PARENT SESSION
Poster Session 2: Forest Ecology
Monday, August 8, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal

Limiting similarity in a temperate forest tree community.

Lake, Jeffrey^*,1, Hubbell, Stephen¹, ¹ University of Georgia, Athens, GA, USA

ABSTRACT- Community niche structure and limiting similarity have been widely discussed theoretically, and demonstrated in some animal communities, but only a few studies have addressed these concepts in plant communities. Of those studies, very few have found evidence for limiting similarity (i.e., Stubbs and Wilson 2004). Furthermore, this problem is virtually unstudied in the context of tree communities. Here, we quantify the within- and among species distribution of variation in leaf functional traits in a temperate forest canopy tree community, and relate this information to community-level co-occurrence of species at several spatial scales. Thompson Mills Forest, Georgia, is a late-secondary Piedmont oak-hickory forest, dominated by several species of Quercus, Carya, Liriodendron, and Fagus. Leaf functional morphology traits, including specific leaf area, perimeter-area ratio (a measure of lobing), and petiole length: blade area ratios, are used to characterize the trees. Within individual plasticity, ontogenetic changes, and within species variability are considered in addition to among species differences. Spatial analyses occurred within neighborhoods, areas, and the broader community. Results are mixed; species show differentiation for mean trait value in SLA, but strong overlap among species suggests a limited role for niche structure. Leaf shape parameters, especially those related to lobing, show more evidence of discrete species-level differentiation.

Key words: niche, limiting similarity, community structure, forest ecology