Several important research themes in my lab include:
Plant Controls on Biogeochemical Cycling.
Plants can have direct and indirect influences on ecosystem processes and soil environments. In boreal regions, I examine how mosses, particularly Sphagnum species, influence decomposition and nutrient cycling. In many regions, wetlands are vulnerable to invasive species invasions due to their hydrologic function. We are beginning to examine the role of invasive species on biogeochemical processes in wetlands of the Great Lakes basin.
Climate change and disturbance in boreal regions.
The boreal region is a landscape mosaic shaped by disturbances, but in many regions climate change has caused pronounced shifts in the frequency and severity of disturbances such as wildfire, permafrost degradation, and insect outbreaks. Fire has strong controls over carbon sequestration across boreal landscapes, and we are beginning to examine the influence of burning on other aspects of biogeochemistry such as mercury cycling. I am particularly interested in how fire impacts peatlands, given the large organic matter stocks that reside in these ecosystems. We also are very interested in rates of permafrost degradation, and the impacts of thaw on greenhouse gas emissions between ecosystems and the atmosphere.
Whole Ecosystem Experiments in Climate Change.
Given that many boreal regions are experiencing or will experience warmer and drier conditions, we are examining how wetland communities and biogeochemical processes will respond to changing climatic and fire regimes. We recently established a series of water table drawdown and soil warming experiments in fens in interior Alaska. This work is affiliated with the Bonanza Creek LTER site.