Abstract:
In this work, the influence of atmospheric-pressure air plasma on soil quality improvement has been studied. The practical plasma model has been designed to shape like a rake using spark plugs. The high-frequency AC high voltage has been varied at 9, 12, and 15 kV for plasma generation. The soil has been treated directly with air plasma for three consecutive days with a discharge time of 15 and 30 minutes once a day before using it for cultivation. Regarding the experimental results, air plasma significantly positively affects soil enhancement. The germination rate and length of the sprout of all the morning glory seeds cultivated in the plasma-treated soils have been higher than the one of the control group, which are up to 1.74, and 1.14 times higher than that of the control group, respectively. From the soil analysis, the Total Kjeldahl Nitrogen (TKN) content could be improved for all the plasma-treated cases. The best condition has been at 12 kV with a discharge time of 15 minutes, where the TKN has been 4.33 times greater than the one of the control group. Moreover, the pH of all the plasma-treated cases has tended to increase, resulting in more pH-balanced soils. © 2023, Chulalongkorn University, Faculty of Fine and Applied Arts. All rights reserved.