Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)



Committee Chair(s)

James N. Long


James N. Long


Leila M. Shultz


Dave Roberts


John A. Bissonette


Allen Rassmusen


How plants from a common species pool form community has been considered from a variety of approaches. A promising approach involves the search for assembly rules based on plant functional traits. This approach has potential to provide insight into community and ecosystem processes In this research. a general and simple conceptual model based on life forms and independent of species is used as a framework for assessing the internal structure of plant communities. Plant functional traits are used to identify patterns within and between plant communities in the contrasting environments of Camp Williams, Utah, and Camp Grayling, Michigan.

The conceptual model has three different functional types formed by one to three functional groups. A functional group, made up of species with similar life form, is analogous to a vegetation stratum. A functional type, consisting of one or more functional groups. is analogous to a community or vegetation type.

Correspondence analysis (CA) and analysis of variance (ANOVA) indicate that richness, species diversity, and trait diversity are essentially independent of functional type and are, for example, fairly consistent regardless of climatic regime or structural complexity. Cover. on the other hand. increases with the number of functional groups in a functional type.

Consistent patterns and trends for sets of functional traits support the view that assembly rules may account for internal structure in plant communities. The consistent association of sets of traits with functional groups even in taxonomically dissimilar communities suggests that the functional traits are related to fundamental ecological processes that shape these communities.

Ambiguity in some of the results might be explained by extending the analysis to additional installations that replicate the climatic conditions found at Camp Williams and Camp Grayling.