Abstract Detail

Ecology

Accumulation methods for species, trait, and phylogenetic diversity in the Cape Floristic Region.

Species accumulation curves plot the accumulated richness of individual species as a function of the number of surveys or samples within a region. These curves are a common way in which ecologists and botanists assess whether a region has been adequately sampled to arrive at an accurate estimate of the number of species given that exhaustive surveys are limited by time and resources. However, biodiversity encapsulates a broad set of axes extending far beyond species richness, such as the diversity of traits and evolutionary history. Few methods have been developed to examine the accumulation of these other aspects of biodiversity. For instance, do leaf traits accumulate at the same rate as species diversity or are species so similar in trait values such that accumulation in trait diversity occurs at a lower rate than accumulation in species. The spatial focus is useful for ensuring that enough samples are taken to compare the species richness of different habitats and regions without exhaustive sampling. However, these methods have been less developed from other viewpoints, i.e., were there enough surveys to sample all the species within a particular genus or family of interest? In this paper, I present novel methods to compare the accumulation of trait and phylogenetic diversity across relevé surveys in South Africa’s Cape Floristic Region (CFR). The CFR is a biodiversity hotspot located in the Southwestern Africa defined by its Mediterranean climate, nutrient poor soils, and dominant heath-like vegetation called Fynbos. The methods described rely on a resampling method of accumulation that compares species, leaf trait, and phylogenetic diversity with Rao’s diversity metric. I compare accumulated species and trait diversity split by different dominant plant families, e.g., Proteaceae, Restionaceae, and Ericaceae. Initial analyses suggest that while the Restionaceae and Ericaceae accumulate trait diversity at similar rates, their species diversity diverges with the Restionaceae accumulating greater number species compared to the Ericaceae. The Proteaceae tended to have slower rates of increase in accumulation for trait, phylogenetic and species diversity, reflecting a lower number of species and traits spread more evenly throughout sites.

1 - University of Connecticut, Ecology & Evolutionary Biology, 75 N. Eagleville Road, Unit 3043, Storrs, CT, 06269-3043, USA

Keywords:
Biodiversity
trait diversity
Accumulation curves
South Africa
phylogenetic diversity.

Presentation Type: Oral Paper
Number: EC08006
Abstract ID:714
Candidate for Awards:Ecological Section Best Graduate Student Paper