LAUSR

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.