Brown Bag: Hazards of Organic Carbon

Bulk determination of organic carbon, nitrogen, and their stable isotopes is a frequently desired analysis of soils and sediments. Due to the occurence of inorganic carbon in many samples and the lack of a reliable on-line method to discriminate against inorganic carbon, samples must be pretreated to analyze only the organic portion of the total carbon pool. Removal of carbonates is typically achieved by acidification, but this alters nitrogen and, depending on the method, may alter carbon as well. Here, Hutchings presents a small side project of his graduate work: a comparison of pretreatment methods and their effects.