Determination of hydraulic properties of a tropical soil of Hawaii using column experiments and inverse modeling

Revista Brasileira de Ciência do Solo

Martina Sobotkova²  Michal Snehota²  Michal Dohnal²  Chittaranjan Ray¹ 

[1] ,Czech Technical University in Prague Faculty of Civil Engineering ,Czech Republic

关键词: automated apparatus;    infiltration experiment;    retention curve;    hydraulic conductivity;    Oxisol;    structured soil;    aparato automatizado;    experimento de infiltração;    curva de retenção;    condutividade hidráulica;    Oxisol;    solo estruturado;   

DOI  :  10.1590/S0100-06832011000400016

来源: SciELO

【 摘 要 】

A method for determining soil hydraulic properties of a weathered tropical soil (Oxisol) using a medium-sized column with undisturbed soil is presented. The method was used to determine fitting parameters of the water retention curve and hydraulic conductivity functions of a soil column in support of a pesticide leaching study. The soil column was extracted from a continuously-used research plot in Central Oahu (Hawaii, USA) and its internal structure was examined by computed tomography. The experiment was based on tension infiltration into the soil column with free outflow at the lower end. Water flow through the soil core was mathematically modeled using a computer code that numerically solves the one-dimensional Richards equation. Measured soil hydraulic parameters were used for direct simulation, and the retention and soil hydraulic parameters were estimated by inverse modeling. The inverse modeling produced very good agreement between model outputs and measured flux and pressure head data for the relatively homogeneous column. The moisture content at a given pressure from the retention curve measured directly in small soil samples was lower than that obtained through parameter optimization based on experiments using a medium-sized undisturbed soil column.

【 授权许可】

CC BY   
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