Effects of soil physical properties in deep vadose zone on the transport phenomena of mass and energy.

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The transport phenomena of mass and energy in deep soils, where the direct effects of climate changes and human activities on the ground surface hardly reach in a short time, have serious influence on both local and global natural environments. Researches on this issue, however, have been poorly improved, because the transport phenomena in deep soils have been dealt with in the border area among such fields as groundwater engineering, geology, soil mechanics, soil science, hydrology, and agricultural engineering. This study aimed to clarify the transport phenomena of mass and energy in deep soils by using both experimental and field studies.Five outcomes of this study are emphasized as follows :1.Gas Phases, such as CO2 and CH4, in deep zones of a wet land were detected both in a field and in a soil column. The importance of gas discharge by the outburst rather than by the molecular diffusion was dearly verified.2.Zero flux plane (ZEP) of soil water were detected through both experiments and simulations for the first time. The abrupt disappearance of the downward-shifting ZFP and subsequent upward soil water flow from deep soil zone was reported for the first time in this study.3.Rain water percolation in deep soil zone was analyzed to evaluate the excess water holding capacity in the vadose zone to design the buried water container underground. The modified formula from Guelf permeameter method was effectively applied.4.Mixing of grass fragment generated from waste and byproducts into soils were effective to maintain the high water permeability of intensively compacted soils in such a field like high school ground.5.A bio-venting technique was applied to re mediate contaminated deep zone soils by oil-like materials. The difference of the contact areas of microbes and ventilated air in soils affected to the remediation efficiency.