... the inlet point was in the middle, the outlet point was at the corner, surface soil type was sandy loam, no fertilizer was added in 2007, the crop plant was Akita-Komachi Rice, and the planting ... related to denitrification rates in the apparatus were thought to be similar to those in the surface of paddy soil, because microorganisms in the apparatus were thought to have originated from the ... the outlet point, the height of which was fixed during the observation period. The water treatment apparatus was set just in front of the weir, and water levels in the paddy field and the apparatus...