Trophodynamic phasing in theoretical, experimental aud natural pelagic ecosystems

Abstract

It is a great honour to be awarded the Oceanographical Society of Japan Prize for 1988 and to be provided with this opportunity to review our work on trophic relations in the pelagic environment of the sea. Many Japanese colleagues have participated in Canada on our experiments. These persons include Drs. H. Seki, M. Takahashi, A. Hattori, T. Ikeda, I. Koike, M. Ohtsu, S. Ichimura, K. Iseki, E. Matsumoto, N. Handa, Y. Maita, and others without whom our work on marine ecosystems would have assumed much less importance. In addition, the visit of Professor M. Uda to Nanaimo in 1959, and his lectures on fisheries oceanography, have always been an inspiration to me in the practical application of oceanography. For me, work on trophodynamic relationships grew out of my early association with Dr. J.D.H. Strickland who initiated some ecosystem studies using large plastic bags in the 1960s (Strickland and Terhune, 1961; Strickland, 1967). The CEPEX program (e.g. Parsons, 1978), which was started about a decade later, gave us the first real opportunity to break away from laboratory studies, where only species which generally grew best were studied, and to perform studies under near natural conditions on multiorganism communities. The purpose of this program was to provide some answers to practical problems as well as to gain a fundamental understanding of biological oceanographic processes. This program was started at a time when a large number of stories were circulating (e.g. Heyerdahl, 1975) that man was about to kill life in the oceans through pollution. In a practical sense what I believe that the CEPEX program showed was that the oceans were much more resilient than had been supposed. The effect of many kinds of pollutants tested during this program was to change the course of ecosystem interactions but not to cause the elimination of life. The scientific value of these experiments went much further in giving us time series data about how the physical/chemical environment interacts with different trophic levels. For the first time, the biological oceanographer was liberated from the hopeless entanglement of time and space in the sea, and it was now possible to follow population dynamics of planktonic organisms (Mullin, 1982).