ISSN:
1365-2427
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
SUMMARY. 〈list xml:id="l1" style="custom"〉1Seventeen sites were each sampled six times over 2 years for macroinvertebrates. A range of physicochemical variables was also measured to determine which factors were related to the distribution of species.2Numerical classification of the faunal data indicated that four groups of sites or communities were distinguishable: lowland sites; sandy upland sites; cobble upland sites from the northern catchment; cobble upland sites from the southern catchment.3Multiple discriminant analysis and multiple regression analysis demonstrated that particle size of the sediment, concentration of dissolved ions and altitude were the physicochemical features that were most strongly associated with changes in the faunal distribution.4Abundances of shredders and predators did not vary between the site groups while those of scrapers, gatherers and filterers did: scrapers were most abundant at cobble sites while gatherers and filterers were least abundant on sand and increased in abundance downstream. The distribution of the feeding groups showed some similarity with that predicted by the River Continuum Concept, but the fact that the shredders did not decrease in abundance downstream was a notable difference.5Abundance of the total fauna at a site was inversely related to the amount of benthic organic matter. This feature is contrary to the pattern usually reported from rivers in the northern hemisphere.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2427.1985.tb00204.x
