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USGS · 70179841

Chemistry of selected high-elevation lakes in seven national parks in the western United States

David W. Clow·Robert G. Striegl·Leora Nanus·M. Alisa Mast·Donald H. Campbell·David P. Krabbenhoft
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Abstract

A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky Mountain National Park) were very dilute; medianspecific conductance ranged from 4.4 to 12.2 μS cm -1 andmedian alkalinity concentrations ranged from 32.2 to 72.9 μeqL -1 . Specific conductances and alkalinity concentrations were substantially higher in lakes in the central and northernRocky Mountains parks (Grand Teton, Yellowstone, and GlacierNational Parks), probably due to the prevalence of more reactivebedrock types. Regional patterns in lake concentrations of NO 3 and SO 4 were similar to regional patterns in NO 3 and SO 4 concentrations in precipitation, suggestingthat the lakes are showing a response to atmospheric deposition.Concentrations of NO 3 were particularly high in Rocky Mountain National Park, where some ecosystems appear to be undergoing nitrogen saturation.

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BibTeXRIS

David W. Clow, Robert G. Striegl, Leora Nanus, M. Alisa Mast, Donald H. Campbell, David P. Krabbenhoft. 2002. Chemistry of selected high-elevation lakes in seven national parks in the western United States. https://doi.org/10.1023/a%3A1020102608378

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