Ref ID : 1209
Siavosh M. Zand; Indexes associated with information theory in water quality. WPCF 48(8):2026-2031, 1976
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Diversity indexes associated with the information theory are among many tools and indexes utilized to give a better understanding of ecological systems. They are complements to established indicators of diversity, such as the number of individuals and species in a given sample. The usage of the diversity index as the sole indicator of the status of aquatic ecosystem needs more rigorous evaluation. In this paper it is suggested that (a) biological sample collection and analysis be standardized prior to the comparison among various aquatic systems of diversity indexes and their associated parameters. (b) the diversity index be expressed in sits per individual units rather than the presently used bits per individual; and (c) a more appropriate term, relative evenness e (Equation 11), be selected to replace redundancy R (Equation 9), or evenness E (Equation 10). Relative evenness, a ratio, is an expression in which Brillouin's and Shannon's Equations are not arbitrarily mixed; this ratio has a wider band than E. The initial naming of the "information content of a message" as the "diversity index" in biological collections might have been an oversimplification of a very complicated and intuitive diversity phenomenon. Other terms such as "information content of the collection" might have been more proper. However, a study of the combined values of the current diversity index in sits per individual or the ratio "relative evenness", the total number of species in the collection, and othiuve concept of diversity in biological collections.