Tropical Dry Forest Compared to Rainforest and Associated Ecosystems in Brazil

The examination of arbuscular mycorrhizas in the different associated vegetation types at surface and deep soil layers and its participation in the resilience of soil ecosystems is important to increase our understand on natural ecosystems. Tropical dry and humid forests and their associated vegetation types were not fully investigated in South America. In Brazil, most types of dry and humid forests present high levels of AM association and high AMF diversity, with trap cultures being of great importance to detect more species. Arbuscular mycorrhizal abundance is lower in dry forests compared to rainforests; however, species richness is higher in those dry forests than in rainforests. The number of spores in rainforests can be greater than in dry forests, and a high diversity can be observed, but similar and different AMF species are found among different forest types. The Murundu fields, the Rupestrian grasslands and the Ferruginous fields associated to Cerrado biome also contain higher biodiversity, being pointed as hotspots for AMF diversity. In this chapter we present an analysis of AMF abundance and diversity in different Brazilian forests comparing some patterns of occurrence drawing on recent research. Studies on mycorrhizas have developed largely; however the identification of species and applications of AM in environmental issues are still incipient, thus, more efforts to fulfill this knowledge gap are needed to better understand the role and possibilities associated with the mycorrhizal symbiosis.