Dissertation Research: The sensitivity of kettlehole ecosystems to abrupt drought-induced transformation

Lehigh University, Bethlehem PA

Investigators

Abstract

Global circulation models predict enhanced hydroclimatic variability in the next century, likely exceeding the range of 20th century observations. Ecologists are faced with the critical challenge of anticipating potential ecosystem responses to these changes. This proposed dissertation research will use kettlehole basins in northern Wisconsin as model systems to study the effects of past hydroclimatic variability on ecosystem structure and function. The research is designed to test the hypothesis that peatland establishment and expansion in these systems is a threshold response to climate variability, in contrast to prevailing models that suggest limited climate sensitivity. Methods will include detailed paleoecological analyses of lake and peatland sediment cores from multiple kettlehole ecosystems. Paleoecological data will be integrated with information on basin morphology and landscape position to develop a model of kettlehole ecosystem dynamics under various global climate change scenarios. The proposed project will increase our understanding of the potential for ecosystem state-shifts in response to future climate changes. Results will help resource managers anticipate potential changes in kettlehole ecosystems in the coming century, as well as changes in the ecosystem services provided by these unique systems. In addition, the predictive model developed as part of this study will be coded in open-source software and equipped with an intuitive graphical user-interface, enabling access by resource managers, educations, and students.