Journal Article

trait-based test for habitat filtering: convex hull volume

Schwilk, Dylan W., Ackerly, David D., Cornwell, William K.

2006

Overview

Community assembly theory suggests that two processes affect the distribution of trait values within communities: competition and habitat filtering. Within a local community, competition leads to ecological differentiation of coexisting species, while habitat filtering reduces the spread of trait values, reflecting shared ecological tolerances. Many statistical tests for the effects of competition exist in the literature, but measures of habitat filtering are less well-developed. Here, we present convex hull volume, a construct from computational geometry, which provides an n-dimensional measure of the volume of trait space occupied by species in a community. Combined with ecological null models, this measure offers a useful test for habitat filtering. We use convex hull volume and a null model to analyze California woody-plant trait and community data. Our results show that observed plant communities occupy less trait space than expected from random assembly, a result consistent with habitat filtering.

• Publisher: Ecological Society of America
• Subject: Animal and plant ecology / Animal, plant and microbial ecology / Biological and medical sciences / California / chaparral / community assembly / community ecology / community structure / Competition / convex hull / Ecological competition / Ecology / Ecosystem / Flowers & plants / Fundamental and applied biological sciences. Psychology / General aspects / genetics / Geometry / habitat filtering / Habitats / Leaf area / Models, Biological / plant / Plant communities / Plant Components, Aerial / Plant Components, Aerial - genetics / Plant ecology / Plants / Plants - genetics / Population ecology / Quantitative Trait, Heritable / seed mass / Species / specific leaf area / Statistical Reports / Synecology / Theory / trait / traits / Volume / Wetland ecology / wood density / woody plants