Geographical distribution of macrofauna on sublittoral sediments of continental shelves: a modified trophic ratio concept
Wildish, D.J. (1985). Geographical distribution of macrofauna on sublittoral sediments of continental shelves: a modified trophic ratio concept, in: Gibbs, P.E. (Ed.) Proceedings of the 19th European Marine Biology Symposium, Plymouth, Devon, UK, 16-21 September 1984. pp. 335-346 In: Gibbs, P.E. (Ed.) (1985). Proceedings of the Nineteenth European Marine Biology Symposium, Plymouth, Devon, UK, 16-21 September 1984. European Marine Biology Symposia, 19. Cambridge University Press: Cambridge. ISBN 0-521-30294-3. 541 pp., more In: European Marine Biology Symposia., more |
Abstract | A Trophic Ratio concept is proposed as one view of the spatial distribution of sublittoral macrofauna of continental shelves. The Trophic Ratio, TR% = CD/D + S) x 100, is based upon the difference in feeding methods utilized by deposit-(D) and suspension-feeding (S) macrofauna. Units other than numbers of species in a standard sample, such as density and production, may also be used but are less conservative and give different results. Some potential difficulties with the method include the facultative trophic behaviour of some macrofauna and the fact that trophic group typology is now outdated with the grouping not linked experimentally to the physical factors controlling feeding. Judged by criteria of utility and universal applicability, the trophic ratio concept is acceptable only if physical impoverishing factors, such as tide and wave erosion, are also considered. For continental shelf ecosystems, the method appears to be compatible with the temporal concept of succession of the functional concept of energy flow. A tentative modification of the trophic-group classification is proposed. |
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