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Oceanologica acta 1984, Vol. 7, N° 1, Gauthier-Villars, plaquette de 20,50x29,50 cm, 14 pages Très bon état - Pour les envois hors de France, la tafication «livre & brochure» pour les frais de port a disparue.Les frais de port annoncés correspondent à une moyenne. Ils seront calculés au plus juste en fonction du poids de votre article.…

Condizione: New.

Data on the abundance of 32 chemical elements in a large number of marine finfish, mollusc and crustacean species were subjected to a closer analysis in order to established a number of thier statistical characteristics and to search for possible interspecific links between the concentrations of various elements. The concentrations of the elements usually showed asymmetric frequency distributions: except for H and O, all median concentration values were lower than the average concentrations (the coefficients of skewness of the concentration frequency distributions are positive). The observed variations in element concentrations are best represented by log-normal frequency distributions. Out of the 276 possible element-pair combinations for 24 elements, it appeared that only 46 such element-pairs showed significant inter-specific relationships existing for the concentrations in which they occurred in various animal species. It seemed most plausible that the various elements in living matter simply occur in constant ratios. These ratios are not rigidly fixed but may show a fairly large intra- and interspecific variation. A distinction between essential, neutral and toxic elements does not find support in the available data. The biological concentration factors (the ratios between the biological concentration and the environmental concentration) of various elements increase towards lower environmental concentrations. The biological use of various elements is probably entirely determined by their functional properties and only slightly affected by their environmental availability. 8 pp., 3 figs, gr. 8.…

Condizione: As New. Unread book in perfect condition.

Condizione: New.

Condizione: As New. Unread book in perfect condition.