Complementary Models for Ecosystems

The ecosystem level of ecological research is fraught with conceptual difficulties that have contributed to faltering progress in theoretical development. An acceptance of multiple models for different aspects of ecosystems may assist in reducing this confusion. Two complementary models of ecosystems are suggested: the first based on energy, the second based on matter. Whereas the first follows from the second law of thermodynamics, the second complementary model derives from the chemical stoichiometry of the biota. These models can be developed independently but have many points of interaction. These points yield another series of predictions and hypotheses. While these complementary models serve as theoretical structures for much of the body of ecosystem concepts, they are not adequate by themselves. Other complementary models, perhaps centered on explicit linkages at the population and community levels, are necessary.