PARENT SESSION
Symposium 2: Climate Change and its Consequences on Coastal Dune Patterns and Processes: What Are the Future Perspectives?
Organized by: ML Martinez and P Moreno-Casasola
Monday, August 4. 9:00 AM to 11:30 AM, SITCC Chatham Ballroom B.

Individual versus community processes and the impact of sea-level rise on pattern formation in a model of sand dune plant succession.

Feagin, R.^*,1, ¹ Texas A&M University, College Station, TX

ABSTRACT- A cellular automata model of species within a sand dune plant community on Galveston Island, Texas, USA was utilized to test ecological hypotheses regarding individual plant interactions and their impact upon community organization. Simulations demonstrated that both an environmental gradient and facilitative succession resulted in the formation of characteristic sand dune patterns. The results showed that the plant patterns were due to individual plant responses to their environment within their local neighborhood, yet these responses were constrained by the history of community development. The local neighborhood was related to ecological field theory. The ratio of the scale of environmental variability versus the scale of a plant's local neighborhood distance determined the relative importance of individual and community level processes in forming pattern. Additional hypotheses about sand dune pattern formation were tested, where alteration of the gradient by rising sea-level and global climate change constrained plants to a narrow habitat between hard structures and the forebeach, resulting in a breakdown of community organization.

Key words: succession, cellular automata, sand dune, pattern organization