Soil organic carbon (SOC) is a summarizing parameter including all of the carbon forms for dissolved (DOC: Dissolved Organic Carbon) and total organic compounds (TOC: Total Organic Carbon) in soils.

Source:

“Status of the World's Soil Resources. Main Report |Policy Support and Governance| Food and Agriculture Organization of the United Nations .” Food and Agriculture Organization of the United Nations (FAO) and Intergovernmental Technical Panel on Soils (ITPS), 2015.