OXYGEN REQUIREMENTS OF BENTHIC INSECTS AS DETERMINED BY MANOMETRIC AND POLAROGRAPHIC TECHNIQUES

Determinations of oxygen consumption at or near 20°C were made on immature, aquatic insects belonging to the orders Diptera, Ephemeroptera, Odonata, Plecoptera, and Trichoptera by manometric and electrochemical methods. The plecopteran Pteronarcys pictetii and the dipteran Tipula abdominalis had the lowest respiratory rates; all the Ephemeroptera had high rates. Trichopteran Pycnopsyche guttifer and Macronemum zebratum, odonatan Hetaerina sp. and Calopteryx sp., dipteran Atherix variegata, and plecopteran Paragnetina media had intermediate rates. The respiratory rates generally agree with the usual index-organism classification of these insects. Those with high rates have been found in clean water zones, while those with moderate and low rates, in recovery zones. The correlation was 0.8920 when the same 30 insects were examined by the Warburg and electrochemical, flow-through methods. The latter method is described. © 1969.