Presenters: Emma Shelton
Authors: Emma Shelton, Dallas Johnson, Gabriela Chilom
Faculty Advisor: Gabriela Chilom
Institution: Dixie State University
Organic matter is a key component of the terrestrial ecosystem as it is responsible for many physical and chemical properties of soils, including retention of water and nutrients. Most of the organic matter input to soils is in the form of dissolved organic carbon. The amount, nature and persistence of the organic carbon sequestered by soil depends on the type of mineral matter present in soil. This project is investigating the potential for carbon sorption of four local soils, collected from the Utah-Arizona border. Batch isotherm experiments were used to determine the distribution of organic carbon between a soil sample (solid phase) and a concentrated solution of leonardite humic acid (liquid phase). The amount of organic carbon in the solid phase was measured directly by a CHN analyzer and was reported as mg organic carbon per g of soil. The chemical composition of the liquid phase before and after sorption experiments was analyzed by FT-IR. Comparative analysis of the amounts and nature of the organic carbon retained was performed for the four soils used.