Soil Properties Controlling Infiltration in Volcanic Soils (Tenerife, Spain)

Soil water infiltration is an important process whose behavior depends on external factors and soil properties, which vary depending on the type of soil. The present paper aims to establish which soil parameters determine the steady-state infiltration rate of six Soil Orders, all formed on volcanic materials-Andisols (nonallophanic, allophanic, vitric), Inceptisols (typic, andic, vertic), Alfisols, Vertisols, Aridisols, and Entisols (psamments, fluvents), and contribute to the differences between them. The study was conducted at 108 sites on the island of Tenerife (Spain). The steady-state infiltration rate was measured using a double-ring infiltrometer. The relationship between the soil properties and infiltration was studied using Principal Components Analysis and a multiple regression model. The research concludes that texture, bulk density, and structural stability play decisive roles. Clay content is the most influential factor across all the soils. It is of greatest importance for infiltration in Vertisols, vertic Inceptisols, and Alfisols and of least importance in vitric Andisols and Entisols. Bulk density is the second most decisive factor and determines infiltration principally in vitric Andisols and Entisols (high rho(b) values) and in non-vitric Andisols (low values). Structural stability mainly influences non-vitric Andisols, although texture is the factor that determines the biggest changes in this type of soil. Structural stability is also found to influence infiltration in Entisols, vitric Andisols, and Aridisols, although in these cases owing to their low values.