Estimation of 3‐D Moisture Content Using ERT Data at the Socorro‐Tech Vadose Zone Facility

In this study, diesel was selected as a pollutant to study the migration and distribution rule of light non-aqueous phase liquid (LNAPL) in the simulated vadose zone. Saturation was regarded as a critical parameter to reflect the LNAPL migration and distribution rule. To get LNAPL saturation distribution figures, an image processing method of saturation was established to improve light-transmission technology, which can deal with digital camera images. Results showed that the vadose zone contains three areas from top to bottom, named dry media, transition zone and capillary zone. The system has two interfaces at which moisture content increased significantly. The significant increase in moisture content induced two apparent horizontal LNAPL diffusions in the two interfaces. Furthermore, the highly saturated LNAPL was mostly distributed near the wet interface, which lay between the dry media and the transition zone. Moreover, the downstream expansion of LNAPL in the capillary zone was promoted by groundwater flow, yet cutting off LNAPL supply could stop the downstream expansion after a period of time. The accuracy of this image processing method of saturation was verified by mass balance theory and reported a relative error of 4.38%.

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Experimental study on the effect of temperature and flux conditions on moisture distribution in vadose zone soil

Water Science & Technology ◽

10.2166/wst.2016.569 ◽

2016 ◽

Vol 75 (4) ◽

pp. 881-889 ◽

Cited By ~ 3

Author(s):

Jinguo Wang ◽

Hu Zheng

Keyword(s):

Moisture Content ◽

Vadose Zone ◽

Soil Depth ◽

Soil Column ◽

Moisture Distribution ◽

Effect Of Temperature ◽

Land Productivity ◽

Temperature Changes ◽

The Difference ◽

Study Laboratory

Moisture distribution in vadose zone soil is the most important parameter for land productivity and vegetation status of ecological systems, and is sensitive to temperature variation. In this study, laboratory scale tests were conducted to determine the effect of temperature on variation in moisture distribution in covered and uncovered conditions. The results indicated that soil moisture from 2.65 to 20 cm was positively correlated with temperature and temperature gradient, and the top 2.65 to 5 cm was dramatically influenced by temperature changes in both covered and uncovered conditions. The moisture content when temperature was increasing was higher than that when temperature was decreasing for the same temperature, when the film covered the top of the soil column. In contrast, the moisture content when temperature was increasing was lower than when the temperature was decreasing for the uncovered soil column. The difference between treatments was not maintained as soil depth increased.

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