TROPHIC DYNAMICS IN ECOSYSTEM NETWORKS - SIGNIFICANCE OF CYCLES AND STORAGE

Traditional Lindeman-Hutchinson trophic dynamics, which considers simple or acyclic (α) food chains and food webs without energy storage in compartments, is extended to the realm of compound or cyclic (ω) ecosystem networks with storage. Paths of feeding networks are classified into first passage (π) and extended (multiple) passage (ε{lunate}) types. A methodology is presented that accurately quantifies both types of energy flows, with or without storage, from one compartment to another. It is shown how increased cycling and storage both tend to increase the ratio of indirect to direct flows, and contribute to properties of network amplification and homogenization of energy availability over all trophic levels. These properties of realistic food webs are not present in the classical acyclic food chain paradigm. Consequences include an age distribution of energy within actual organisms, and an apyramidal trophic structure of standing stocks, in which organisms at any trophic distance have about equal access to available energy reurces. © 1990.