1. POLLUTION EFFECTS ON INTERTIDAL MACROBENTHIC COMMUNITIES.
- Author
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Read, P. A., Renshaw, T., and Anderson, K. J.
- Subjects
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POLLUTION , *INTERTIDAL ecology , *SPECIES diversity , *SEASHORE ecology , *INDUSTRIAL contamination - Abstract
(1) Changes in macrobenthic community structure along a pollution gradient in the Firth of Forth, were observed and quantified using four different measures of 'diversity': the Shannon-Weaver index H"; Evenness index E; Fisher index α and the Probability of Interspecific Encounter PIE. (2) The significance of differences between beaches, between sampling stations and between seasons were assessed by analysis of variance. (3) The four diversity indices were found to be closely correlated one with another; PIE being the one nearest to the centroid of the low. (4) Similar changes were observed along the pollution gradient for each of H". &alpha and PIE but the Eveness index E reflected a somewhat different tendency. (5) Results show that gross pollution diminishes both 'dominance diversity' and 'species diversity', whereas more moderate pollution reduces 'species diversity but is less effective in regulating 'dominance diversity'. (6) Differences in diversity and abundance between traverses and between levels at any one site can be explained by reference to various environmental factors. (7) Temporal changes in species numbers and individuals are apparent at all sites and these are reflected in the PIE values. The smallest temporal changes in PIE are associated with a grossly polluted beach (a stressed community) whereas the largest relate to a relatively unpolluted beach (an unstressed community). This conflicts with the view that temporal change is large under physiological stress conditions in unstable environments and small under minimal stress conditions in physically stable environments. [ABSTRACT FROM AUTHOR]
- Published
- 1978
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