Native tree and arborescent species for Agroforestry Systems in the Uruguayan-Brazilian Pampa

Tree species are vital to Agroforestry Systems (AFS), and selecting species that are suited to local conditions is essential for achieving this system's objectives. In this study we characterized the phytophysionomies present in the Uruguayan-Brazilian Pampa Ecoregion in order to identify the most suitable species to include in AFS. In this sense we aimed to answer the following questions: i) Do the a priori defined phytophysionomies have a different species composition compared to the ecoregion? ii) Which environmental variables are related to species composition variation? iii) Which species are indicators of different phytophysiognomies? iv) Which native species are key for AFS implementation in these phytophysiognomies? We analysed floristic and environmental data from 106 sites across five phytophysiognomies using Non-metric Multidimensional Scaling (nMDS) and Analysis of Similarity (ANOSIM) and the Indicator Species Analysis (Ind Val). Results revealed significant differences in species composition between the phytophysiognomies, indicating that the predefined formations have distinct species assemblages. Indicator Species Analysis (IndVal) identified 136 species, of wich 27 were prioritised for AFS use, contributing to a total of 84 priority native species, including those with multipurpose uses. These findings highlight the importance of considering local phytophysiognomies when planning AFS with native species in this ecoregion.