Herbaceous and subshrubby flora associated with palm grove ecosystem in the Pampas Biome

Abstract In southern Brazil there are remnants of natural populations of Butia odorata (Barb. Rodr.) Noblick (Arecaceae), palm groves locally known as butiazais. This work was developed in order to characterize the herbaceous and subshrubby assemblages associated to this ecosystem in the Tapes municipality (Rio Grande do Sul state), located in Pampa Biome, Brazil. Forty nine field trips were done from March 2011 to July 2013, when collecting flourished and/or fruited material. In the three hectares sampled in this study, 261 herbaceous taxa and subshrubs were found, corresponding to 170 genera belonging to 54 families. The most representative family was Poaceae (29 genera and 67 species), including a new species for the science, followed by Asteraceae (32 genera/49 species), Fabaceae (13/20), Cyperaceae (7/10), Orchidaceae (6/8), Iridaceae (5/8), Rubiaceae (5/8), Verbenaceae (4/5), Malvaceae (4/4), Cactaceae (4/4), Euphorbiaceae (4/4), Apiaceae (3/8), Melastomataceae (3/3) and Solanaceae (3/5). This area of native grasslands in association to the palm grove provides important ecosystem services that must be conserved. The results obtained in this study may provide the basis for the development of public policies related to the protection and management of the ecosystem of butiazal.