Energy Flows in Populations and Communities of Aquatic Animals

Abstract

AbstractThe energy assimilated by single individuals of aquatic animals throughout their life times and by populations and communities of aquatic animals during the growth season has been studied with due regard for the definitive weight of the single individual and the mean biomass of populations and communities. Energy assimilated throughout life by invertebrates of different systematic positions, definitive size and life duration is about 2.5 times as high as the energetic content of their definitive mass. The energy flow in populations of benthic animals is about 5 times as high as the seasonal average biomass, and in populations of planktonic animals it is 40 times as high. The energy flow in bottom communities is almost 10 times and in planktonic ones 35 times as high as the average seasonal biomass of communities. Specific production (P/B coefficient per 24 h) for communities of bottom animals was 0.013 per 24 h. The average value of the K2 coefficient (net growth efficiency) calculated for an individual's life time is about 0.4 in populations of bottom animals, the K2 for vegetation seasons is 0.26, and for communities it is 0.2 (per vegetation season). Increasing complexity of the biological systems is accompanied by an increase in the specific energy flow and a decline in the efficiency of food energy utilization for production.