Padrão de diversidade beta de macrófitas aquáticas do Pantanal de Mato Grosso

Abstract

Macrophytes are commonly known for their key role in maintaining and functioning aquatic ecosystems through increased environmental heterogeneity in shallow lakes, nutrient cycling and biomass production. Understanding the mechanisms and processes that driven to species distribution and diversity over time and space has been one of the biggest challenges for ecologists. The objective of this thesis was to evaluate the beta diversity pattern along environmental (i.e. water and sediment) and spatial gradients in 49 of subtropical floodplain lakes adjacent to the Cuiabá River, in the northern Pantanal of Mato Grosso. Aquatic macrophytes, physico-chemical variables (i.e water and sediment) and geographic coordinates were sampled. From this information, two manuscript were constructed using different analytical approaches combined with information of the species, functional and phylogenetic features. In the first manuscript, we investigated the local contribution (LCBD) and the individual contribution of the species (SCBD) to beta diversity, based on the approach of Legendre & De Cáceres (2013). In addition, we relate LCBD values to species richness and environmental and spatial variables. While SCBD values were reported with the number of sites occupied by each species and their functional group. In the second manuscript, we explored through distance-based redundancy analysis (db-RDA) and variance partitioning the different components of replacement and richness difference based on species information, functional and phylogenetic characteristics of aquatic macrophytes. Taxonomic beta diversity was governed mainly by replacement, while functional beta diversity was more related to richness difference. Phylogeny beta diversity was also explained by the two components of beta diversity. We found that environmental and spatial factors drove together to shape the different facets and components of beta diversity. Overall, both approaches provide new insights into the processes that have driven beta macrophyte diversity in floodplains. This information can be used to guide ecological assessments, restoration and conservation planning of the Pantanal and other wetland areas across the world.