Thinking big with whole-ecosystem studies and ecosystem restoration—a legacy of H.T. Odum

Whole-ecosystem studies are in situ ecological studies and experiments of such a spatial and temporal scale as to include most if not all processes of the ecosystem. Principles of self-organization and self-design are key to whole-ecological function and often do not occur as vibrantly or conclusively at smaller scale experiments. Ecological feedback caused by organisms (e.g., beavers, plants that manage hydrology, ecosystem engineers, top-down control), pulses caused by events such as fire and floods, and emergent ecosystem properties caused by human wastes, recycling, and hydrologic modification are difficult if not impossible to be properly studied in small-scale experiments. Large-scale whole-ecosystem studies were pioneered in the 1960s and 1970s by H.T. Odum and colleagues with large drop nets in Texas coastal bays, rain forests enclosures in Puerto Rico, created coastal ponds in North Carolina, and sewage application to cypress swamps in Florida. The study in Florida investigated effects of wastewater additions to wetland function in cypress domes but unexpected fire in the experimental area led to adaptive research and the study of fire in field research and models. More recently we have been engaged in whole-ecosystem experiments, partially inspired by the work of Odum, at created wetlands in northeastern Illinois to investigate effects of water turnover on ecosystem function and in Ohio to provide insight on the long-range large-scale effects of hydrology and macrophyte planting on ecosystem function. We have also carried out major ecosystem-scale studies in coastal Louisiana, investigating the value of these ecological systems in treating wastewater and restoring lost landscape in coastal Louisiana. These studies in the Midwest and Mississippi delta form the basis of determining design standards on creating and restoring wetlands in the Mississippi River Basin to reduce the Gulf of Mexico hypoxia and regain many lost ecosystem functions over a large part of North America.