PARENT SESSION
Poster Session #14: Plant Competition.
Tuesday, August 7, 2001. Presentation from 10:30 AM to 12:00 PM. Exhibition Hall
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Multispecies competition among core, intermediate, and satellite species: A new approach.
Ely, Joseph1, Gibson, David1, Connolly, John2, 1 2
ABSTRACT- The lack of multispecies competition studies has been due to the complexity of the design and associated statistical analysis. Most designs currently employed use multiple pairwise mixtures. We use the Simplex-lattice (Axial) method which has the advantage that it represents a more realistic experiment as it relates to species mixtures and field conditions. The design models a response surface (e.g. biomass) over a factor space that represents multispecies mixtures. The overall goal of the study was to determine the effect of competition among seedlings of core (Danthonia spicata), intermediate (Tridens flavus), and satellite species (Aristida dichotoma) that typically occur in Illinois glades. Two-week old seedlings were randomly placed in four mixture proportions across three densities. There were six replicates of each mixture (n = 72). The number of vegetative and flowering tillers was recorded at four time periods. It is clear from this study that D. spicata, a core species, is the competitively most adapted. The other species have limited contributions. It is expected that many satellite and intermediate species will have limited effects in the community. This is consistent with the core-satellite species hypothesis.
KEY WORDS: Multispecies competition, core-satellite species hypothesis, simplex-lattice (axial) design, Illinois glades