The structure of pelagic marine ecosystems

Abstract

This article is part of Rapports et procès-verbaux des réunions Vol. 173.A steady-state theory is derived for the distribution of organisms by size in the pelagic zone of the open ocean. The theory explores the flow of biomass from the smallest- to the largest-sized organisms through a series of size classes arranged on an octave scale. This formalism leads to simple, analytic expressions for the structure of the pelagic ecosystem that are testable by direct measurement.The important parameters are those describing the weight dependence of metabolism and growth. The main conclusion, that biomass in a given size class decreases in a regular manner with increasing size, is in substantial agreement with data collected by other workers in the subtropical oceans.