Doctoral Dissertation: Forest Response to Climate Change: Integrating Seed Dispersal Models and Molecular Markers with the Paleoecological Record.

Duke University, Durham NC

Investigators

Abstract

0073171 Clark The range expansion by forest trees following rapid climatic warming during the early Holocene provides a useful analog for predicting the ability of trees to respond to future climate change. Currently, however, early Holocene migration rates determined from fossil pollen records can not be easily reconciled with models of seed dispersal. This dissertation research is an attempt to reconcile the historical record and the dispersal biology of common eastern deciduous forest trees. First, migration routes and glacial refugia based on the distribution of molecular markers (cpDNA haplotypes) throughout the modern range of Fagus grandifolia, Acer rubrum, and Quercus rubra will be reconstructed. Maps of Holocene range expansion based on molecular and pollen data will provide improved estimates of climate driven migration rates. This study will then evaluate the ability of seed dispersal models to account for these migration rates using a dispersal model developed by this research group. The model will be parameterized using the distribution of seedlings established in old-fields and closed forests. By integrating fossil pollen and molecular data, this study will develop a more complete record of historical change. Explaining that change in terms of dispersal biology will allow a mechanistic basis for evaluating future change.