Extraction of Humic acid and Fulvic acid from Massasauga, Spring Grove and Brownlee Native Prairie Soils in Illinois

Carbon sequestration is the capture of carbon dioxide from the atmosphere and deposition into reservoirs. Exchange of carbon occurs continuously between atmosphere and soil. Soil organic matter is a heterogenous mixture of organic substances that has important role in determining soil productivity. Non-living, non-tissue soil organic matter is called humus. Humus is composed of humic and non-humic substances. Humic substances are classified as fulvic acid, humic acid or humin based on solubility. Samples of soils were collected from three native prairies and adjacently located cultivated soils. Humic acid and fulvic acids were extracted from these sites using International Humic Substance Society methods. Humic acid content of Massasauga, Spring Grove and Brownlee natural prairies were found to be 41.2 g/kg, 36.0 g/kg and 42.4 g/kg respectively, whereas the controls were 32.4 g/kg, 28.4 g/kg and 21.6 g/kg respectively. Fulvic acid content of Massasauga, Spring Grove and Brownlee natural prairies were found to be 10.0 g/kg, 4.0 g/kg and 4.8 g/kg respectively, whereas the controls were 5.6 g/kg, 2.4 g/kg and 3.2 g/kg respectively. Results were analyzed statistically for means using SAS 9.3 software. Statistical difference was observed in humic acid content of prairies and conventionally tilled soils. Fulvic acid was not statistically different. Future studies will use spectral techniques to examine humic and fulvic acids.