CHARACTERIZATION OF MACROPORE MORPHOLOGY IN A SANDY LOAM SOIL USING X-RAY COMPUTER ASSISTED TOMOGRAPHY AND GEOSTATISTICAL ANALYSIS

Our understanding of the factors affecting the leaching of chemicals such as pesticides and fertilizers into soils is limited, due in part to a lack of adequate non-destructive measurements of soil pore size distribution. The recent application of X-Ray Computer Assisted Tomography scanning to non-medical fields such as soil physics has allowed the development of a new and non-destructive technique with considerable potential for quantification of soil and water processes. The present study was undertaken to develop an innovative protocol for the characterization and visualization of soil macropores. It focuses primarily on the characterization of macropore morphology in large undisturbed soil columns using a 4th generation X-ray CAT scanner. The objective of the study is to assess, in quantitative terms, variations in the morphology of macropores as a function of depth. In order to evaluate these variations, the number of macropores, soil macroporosity, macropore size, hydraulic radius, and circularity h...

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