Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Taxonomic Level and Sample Size Sufficient for Assessing Pollution Impacts on the Southern California Bight Macrobenthos.
Author Ferraro, S. P. ; Cole, F. A. ;
CORP Author Environmental Research Lab.-Narragansett, Newport, OR. Mark O. Hatfield Marine Science Center.
Publisher c1990
Year Published 1990
Report Number EPA/600/J-90/437 ;ERLN-N124;
Stock Number PB91-177188
Additional Subjects Environmental impact assessments ; Benthos ; Taxonomy ; Environmental monitoring ; Water pollution effects ; Sample preparation ; Classification ; Marine ecosystems ; Site surveys ; Water pollution sampling ; Experimental design ; Systematics ; Santa Monica Bay ; Reprints ; Southern California Bight
Library Call Number Additional Info Location Last
NTIS  PB91-177188 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 09/04/1991
Collation 14p
Macrobenthic data from samples taken in 1980, 1983 and 1985 along a pollution gradient in the Southern California Bight (USA) were analyzed at 5 taxonomic levels (species, genus, family, order, phylum) to determine the taxon and sample size sufficient for assessing pollution impacts on 5 measures of community structure. Two statistical designs were compared: a t-test for differences between reference and impacted stations where the error term was (1) among-year variation at the reference station (impact effects design), (2) replicate (within-station) sampling error (location effects design). The estimated statistical power (1-Beta) to detect impacts was a function of type and magnitude of impact, level of taxonomic identification, the statistical design, and the sample size (ni = number of sampling years at the reference station for the impact effects design, and nl = number of replicate samples per station for the location effects design). Four replicate 0.1 sq m van Veen grabs per station were needed to ensure community-wide, unbiased estimates of Shannon's, 1-Simpson's and McIntosh's Index. Family-level identification appeared to be a good choice for assessing pollution impacts at the study site as it ensured a high probability (1-Beta > or = to 0.80) of detecting intermediate or larger impacts on most (impact effects design) or all (location effects design) of 5 measures of community structure when ni and nl > or = to 4. The level of taxonomic identification and sample size should be considered along with other sampling variables (e.g. sample unit size, sieve mesh size) when seeking a statistically rigorous, cost-effective study design sufficient to meet pollution assessment objectives.