I am broadly interested in the interface between plant community and ecosystem ecology. In particular, I am interested in how the suites of physiological and life history traits present in a plant community affect ecosystem processes such as nutrient cycling and plant productivity. I focus on low fertility systems because these are places where autogenic feedbacks between plant and soil processes are likely to be the most important for community and ecosystem structure and function. Three general categories of questions have guided research in my lab:
1.) How do plant traits at the organ and whole plant-level scale to affect key ecosystem processes and when do these effects feedback to alter the success of individual species?
2.) How do community-level interactions modify effects of plant traits on ecosystem processes?
3.) When do changes in community composition increase the vulnerability of an ecosystem function to catastrophic change?
Through my research, I have taken a largely experimental approach to these questions, combining the techniques of community ecology and biogeochemistry. I have studied these questions in fire-disturbed boreal forests in Alaska and Siberia, in the moist acidic tundra of Alaska’s North Slope, in Hawaiian dry forests invaded by exotic grasses, and in epiphyte communities of wet tropical forest canopies. I have described several of these projects in detail below. Although their locations are quite different, my studies approach a unified goal: to better understand the fundamental role of plant traits in the nutrient dynamics of low nutrient ecosystems. I hope that through my research I can both increase our basic understanding of how ecosystems function, and improve our ability to predict how human-caused change in biodiversity and resource availability will alter terrestrial ecosystems.
– Michelle C. Mack