Ecological Metabolism

This phrase is understood as a process which maintains a population or community as an entity (Khailov, 1971). Particular metabolites act as signals , either attracting or repelling other fish, while others have trophic significance. The former have already been given close consideration in a number of books on behaviour and ethology, so need no further comment here. The latter captured the attention of researchers relatively recently. It was found that the uptake of metabolic products is an important factor that cements aquatic ecosystems, from plants to lower animals (protozoans, coelenterates, molluscs and some others). Metabolites that play a trophic role are inorganic 

The relatively modest importance of fish in trophic dynamics is greatly exceeded by their economic importance, and so by the research effort put in by workers from many countries. Further knowledge of the biology of fish is still required. Fish are also suitable subjects for the study of adaptation and evolution. Being a top link in the trophic chain, they can also serve as an indicator of the condition of the whole ecosystem. 

It should always be borne in mind that published figures for the ecological efficiency of food assimilated for production are averages from studies made over many years. The picture may be very different in years of shortage or plenty, when efficiency, especially as estimated in the period of growth and accumulation of lipid, differs a great deal from the average. 

Indications of the condition of living systems in ecology are similar to those in medicine, veterinary science and animal husbandry. The aim of research in this area is to be able to identify characteristics which can define the best possible state of organisms and populations, and can also signal and quantify deviations from it. Such indications should have high resolving power, so as to reveal the situation in deeply hidden processes within the biological systems. 

It should be borne in mind that the lipid index cannot characterize the food supply over the whole annual cycle, but only that in the period when lipids are accumulated rather than consumed. For warm-water fish of the southern European seas, this is the summer and autumn, while for cold-water fish such as the Black Sea and Mediteranean sprat, it is spring and summer. The food 

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Khailov, K. J. "Ecological Metabolism in the Sea" Naukova Dumka Kiev, 1971. 

These studies have revealed a number of cardinal aspects of microbial ecology (a) the complexity of bacterial ecosystems, (b) the number of organisms of hitherto undetermined taxonomy, (c) the existence of organisms that have not been cultivated, and (d) the difficulty of assigning metabolic roles to many of the genomic sequences that have been revealed. Some examples are given to... 

G. Stotzky, Influence of soil mineral colloids on metabolic processes, growth, adhesion and ecology of microbes and virus. Interaction of Soil Minerals and Natural Organics and Microbes (P. M. Huang and M. Schnitzer, eds). Special Publication Number 17, Soil Science Society of America, Madison, Wl, 1986, pp 305-428. 

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