Arbuscular mycorrhizal fungal communities of high mountain ecosystems of South America: Relationship with microscale and macroscale factors

Abstract

The high mountain ecosystems of South America represent one of the main hotspots of biodiversity. There is an increasing interest in disentangling global patterns of arbuscular mycorrhizal fungi (AMF). Recently studies postulated that the majority of AMF taxa are cosmopolitan, although community composition changes depend on microscale and macroscale factors. In this Chapter we reviewed the studies performed at high mountain ecosystems of South America analyzing the richness of morphospecies and structure of AMF communties in relation to microscale (host species, pH, N, P) and macroscale factors (latitude, temperature, precipitation). AMF communities differed in both scales being associated with sampling site, vegetation type or host identity. Glomeraceae and Gigasporaceae families were related to micro- and macro-scale factors, while Acaulosporaceae did not show significant relationships with neither micro- nor with macro-scale factors. At higher scales, AMF community composition of tropical and temperate ecosystems differed due to latitude, precipitation and temperature. Meanwhile, at lower scales soil characteristics and host species became the most relevant factors in differentiating AMF composition of sites. AMF communities of high mountain forests of South America are differentially affected by the particular characteristics of these environments instead of showing a cosmopolitan pattern.