Classification of rocky outcrops plant communities in the mountains of Central Argentina

Aims Classification of plant communities and identification of their diagnostic species in different types of rocky outcrops in mountains from Central Argentina. We also explored how these plant communities differ in their endemisms, chorotypes and non-natives species composition, as well as in rock chemistry, elevation and climatic variables. Location Cordoba Province, Central Argentina. Methods The study was based on 505 phytosociological releves collected from 2009 to 2019 using the Braun-Blanquet cover-abundance scale. The hierarchical ISOmetric feature mapping and Partition Around Medoids (ISOPAM) analysis was applied. The vegetation matrix was ordinated through isometric feature mapping (ISOMAP), and the geochemical and bioclimatic variables were related to the ISOMAP ordination. Results We identified 14 plant communities distributed in three main clusters. We recorded 59 endemic species at the national level and 28 narrow endemics, restricted to the study area and nearby mountains. The number of non-native plants was relatively low (26 species). Perennial herbs (221 species), grasses (97 species) and shrubs (68 species) were the most prominent life forms. Plant communities were associated with rock chemistry (carbonate and acidic rocks), and also with elevation and climatic variables. Conclusion This study highlights the remarkable heterogeneity of outcrop vegetation in Central Argentina. It reveals that elevation and rock type (geochemical composition) were relevant factors associated with the floristic composition of plant communities and also, that outcrop habitats comprise a high level of endemisms, as well as a low number of non-native species, suggesting a high value for the conservation of local and regional biodiversity

Southern Highlands: Fungal Endosymbiotic Associations

In South America (SA), Highlands above-treeline stretch along 7000 km in a North-South direction, occupying almost 694,000 km2, most of it is located in the Andean region except for 34,500 km2 in the Chaco region. In these Highlands are represented very particular ecoregions and phytogeographic areas in desertic, arid and semiarid biomes with characteristic vegetations composed by endemic plants. These Highlands are completely different from the ones found in Europe and Asia due to their proper biodiversity, climate, geographic position, geologic origin, and biogeography. Highlands in SA are suffering soil erosion, a retraction of their areas due to the advance of the agricultural-livestock frontiers and overgrazing, environmental deterioration by firewood extraction and the accumulation of mining toxic waste. Mountain ecosystems are huge-natural-environmental laboratories where it is possible to study important ecological unresolved hypothesis. The study of fungal-root-endophytes (mycorrhizal and dark-septate fungi), their colonization to native plants and how to enhance the resilience of soil ecosystems deserves special attention. Studies on fungal-root-endophytes have been carried out extensively worldwide; however, the research in Highlands are still scant around the world, especially in SA. This Chapter reviews and discusses fungal-root-endophytes colonization in Highlands of SA, and compared them to the worldwide knowledge.Fil: Lugo, Mónica Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Menoyo, Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentin

Structure and diversity of Arbuscular Mycorrhizal fungal communities across spatial and environmental gradients in the Chaco forest of South America

The Chaco forest is one of the most diverse ecosystems in South America andharbors different vegetation units with high levels of biodiversity. However, theinformation about how belowground communities are spatially structured acrossvegetation units in the Chaco forest is scarce. We aimed to analyze the variation oftaxonomic and phylogenetic diversity and structure of the arbuscular mycorrhizal fungalcommunities across different vegetation units of the Chaco forest. Arbuscularmycorrhizal fungi (AMF) richness showed significant differences between vegetationunits. The AMF community composition was being significantly structured bygeographic variables (i.e. wider scale), environmental variables (i.e. altitude,temperature and precipitation) and edaphic (i.e. pH and Nitrogen). In addition, the AMFcommunities in Chaco forest might be phylogenetically clustered compared to local(Córdoba Province), regional (South America) and global species pool. In general, avariation of AMF communities in the Chaco forest might be determined by the spatialconfiguration and environmental conditions.Fil: Grilli, Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Marro, Nicolás Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Risio Allione, Lucia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentin