La vegetación reófila del Nordeste Argentino. Las comunidades vegetales con Podostemaceae de la provincia de Misiones

Abstract

Northeastern Argentine rheophile vegetation. Plant communities with Podostemaceae of the Misiones Province. In the Misiones province, plants communities with Podostemaceae live in rapids and waterfalls of the streams beloging to two watersheds (Paraná and Uruguay rivers). The Mourera aspera Community is only found in the tracks going upstream the Iguazú Falls. On the rock submerged in tracks there grows a Community with Apinagia yguazuensis, relatively rare, and only found in the Iguazú river and in the streams Tabay and Yazá. On walls and at the foot of waterfalls and in certain rapids, communities with Podostemum spp. constitute the most singular rheophile vegetation: the Podostemum comatum Community in Cataratas, the Podostemum mülleri and Podostemum atrichum Communities peculiar to streams of the Paraná watershed, the Podostemum rutifolium and P. undulatum Communities of wide distribution in the watersheds of the Paraná and Uruguay rivers. The community Marathrum azarensis although it was only found in tributaries of the River Uruguay, also grows in the Parana River in the Corrientes province. Habitats conditions were analysed and the distribution of the communities as relates to watersheds was studied.