Soil water diffusivity: A simple laboratory method for its determination

Soil water diffusivity (D) is an important hydraulic property that is fundamental to characterize unsaturated watertransport. Its determination is complex, time-consuming and requires expensive instruments. The objectives of this workwere: to propose a simple and low-cost laboratory methodology to d...

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Detalles Bibliográficos
Autores: Villarreal, Rafael, Lozano, Luis Alberto, Soracco, Carlos Germán, Filgueira, Roberto Raul, Sarli, Guillermo Oliverio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/55021
Acceso en línea:http://hdl.handle.net/11336/55021
Access Level:acceso abierto
Palabra clave:Unsaturated water movement
Sorptivity
Richards' equation
Descripción
Sumario:Soil water diffusivity (D) is an important hydraulic property that is fundamental to characterize unsaturated watertransport. Its determination is complex, time-consuming and requires expensive instruments. The objectives of this workwere: to propose a simple and low-cost laboratory methodology to determine D function; and to analyze the influence of soilmanagement systems on D and Sorptivity (S). The studied soil was classified as a vertic Paleudol. The first 10 cm of the soilunder three different management systems (T1: Natural grassland, T2: direct drilling, and T3: Polyphitic Pasture) was sampled.The samples were sieved and packed into horizontal columns. The columns were analyzed under horizontal infiltration and Dwas determined by variations of water content as a function of time for fixed positions, obtained from low-cost soil moisturecapacitance sensors. The results showed that the proposed methodology is valid in the studied soils. Soil management systemsignificantly affected D and S. They were greater for T2 compared with T1 and T3 (D varied between 0.00033 and 0.0321cm2.s-1). This means that the soil under T2 can transmit water faster under non-saturated conditions as compared with thesoil under grazing. In conclusion, the proposed methodology allowed to determine D in a simple and low-cost way, and todetermine the influence of these properties on productive conditions.