Effects of Aluminum and Acidity of the Drift, Mortality, and Molting of Stream Insects

摘要

Responses of nine stream insects to short term increases of acidity and aluminum concentrations in artificial streams were studied. For the mayflies studied (Stenonema modestum Ephemerella subvaria and E. catawba) drifting behavior increased when aluminum concentrations were elevated above 1 ppm and mortality was increased at pH 5. Three of the four caddisflies studied (Hydropsyche ssp., Macrostemum zebratum, and Chimarra obscurra) were affected by increased salinities in high aluminum treatments, but were not adversely affected by short term increases in acidity or aluminum concentrations. Molting success of the insects was reduced by increased acidity.