Life Science Hour Seminar

Title:

High-latitude climate and changing cycles of the elements of life

Abstract:

Boreal and arctic ecosystems release carbon in response to more frequent fires, thawing permafrost, warming temperature, and increased precipitation. Carbon release from soils and lakes to the atmosphere is a well documented response to high-latitude change. However, uncertainty in projecting regional carbon budgets results from limited understanding of interactions of carbon dynamics with hydrologic and nutrient cycles. Our research suggests that hydrologic flowpaths draining Arctic hillslopes are conduits of carbon to both the atmosphere and downstream lakes and rivers. In addition, we document large gaseous emissions of nitrogen from nitrogen-limited boreal ecosystems, suggesting a potential constraint on vegetation growth anticipated under a warming climate.

About the Speaker:

Tamara Harms is an ecosystem ecologist and biogeochemist with interests in cycles of carbon, nitrogen, and phosphorus. She is an associate professor at the University of Alaska Fairbanks where she studies the effects of changing climate, hydrologic, and disturbance regimes on elemental cycles. She focuses on how hydrologic flowpaths mediate reaction and transport of materials and has worked in deserts, cities, and high-latitude ecosystems, all places where hydrologic connectivity is changing rapidly.