By, Dr. Ilya Gelfand, Research Associate, Kellogg Biological Station, Michgian igelfand@msu.edu When people ask me what I do, I need to stop for a moment to answer that for myself. What do I do? I have two types of answers: short and long. The short answer isn't very short either, since ecosystem ecology requires additional explanation. First, an ecosystem is defined as a community of living organisms living and interacting within their environment. Ecosystem ecologists need to study both living and nonliving parts and their interaction, or to study biogeochemistry: interactions between