Plant Functional Diversity and the Biogeography of Biomes in North and South America

Abstract

The concept of the biome has a long history dating back to Carl Ludwig Willdenow and Alexander von Humboldt. However, while the association between climate and the structure and diversity of vegetation has a long history, scientists have only recently begun to develop a more synthetic understanding of biomes based on the evolution of plant diversity, function, and community assembly. At the broadest scales, climate filters species based on their functional attributes, and the resulting functional differences in dominant vegetation among biomes are important to modeling the global carbon cycle and the functioning of the Earth system. Nevertheless, across biomes, plant species have been shown to occupy a common set of global functional "spectra", reflecting variation in overall plant size, leaf economics, and hydraulics. Still, comprehensive measures of functional diversity and assessments of functional similarity have not been compared across biomes at continental to global scales. Here, we examine distributions of functional diversity of plant species across the biomes of North and South America, based on distributional information for > 80,000 vascular plant species and functional trait data for ca. 8,000 of those species. First, we show that despite progress in data integration and synthesis, significant knowledge shortfalls persist that limit our ability to quantify the functional biodiversity of biomes. Second, our analyses of the available data show that all the biomes in North and South America share a common pattern-most geographically common, widespread species in any biome tend to be functionally similar whereas the most functionally distinctive species are restricted in their distribution. Third, when only the widespread and functionally similar species in each biome are considered, biomes can be more readily distinguished functionally, and patterns of dissimilarity between biomes appear to reflect a correspondence between climate and Echeverría-Londoño et al. New World Functional Diversity functional niche space. Taken together, our results suggest that while the study of the functional diversity of biomes is still in its formative stages, further development of the field will yield insights linking evolution, biogeography, community assembly, and ecosystem function.

Common latitudinal gradients in functional richness and functional evenness across marine and terrestrial systems

“…Other geographically widespread clades or groups show a similar saturating pattern of FR with taxonomic richness at low latitudes, including New World bats [11], plants [12,48], mammals [5] and stream fish [13]. Thus, general drivers of a skewed pattern in FE across these disparate systems are likely to include a combination of differential diversification (origination and/or extinction of taxa within functional groups [9]), associated biogeographic dynamics and/or differential capacities among functional groups for finer subdivision or packing into ecological niche space [4], each of which we consider in the following sections.…”

An operational definition of the biome for global change research

“…evergreen needle leaf forest, deciduous broadleaf forest) (Churkina & Running, 1998) or by a combination of vegetation physiognomy and climate descriptors (e.g. tropical rain forest, temperate grassland) (Whittaker, 1975;Reich et al, 1997;Schultz, 2005;Echeverr ıa-Londoño et al, 2018). Alternatively, if a study aims at comparing or projecting ecosystem responses to external drivers, a functional definition of biomes may be more appropriate.…”

Phylogenetic diversity and environment form assembly rules for Arctic diatom genera—A study on recent and ancient sedimentary DNA

“…Alpha‐ and beta‐diversity measures can be obtained from taxonomic diversity (based on the number of taxa) as well as from phylogenetic diversity (based on the phylogenetic distance between taxa; Figure ). Assembly rules in minute life‐forms such as diatoms are less widely explored than in plants (Echeverría‐Londoño et al, ; Kraft et al, ; Swenson, ) or animals (Arnan, Cerdá, & Retana, ) and only a few empirical studies exist (Bennett, Cumming, Ginn, & Smol, ; Bottin, Soininen, Alard, & Rosebery, ; Rimet et al, ; Stoof‐Leichsenring et al, ). It is known that diatoms are unicellular eukaryotic minute life‐forms and environmentally highly sensitive (Alverson, ).…”