Changes in water and habitat quality of Kordan Stream were examined using community structure and biotic indices at 3 sites during 2008-2009. This investigation resulted in inventories of benthic insect communities being obtained from this stream. It also resulted in two metrics being calculated from benthic insect communities. Of the metrics used, one indicated EPT taxa richness and one involved a biotic index, HFBI, for organic pollution. Water temperature, water velocity, water depth, dissolved oxygen, BOD5, pH, specific conductivity; phosphate and nitrate concentrations were within ranges usually capable of supporting a diverse biota. Samples were dominated by insects and yielded 142 macroinvertebrate taxa. The scores calculated for HFBI was lowest (4.67) and rated good water quality (some organic pollution probable) at site 1 and increased to 5.45 rated fair (fairly substantial pollution likely) at site 3. EPT ratings were "under a little perturbation " at three sites, suggesting high taxa richness and habitat quality in Kordan Stream.

This study tests if the coarse particulate organic matter (CPOM) mass was related to the invertebrate community structure in riffles and sandy pools of a fourth-order reach of a stream after partialling out the effects of physical characteristics of the sampled patches. Diversity and structure of the assemblages differed between habitats. In both, CPOM mass was positively correlated with total density and with all functional feeding groups excepting filterers. Redundancy analyses and variance partitioning procedures indicated that (1) CPOM stocks influenced the assemblage structure in both habitats, and (2) most of those effects were unrelated to sampling date and measured physical characteristics (water depth in sandy pools, Froude number and substrate composition in riffles) of the patches. 1.