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

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.

Two new species of Otoba (Myristicaceae) from Colombia

“…Otoba often is abundant within their habitats (Hartshorn 1983;Gentry 1993;Macía and Svenning 2005;Guevara Andino et al 2017;Honorio Coronado et al 2019). Illustrating this abundance, it is often one of the most collected genera in Gentry plots (i.e., those in which all plants with stem diameters equal to or exceeding 2.5 cm diameter at breast height along ten 2 × 50 m transects are documented) (Phillips and Miller 2002).…”

Forest Diversity and Structure in the Amazonian Mountain Ranges of Southeastern Ecuador

“…Ecuador is considered one of the 17 mega-diverse countries of the world [1]; the diversity of plants throughout its territory being a consequence of distribution patterns and geodynamic processes which have been studied during the last decades. The Ecuadorian Amazon is widely known for its great diversity of plants and animals and the determined peaks of diversity have been recognized worldwide [2,3]. Regretfully, anthropic pressure, determined by changes in land use and deforestation, make it one of the most endangered ecosystems, and therefore a priority for conservation [4].…”

Niche evolution of the Neotropical tree genusOtobain the context of global biogeography of the nutmeg family, Myristicaceae

“…Otoba occurs in many different habitat types in the northern Neotropics, and spans a broad elevational range that includes the highest elevation occurrence in Myristicaceae (Jaramillo-Vivanco & Balslev, 2020). Species can also be found in lowland rainforests, and Otoba is one of the ten most abundant genera in western Amazonia (Guevara Andino et al, 2017; ter Steege et al, 2006). Individual species can be some of the most common in many forests, including O. parvifolia in Madre de Díos, Peru (Pitman et al, 2017; Swamy, 2017) and Madidí, Bolivia (Macía, 2008), O. glycycarpa in Yasuní, Ecuador (Guevara Andino et al, 2017), and high várzea forest of the Amazonian floodplain in Brazil and Bolivia (Wittmann et al, 2006).…”

“…Species can also be found in lowland rainforests, and Otoba is one of the ten most abundant genera in western Amazonia (Guevara Andino et al, 2017; ter Steege et al, 2006). Individual species can be some of the most common in many forests, including O. parvifolia in Madre de Díos, Peru (Pitman et al, 2017; Swamy, 2017) and Madidí, Bolivia (Macía, 2008), O. glycycarpa in Yasuní, Ecuador (Guevara Andino et al, 2017), and high várzea forest of the Amazonian floodplain in Brazil and Bolivia (Wittmann et al, 2006). This broad ecological tolerance and presence across both notable Neotropical geographic features makes Otoba a great system to understand the roles of dispersal and niche evolution in the establishment of a widespread, ecologically important group.…”

“…They grow in many mesic habitats, including lowland tropical rainforest (both terra firme and floodplain), premontane forest, and cloud forest, spanning a broad elevational range (i.e., 0-2500 m) that includes the highest elevation occurrence in Myristicaceae (Jaramillo-Vivanco and Balslev 2020). Individual species of Otoba are among the most common in many rainforests, including O. parvifolia in Madre de Díos, Peru (Swamy 2017;Pitman, Vargas, and Terborgh 2017) and Madidí, Bolivia (Macía 2008) and O. glycycarpa in Yasuní, Ecuador (Guevara Andino et al 2017) and high várzea forest of the Amazonian floodplain in Brazil and Bolivia (Wittmann et al 2006). Otoba is one of the ten most abundant genera in western Amazonia (ter Steege et al 2006;Guevara Andino et al 2017).…”