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The Denver fossil algae database were gathered from the inception of Denver Region in 1953 by Richard Rezak. His specialty was algae, carbonate platforms, and off-shore modern reefs. He developed a very useful litho-stratigraphic tool while studying Proterozoic algae and stromatolites in Glacier National Park. This lead to his studies of modern analogs in the Caribbean and South Seas. His catalogs were converted into digital form, Excel and Filemaker Pro database. The Catalog consist of 1001 fossil localities. His supplementary data has been added whenever possible - sources field map locality points, E&R files with enhanced faunal lists, as well as formal publications
1. The effects of phosphorus enrichment and grazing snails on a benthic microbial community that builds stromatolic oncolites were examined in an experiment at Rio Mesquites, Cuatro Ci´┐Żnegas, Mexico. Chemical analyses of stream water samples indicated that overall atomic ratios of total nitrogen (N) to total phosphorus (P) were approximately 110, indicating a strong potential for P-limitation of microbial growth. 2. Phosphorus enrichment involved addition of 5 ?mol Na2HPO4 L-1 to streamside microcosms receiving intermittent inputs of stream water while grazer manipulation involved removal of the dominant grazer, the snail Mexithauma quadripaludium. After 7 weeks, we examined responses in organic matter content,...
We evaluated and optimized three rapid methods for extraction of high-quality DNA from carbonate-encrusted microbial communities using modern calcifying oncolites built by cyanobacteria and diatoms in a high-calcium freshwater river. Pulverization, acid (HCl) dissolution, and chelator-mediated (EDTA) dissolution of the carbonate matrix were used and optimized to liberate microbial cells from their mineral encasing. This was followed by cell lysis and DNA extraction and isolation. HCl dissolution yielded no measurable DNA, probably due to hydrolysis, whereas pulverization and EDTA dissolution yielded averages of 3.5 and 7.8 μg per gram of sample, respectively, of high molecular weight DNA. These DNA isolates...


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