The eco-exergy-empower ratio can be regarded as a relation between emergy and information, where eco-exergy measures the stored information of an ecosystem. The relation between emergy and information in biological systems of different dimensions has been previously analyzed. Particularly, in his Crafoord prize lecture in Stockholm, Odum stated that the emergy/information ratio is a measure of the information hierarchy: the higher the energy hierarchy of a system, the higher the ratio in sej/bit. He also discussed the results of a comparison of four types of systems at different levels having the same number of bits of structural information. One thousand bits of molecular glucose, algae, forest, and science journal were examined. The production of the same quantity of information on different spatial scales requires quite different energy inputs. This gives a scale factor that cannot be obtained from simple energy analysis. The emergy/information ratio was greatest for the science journal, followed by the forest. Analyzing energy to information ratio, an inverse result was obtained. The relation between emergy and information used by Odum gives a good indication of general character but has problems related to the Shannon's index of information, namely that of not being able to distinguish among different level of organization: the unit according to which information is calculated is independent of its size and complexity. This is why the measure of information was replaced with eco-exergy, and a relation between eco-exergy and emergy flow was introduced to indicate the organization or structure of an ecosystem per unit of emergy flow.
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