Biological equilibrium

The communities include in particular bacteria, lower aquatic plants (algae), higher aquatic plants, organisms fish feed on (e.g. water flea, amphipods etc.) and fish. They participate in the self purification of waters (reduction of residual pollution from effluent discharges like industrial drainage) and maintain the natural biological equilibrium. 

The application of chemical plant protection agents has enabled an exceptional increase in the productivity of agriculture and yields in plant production by 15-20%, on the other hand, it has distrubed the biological equilibrium it has unfavourable effects on the soil edaphon and the hydrosphere. 

CONCLUSION - CYBERNETIC CONCEPT OF THE MARINE BIOLOGICAL EQUILIBRIUM... 

The effect of the mass of microorganisms in contact with, or in extremely close proximity to, the plant roots and root hairs, varies widely. The products produced may be either beneficial or directly toxic (Bomer, 1960 Woods, 1960). The organisms themselves may have little or no effect or they may be parasitic in or on the roots. At any one time a condition of biological equilibrium or balance between the various groups of organisms present is likely to prevail. This equilibrium is, however, rather unstable... 

A possible weakness in this approach is the assumption of a biological equilibrium. Yet it is remarkable, when a general anaesthetic is being administered to a patient, how rapidly equilibration seems to occur. If the flow of anaesthetic gas is turned down, that patient at once achieves a measure of consciousness, and when the former flow-rate is resumed, the patient is very quickly back on the lower plane of anaesthesia. Actually, because of the complexity of the systems concerned, these are only steady states but, to a first approximation, Ferguson felt justified in treating them as equilibria, in order to make use of simple thermodynamic principles. 

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