Environmental Characterization of Sedimentary Humic Substances and Organic Matter in Taiwan

Abstract

Total organic matter (OM), humic and fulvic acids in sediments collected from various locations were determined. In general, the contents of OM (range from 21.0 to 202 mg/g), humic acid (0.01 to 29.4 mg/g) and fulvic acid (0.03 to 10.4 mg/g) in sediments collected from reservoirs, lakes, riverine, coastal and open ocean including the Antarctic Ocean areas varied with locations. Extremely high values of OM were found in Tienchih (a high mountain lake) samples. The results of Antarctic Ocean sediments indicated that the higher the mud (99.09%) content in sediments, the higher the OM (from 33.0 to 125 mg/g), humic acid (0.51 to 1.37 mg/g) and fulvic acid (from 0.47 to 1.55 mg/g) values were observed. Sedimentary humic substances were also isolated, purified and analyzed for elemental compositions, molecular weights and carbon distributions. Higher percentages of a-alkyl carbon (polysaccharides) were found in fulvic acid, and high proportions in the alkyl carbon, a -alkyl carbon and aromatic carbon regions are found in humic acid. Some explanations for the findings have been given.