Conexões andino-brasileiras: variações espaciais na diversidade funcional, filogenética e na sensibilidade a mudanças climáticas em ambientes de topo de montanha neotropicais

Abstract

Spatial variation in diversity results from the interplay of ecological and evolutionary mechanisms that operate across distinct spatiotemporal scales. Therefore, understanding the origin and maintenance of communities requires not only recognizing species identity but also integrating phylogenetic information and the functional composition of co-occurring species. South-American montane grasslands (i.e., páramos, puna, campos de altitude and campo rupestre) are great models for understanding community structuring. This is especially true because these systems are often treated homogeneously in the literature due to their similar physiognomic characteristics. However, little is known about the functional and phylogenetic composition of South-American montane grasslands, which limits inference possibilities regarding the evolutionary relationships between co-occurring species, the responses of these organisms to environmental changes, and the degree of sensitivity of each community. This study aimed to analyze the variation in functional and phylogenetic diversity among South-American montane (i.e., páramos, puna, campos de altitude and campo rupestre) and to understand how these mountainous environments resemble or differ in their sensitivities to climate change. To achieve this, we conducted a systematic literature review of four types of South-American montane grasslands. Our results point to clear differences in both functional and phylogenetic structure among Neotropical high-altitude grassland vegetation. While Brazilian environments showed high functional originality and low redundancy, the community of Colombian páramos exhibited an opposite pattern of functional structure, with high redundancy and low functional originality. Additionally, significant differences in the distribution of ecological strategies were also observed. For phylogenetic structure, each environment presented a unique pattern of phylogenetic clustering for campos de altitude species, phylogenetic dispersion for campo rupestre, and for páramos, it was not possible to observe a pattern of phylogenetic structure. Although we found different patterns of phylogenetic and functional structure among these communities, South-American montane grasslands can be considered equally sensitive to long-term climate changes, albeit through different mechanisms.