Bioquality Hotspots in the Tropical African Flora

Abstract

Identifying areas of high biodiversity is an established way to prioritize areas for conservation [1-3], but global approaches have been criticized for failing to render global biodiversity value at a scale suitable for local management [4-6]. We assembled 3.1 million species distribution records for 40,401 vascular plant species of tropical Africa from sources including plot data, herbarium databases, checklists, and the Global Biodiversity Information Facility (GBIF) and cleaned the records for geographic accuracy and taxonomic consistency. We summarized the global ranges of tropical African plant species into four weighted categories of global rarity called Stars. We applied the Star weights to summaries of species distribution data at fine resolutions to map the bioquality (range-restricted global endemism) of areas [7]. We generated confidence intervals around bioquality scores to account for the remaining uncertainty in the species inventory. We confirm the broad significance of the Horn of Africa, Guinean forests, coastal forests of East Africa, and Afromontane regions for plant biodiversity but also reveal the variation in bioquality within these broad regions and others, particularly at local scales. Our framework offers practitioners a quantitative, scalable, and replicable approach for measuring the irreplaceability of particular local areas for global biodiversity conservation and comparing those areas within their global and regional context.

Exploring the floristic diversity of tropical Africa

“…As indicated in the methods section, we suggest that RAINBIO is the largest and most accurate database for tropical African plant distributions, as we undertook numerous data validation routines, automatic as well as manual via numerous African flora taxonomic experts. Recently, another dataset has been published [51], comprising 3.1 million records for 40,401 vascular plant species across the whole of Africa. However, this dataset was assembled to test a new method of identifying areas of important biodiversity conservation (Star ratings) and has not been specifically used to explore tropical African plant biodiversity.…”

The important challenge of quantifying tropical diversity

“…Finally, a macroecological analysis such as Sosef et al’s, can be viewed alongside other investigations of data with a similar geographical scope, for example Marshall et al’s [10] recent assessment of rarity amongst the tropical African flora. Of course different compilations of data may share many of the same shortcomings, not least because some overlap in source material is likely, but as long as they are not interpreted too simplistically, complementary analyses such as Sosef et al’s [4] and Marshall et al’s [10] jointly advance understanding and are well placed to support the conservation of biodiversity in our rapidly changing world.…”

“…Of course different compilations of data may share many of the same shortcomings, not least because some overlap in source material is likely, but as long as they are not interpreted too simplistically, complementary analyses such as Sosef et al’s [4] and Marshall et al’s [10] jointly advance understanding and are well placed to support the conservation of biodiversity in our rapidly changing world. In particular they underline the pressing need for better understanding of the distribution and nature of tropical diversity.…”

A linear sequence to facilitate curation of herbarium specimens of Annonaceae

“…Storing collections according to any organising system remains indispensable as herbaria have retained their historic functions, being the basis for plant systematics and taxonomy, floristics and identification, assessment of botanical diversi ty, and teach ing . In additi on, s ci ent i fi c developments have unlocked new applications of herbarium collections, such as the characterisation of phenological responses to climate change (Willis et al 2017), the assessment of global rarity of plant species to guide conservation (bioquality; Marshall et al 2016), the sequencing of near-complete plastomes (Bakker et al 2016;Hoekstra et al 2017) and the targeted enrichment of nuclear genes (Hart et al 2016), both for phylogenetic and evolutionary studies.…”