This article draws attention to the potential of magnetic resonance imaging (MRI) for studies of patterns and mechanisms of water infiltration into soils, and stresses the vitally important need for collaboration between hydrologists, soil physicists and MRI experts. A brief introduction of the principles of MRI is given. This is followed by a review of the literature relating to nonpreferential infiltration, preferential infiltration exhibiting fingering and preferential infiltration involving a wide range of macropore flow. These differing degrees of complexity of infiltration dynamics require the employment of noninvasive and nondestructive techniques for their detailed investigation. Finally, an overview of applications of MRI to the detection of the spatial and temporal distribution of soil moisture and its changes is given. General conclusions are drawn from previous and current research, and the potential of the application of MRI to infiltration studies is summarized.
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