Sitosol

Sitosol is a term that appears in a range of scientific and non-scientific texts but does not have a single, widely accepted definition in mainstream soil science. Because it is not part of the standard classifications (for example, the World Reference Base for Soil Resources or USDA soil taxonomy), its meaning is context-dependent. In some sources, it is used informally to refer to the soil solution, i.e., the liquid phase that exists in soil pores. In others, “Sitosol” may be a proper noun — a brand name, project title, or the name of a location — and carries no specific scientific meaning.

When used to denote soil solution, the term describes the water in soil that contains dissolved minerals, nutrients, organic acids, and other solutes. Its composition is controlled by soil texture, mineralogy, organic matter, moisture, pH, and biological activity. The soil solution governs nutrient availability to plants and microorganisms and participates in processes such as weathering, ion exchange, and buffering.

Measurement and relevance: In agronomy and hydrology, the soil solution is studied via suction cups (minisuction lysimeters), porous cups, or laboratory extraction methods. Parameters typically measured include electrical conductivity, pH, and concentrations of major ions (nitrate, phosphate, potassium, calcium, magnesium, sulfate, chloride). The concept informs fertilizer management, salinity assessment, and remediation strategies.

To avoid ambiguity, readers should consult the source for the intended meaning of Sitosol in that context. See also: soil, soil solution, soil taxonomy.