Ecosystem ecology
Ecosystem ecology is the study of the movement of energy and matter through ecosystems. It is one of the fundamental disciplines of ecology. Ecosystem ecology operates at a scale above that of communities but it is defined more by subject matter than by scale.
Ecosystem ecology deals with locally defined ecosystems which exchange matter and energy with their surroundings. Ecosystem ecology concerns itself with such areas as nutrient cycling (especially the carbon, nitrogen and phosphorus cycles), Gross and Net Primary Productivity (GPP, NPP), trophic dynamics and food chains.