干拓地水田における硫化水素および硫化物の生成におよぼす硝安の影響

The purpose of this paper was to study the effct of ammonium nitrate on the inhibition of root injury of rice plant in a newly formed polder field. The experiment was carried out in a water-logged condition on the paddy field, and the original soils were assayed for(analyzed according to the items of) ferrous iron, hydrochloricacid- soluble sulfides, pH and Eh. The results obtained may be summarized as follows. 1)The effect of ammnoium nitrate on inhibition of hydrogen sulfide and sulfides, which could be determined by the decrease of hydrochloric-acid-soluble sulfides and ferrous iron, had deen noticeable for one or two weeks following the start of this experiment. 2)A relationship or inclination could not be found to exist detween pH and Eh, and the growth and yield of rice plant were as usual. 3)This experiment suggested that a proper additional dressing of ammonium nitrate durng the period of the growth of rice plant would be able to inhibit the formation of hydrogen sulfide and sulfides, and to increase the yield of rice plant.