Showing papers by "Diane M. McKnight published in 1984"
TL;DR: In this paper, periphyton and benthic invertebrates assemblages were studied at the confluence of two Rocky Mountain streams, Deer Creek and the Snake River near Montezuma, Colorado.
Abstract: Periphyton and benthic invertebrates assemblages were studied at the confluence of two Rocky Mountain streams, Deer Creek and the Snake River near Montezuma, Colorado. Upstream from the confluence the Snake River is acidic and enriched in dissolved trace metals, while Deer Creek is a typical Rocky Mountain stream. In the Snake River, downstream from the confluence, the pH increases and hydrous metal oxides precipitate and cover the streambed. The algal and benthic invertebrate communities in the upstream reaches of the Snake River and in Deer Creek were very different. A liverwort, Scapania undulata var. undulata, was abundant in the Snake River, and although periphyton were very sparse, there were as many benthic invertebrates as in Deer Creek. Downstream from the confleunce, the precipitation of hydrous metal oxides greatly decreased the abundance of periphyton and benthic invertebrates. This study shows that in streams metal precipitates covering the streambed may have a more deleterious effect on stream communities than high metal-ion activities.
126 citations
01 Jan 1984
TL;DR: For a detailed description of blast zone lakes see as discussed by the authors... and the references cited in Section 2.1, Section 3.3.1.1] and Section 4.2.
Abstract: Introduction Description of blast-zone lakes Physical characteristics Chemical characteristics Inorganic constituents Organic constituents Biological characteristics Methods Results and discussion Dissolved and suspended organic carbon ... Spirit Lake and South Fork Castle Lake. Coldwater Lake St. Helens Lake Fractionation of dissolved organic material. . . Characterization of aquatic humic substances. Page Page 1 Results and discussion Continued 1 Identification of organic compounds ........ 15 3 South Fork Castle Lake 15 3 Neutral organic compounds ........ 16 6 Organic acids 18 6 Spirit Lake 18 6 Neutral organic compounds ........ 18 7 Organic acids 19 7 Coldwater Lake 19 7 Neutral organic compounds ........ 19 7 Organic acids 19 8 Toutle and Cowlitz Rivers 19 10 Summary and conclusions 19 11 References cited 25 11 Supplementary data 26 14
6 citations