Organic carbon is a key component of the terrestrial ecosystem as it is responsible for many physical and chemical properties of soils, including water retention and wettability. Soil organic carbon storage may be increased by direct methods as adding manure or other organic amendments.
The goal of this study is to increase the carbon loading to the soils and test the effect it has on the water repellency of the soils. A series of batch sorption experiments with dissolved organic matter (Leonardite humic acid) and four local soils, collected from the Utah-Arizona border, was conducted to obtain enriched soils with a range of organic carbon loadings. The enrichment in soil organic carbon was quantified directly using a CHN analyzer. The water repellency of soils was subsequently assessed using water drop penetration time (WDPT) test and the molarity of an ethanol droplet (MED) test. Comparative analysis of the dependence of water repellency and enrichment of organic carbon in soils was performed for the four soils used.