Doctoral Dissertation Research: Long-Term Reconstruction of Oak Mast in the Southern Appalachian Region

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

Oak trees (Quercus spp.) in the southern Appalachians of the southeastern U.S. produce fruit in the form of acorns in most years. During some years, however, the production of acorns (also known as mast) is especially heavy for all oak trees in an area. These extreme mast events represent a significant resource expenditure for the trees, and they have profound impacts on wildlife and wildlife dynamics. The development of detailed longitudinal records of masting in the southern Appalachians is making available information that permits scientific examination of the dynamics of longer-term masting cycles and whether any changes have occurred in response to climate change or other factors. This doctoral dissertation research project will employ new methods for dendrochronological mast reconstruction to explore spatial aspects of masting in oaks in the southern Appalachians. One hundred-year mast histories will be developed for several locations in the southern Appalachians, and these reconstructions will be used to examine temporal trends in mast production, to explore links between climate and mast events, and investigate the spatial dynamics of mast events. The project will generate a set of long-duration oak chronologies that are spatially distributed throughout the southern Appalachians. Multiple chronologies will enable a spatial analysis of the effect of climate on tree growth by comparing individual stand records with twenty U.S. Historical Climate Network (USHCN) meteorological stations throughout the region. This project will contribute broadly to the development of dendrochronological techniques. The long-term mast reconstructions developed through this project will allow foresters, ecologists, and biogeographers to better understand mast ecology by looking back in time. The project also will add insights into the role of scale in the dynamics of natural systems. The analysis of masting at different scales will enhance understandings of the roles of driving mechanisms in mast dynamics. The mast records also can be used by wildlife managers to examine the role of mast in past wildlife population fluctuations and by ecologists to examine how extreme mast events contribute to oak-establishment pulses. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.