I am an ecosystem ecologist with a strong research background in terrestrial nutrient cycling, isotope ecology, and mycorrhizal-mediated plant-soil interactions that transcend traditional research boundaries.
My research often employs the use of natural contrasts, such as along natural environmental gradients that vary in temperature or nutrient availability, or across distinct forest types that differ fundamentally in the form and pathways of nutrient uptake. I've had the opportunity to work in: field-scale nutrient manipulation experiments in Panama and Alaska; decomposition experiments in remote ectomycorrhizal forests of Guyana; nitrogen preference experiments using isotopic tracers in the mountains of Panama; along fertility gradients and experimental settings in boreal spruce forests of Alaska and Sweden; and, along treeline elevational gradients in seven different countries. Thus my ecological perspective is truly global in nature.
But I am not just a field biologist. I also have over 14 semesters of teaching experience in a diverse array of laboratory and lecture courses including: botany, ecology, mycology, and plant taxonomy and am enthusiastic to involve undergraduate and graduate students in my research. To demonstrate this, I have recently become a faculty lecturer at Humboldt State University, where I lecture in General Botany, Mycology, and Plant Ecology.
I have developed a research program focused on exploring the biogeochemical constraints of plant nutrient acquisition that have included the adoption of novel wet chemistry techniques, the application and analysis of natural abundance stable isotope tracers, and global scale meta-analyses. In so doing, I pursue observational, experimental, and synthetic research aimed at understanding how elements cycle within and among terrestrial ecosystems.
I am currently completing papers from my postdoctoral research in David Wardle's Vegetation and Ecosystem Ecology Lab at SLU in Umeå, Sweden. This project involed collaborations with 14 interanational researchers and field work in seven countries. It seeks to uncover unfiying trends in above- and belowground ecosystem components across montane elevational gradients spanning tree-line transition zones (sites listed under the Montane link above). These ongoing international collaborations promise much exciting work to come.
I am particularly interested in:
Factors which control the functional ecology of ecosystems
- Nutrient availability
- Measurement of the quantity and forms of growth limiting soil nutrients
- Foliar metrics of soil nutrient availability
- How different climates and global change interact with or cause altered soil fertilities
- Above and below ground interactions among plants and microbes
- Role of below-ground organisms in resource acquisition (particularly ectomycorrhizae) and the controls over plant nutrition
- Mechanisms and global patterns of plant-soil feedbacks
- Macroecological patterns in mycorrhizal systems across gradients in climate or fertility
- Evolutionary and functional ecology of ectomycorrhizal fungi in the tropics
- Climatic variation in mycorrhizal dependencies
- Drivers of soil, fungal, and plant nitrogen isotope ratios
- Temperature controls over diversity and ecosystem function
- Indirect causes of montane tree line ecotones
- Evaluation of the relative importance of multiple drivers (nutrients, climate, age, etc.) through explicit linkage with theory and data
- Use of manipulative experiments with crossed factors along elevation, chronosequence, and fertility gradients
- Ability of elevation-as-a-proxy for temperature gradients to serve as global climate change natural experiements