CGRG Bibliography of Canadian Geomorphology
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Author : Francis, D.R.
Date : 2005.
Title : Using midges to assess past climate change in New England and the Canadian Arctic.
Publication : Eos Transactions. American Geophysical Union Joint Assembly Supplement, Spring Meeting, 23–27 May 2005, New Orleans, Louisiana, USA.
Issue : 86(18):
Page(s) : NB21C-03.
Abstract
Paleolimnology has become an important tool in environmental monitoring programs because it can provide baseline data often unavailable by other means. Remains of midges (Chironomidae and other Diptera) have proven useful in paleolimnological biomonitoring of anoxic conditions, nutrient loading, toxic pollutants, and climate change. Analyses of lake sediment cores from Baffin Island highlight faunal changes during the Holocene and indicate warm conditions in the early Holocene. Diversity tends to be low in late-glacial sediments and then increases as climate warms and the landscape develops. In New England lake cores, the much more subtle climate change known as the Little Ice Age can be seen in changes in the chironomid fauna. Using midges as paleoindicators requires modern "training sets" that quantify larval midge distributions across environmental gradients. Surficial sediment samples collected for training sets contain head capsule remains from the whole lake and represent an integrated sample of the modern fauna. These techniques may be useful for investigating chironomid diversity. Typically, head capsule remains can be identified only to genus but since many rapid biological assessment methods take the Chironomidae only to the family level, collection of head capsule remains could be a useful alternative.
Bibliography of Canadian Geomorphology