Notes on Lindeman's Progressive Efficiency

Lindeman's (1942) progressive efficiency (E sub(p)), the ratio of assimilation by two adjacent trophic levels, has figured prominently in ideas about ecosystem energetics. Because of the apparent relationship between Lindeman's efficiency and the yield of any trophic level of interest, there was an early interest in the value taken by E sub(p) in natural ecosystems. Other widely known hypotheses about E sub(p) are that it increases from lower to higher trophic levels (Lindeman 1942) and that it is higher in mature ecosystems than in immature ecosystems (e.g., Lindeman 1942, Margalef 1968). Data bearing on these hypotheses still are rare, in part because of the difficulty in analyzing trophically complex natural communities and in part because the concept of trophic levels is now regarded by many as unworkable or uninteresting. Burns (1989) has once again raised interest in the trophic structure of communities by carefully redefining trophic levels and pointing out links to network analysis that may allow ecologists to analyze the trophic structure of communities quantitatively. Here, I extend Burns' approach to offer some general equations for Lindeman's progressive efficiency, discuss briefly the ecological factors that affect it, and use this information to reevaluate some of the classical hypotheses about E sub(p).