fatsoils

Fatsoils is a term used to describe soils that contain an unusually high lipid content or other hydrophobic organic compounds, which give them distinctive physical and chemical properties. In many contexts the term is informal and not part of formal soil taxonomies; it is often used to describe soils where lipid-rich residues from plants, animals, or hydrocarbon contamination influence behavior in the field.

Formation and characteristics

Fatsoils can form where lipids accumulate and persist under reducing conditions, such as in certain wetlands, peatlands, or soils that experience repeated deposition of lipid-rich organic matter. In some cases, hydrocarbon contamination or natural hydrocarbon seeps contribute lipid-like compounds that coat mineral particles. The resulting soils often exhibit hydrophobic surfaces, crusting, and altered water movement. They may have high organic carbon content with a notable fraction of lipids, while mineral textures and mineralogy can vary.

Physical and chemical properties

A hallmark of fatsoils is reduced wettability due to hydrophobic coatings on particles, which can hinder water infiltration and alter soil moisture dynamics. Aggregate stability and soil structure may be influenced by the presence of lipids, sometimes promoting distinct surface crusts after rainfall. Nutrient availability can be affected, as some lipid-rich coatings impede contact between minerals and soil solution. Chemical characteristics vary with the source of lipids, ranging from naturally derived plant waxes to petroleum-related hydrocarbons.

Distribution and implications

Fatsoils are reported in diverse settings, including oil-rich regions, coastal wetlands with high organic input, and urban or industrial sites with hydrocarbon contamination. Their hydrophobic properties can pose challenges for agricultural use, seedling establishment, and erosion control. Management approaches emphasize addressing water infiltration issues and, where applicable, remediation of hydrocarbon residues; strategies may include soil mixing, amendments to enhance wettability, or bioremediation to reduce contaminant lipids.

Note

The term fatsoils is not universally standardized and may overlap with descriptions of lipid-rich or hydrophobic soils in various soil science contexts.