Ecological Modelling, 51 (1990) 1-28 1 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands TROPHIC DYNAMICS IN ECOSYSTEM NETWORKS: SIGNIFICANCE OF CYCLES AND STORAGE 1 BERNARD C. PATTEN, MASAHIKO HIGASHI 2 and THOMAS P. BURNS Department of Zoology and Institute of Ecology, University of Georgia, Athens, GA 30602 (U.S.A.) (Accepted 6 October 1989) ABSTRACT Patten, B.C., Higashi, M. and Burns, T.P., 1990. Trophic dynamics in ecosystem networks: significance of cycles and storage. Ecol. Modelling, 51: 1-28. Traditional Lindeman-Hutchinson trophic dynamics, which considers simple or acyclic (a) food chains and food webs without energy storage in compartments, is extended to the realm of compound or cyclic (to) ecosystem networks with storage. Paths of feeding networks are classified into first passage (~) and extended (mzdtiple) passage (c) 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 proper- ties 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 apyra- midal trophic structure of standing stocks, in which organisms at any trophic distance have about equal access to available energy resources. INTRODUCTION R.L. Lindeman (1942) and G.E. Hutchinson (1941) initiated traditional trophic dynamic theory as it is understood and practiced in ecology today. As biologists, they were interested in the complex 'food-cycles' such as Lindeman (1941) discovered in Cedar Bog Lake, Minnesota. Nevertheless, their mathematical analysis by 'progressive efficiencies' abstracted from 1 University of Georgia, Contributions in Systems Ecology, No. 79 and Okefenokee Ecosys- tem Investigations, Theoretical Series, No. 11. 2 Present address: Faculty of Science and Technology, Ryukoku University, Seta, Otsu 520-21, Japan. Elsevier Science Publishers B.V.