DISSERTATION RESEARCH: Historical dynamics of American beech at its northern range limit

University Of Notre Dame, Notre Dame IN

Investigators

Abstract

Climate-driven shifts in distribution towards higher latitudes are expected to occur for many tree species. The ability of a species to move will depend mostly upon dispersal and colonization by individuals from populations at the poleward edge of its range, and the details of these migration processes are likely to determine the genetic structure of the new populations for millennia to come, and hence their ability to adapt to their new environment. This research seeks to anticipate this future by examining the past northward migration after glacial retreat and the present genetic population structure of a dominant tree of the temperate deciduous forests of the eastern U.S., American beech. By analyzing genetic data from pollen and macrofossils preserved in lake sediments for thousands of years in Upper Michigan, the project will elucidate the important patterns of colonization by beech patterns and show how these led to patterns of genetic diversity. By further integrating these historical data with genetic analyses of beech populations today, the project will help understand the long-term genetic consequences of climate-driven migration. Understanding how climate change will affect forests and biological diversity is important to society, because we depend upon forests for many products and upon diversity for maintaining a well-functioning environment. The project will also contribute to forest conservation and management by helping suggest which populations are genetically at risk and need immediate conservation attention. Moreover, the project will train undergraduate students in the process of scientific research.