Benthic macroinvertebrates in seven New Zealand lakes

Publisher Website
Google Scholar
Abstract
The benthic macroinvertebrate faunas of seven Rqtorua lakes (Okataina, Rotoma, Tikitapu, Okareka, Rotokakahi, Ngapouri, and Okaro) were investigated by Ekman dredge at monthly intervals between May 1970 and May 1971. The main groups present were molluscs, oligochaete worms, and chironomid larvae. Molluscs were absent from Tikitapu, probably because of low levels of HCO3 − and Ca++, and mussels were absent from Okaro, apparently because of excess organic material in the water. The eight species of chironomid found were of no value as indicators of organic enrichment. Annual mean standing crops of invertebrates per square metre were higher (>1000 individuals) in eutrophic Lakes Ngapouri and Okaro, but at levels of <600 individuals could not be used to distinguish between the oligotrophic and mesotrophic lakes remaining. Numbers of macroinvertebrates generally increased with increased depth of water in the oligotrophic lakes, but decreased with depth in the eutrophic lakes.

This publication has 13 references indexed in Scilit: