species are the most important, from an ecological point of view, in the analysed area: Drepanocladus uncinatus, Andreaea gainii, Tortula excelsa, Grimmia antarctica and Polytrichastrum alpinum. Six nuclei of species, with a high degree of affinity appear clearly defined, which are: Ceratodon minutifolius + C. grossiretis; Tortula grossiretis + T. g. varo atrata + Brachythecium turquetii; Schistidium apocarpum + Bryum sp. 2; Polytrichum alpestre + P. Juniperinum + Brachythecium antarcticum + Chorisodontium aciphyllum; Pollia heimii + Bartramia patens; Tortula tenella
+ Grimmia antarctica.