As humans, we rely on the processes that occur in ecosystems to provide us with important resources (clean water and fertile soil, for example). So do the organisms living in those ecosystems. Therefore, understanding what happens to ecosystems when changes occur is important for our own interests as well as those of other organisms. We need to know not only what happens, but how it happens. Understanding the mechanisms will help us predict what will happen under global environmental change without having to wait for it to happen.
The ecosystem process I specifically look at is nutrient cycling. The movements of nitrogen, phosphorus, and carbon through ecosystems are some of the most important processes that occur in ecosystems. The cycling of these nutrients rely on the organisms (plants, animals, microbes) living in that ecosystem, as well as geology, chemistry, and climate. If organisms, climate, and chemistry of the environment change, so will nutrient cycling. Changes to these cycles will, in turn, influence the organisms living there. (For example, too much nitrogen can be poisonous for soil animals.)
My research looks at how nutrient cycles will change due to global environmental change, and how organisms respond to those changes, not just in one particular ecosystem, but around the globe. I try to understand not just what happens, but how it happens, so that we can better predict the consequences of global change.