Incorporating phylogenetic information for the definition of floristic districts in hyperdiverse Amazon forests: Implications for conservation.

Juan Ernesto Guevara Andino,Walter Palacios,Nora Oleas,Hans Ter Steege,Paul V A Fine,Hugo Mogollón,Carlos Ceron,Nigel C A Pitman

doi:10.1002/ece3.3481

Abstract

Using complementary metrics to evaluate phylogenetic diversity can facilitate the delimitation of floristic units and conservation priority areas. In this study, we describe the spatial patterns of phylogenetic alpha and beta diversity, phylogenetic endemism, and evolutionary distinctiveness of the hyperdiverse Ecuador Amazon forests and define priority areas for conservation. We established a network of 62 one‐hectare plots in terra firme forests of Ecuadorian Amazon. In these plots, we tagged, collected, and identified every single adult tree with dbh ≥10 cm. These data were combined with a regional community phylogenetic tree to calculate different phylogenetic diversity (PD) metrics in order to create spatial models. We used Loess regression to estimate the spatial variation of taxonomic and phylogenetic beta diversity as well as phylogenetic endemism and evolutionary distinctiveness. We found evidence for the definition of three floristic districts in the Ecuadorian Amazon, supported by both taxonomic and phylogenetic diversity data. Areas with high levels of phylogenetic endemism and evolutionary distinctiveness in Ecuadorian Amazon forests are unprotected. Furthermore, these areas are severely threatened by proposed plans of oil and mining extraction at large scales and should be prioritized in conservation planning for this region.

Highlights

Ever since Wallace one of the main goals of biogeography has been the delimitation of biotic regions in order to circumscribe areas that are characterized by the same species pool and potentially by the same evolutionary, geological–historical, and ecological processes
Floristic inventories in the Ecuadorian Amazon have been influential in our understanding of the concept of hyperdominance and patterns of relative abundance of species in the Amazon as well as floristic disruptions triggered by geology (Higgins et al, 2011; Pitman et al 2008), suggesting that the assembly of the lowland Amazonian tree flora is the result of the interplay between edaphic specialization mediated by geological history and oligarchic tree communities
We present the results of an extensive one-hectare plot network that represents the most comprehensive spatial sampling of the trees of the Ecuadorian Amazon to date in order to evaluate the patterns of floristic affinities in this hyperdiverse region and provide insights into conservation priorities from a phylogenetic context

Summary

| INTRODUCTION

Ever since Wallace one of the main goals of biogeography has been the delimitation of biotic regions in order to circumscribe areas that are characterized by the same species pool and potentially by the same evolutionary, geological–historical, and ecological processes. There has been no systematic attempt to define floristic regions using approaches that include both compositional and phylogenetic diversity, which is likely to provide additional insights to improve research- based conservation policies Honorio In his pioneering work, Faith (1992) posited the concept of phylogenetic diversity as the sum of branch lengths of a phylogenetic tree along a minimum spanning path connecting the tips of the tree present in a location to its root. We present the results of an extensive one-hectare plot network that represents the most comprehensive spatial sampling of the trees of the Ecuadorian Amazon to date in order to evaluate the patterns of floristic affinities in this hyperdiverse region and provide insights into conservation priorities from a phylogenetic context.

| METHODS

Findings

| DISCUSSION