乾燥期間が土壌有機態窒素の無機化, 水稲の窒素吸収に及ぼす影響について

Mineralization of soil organic nitrogen and nitrogen absorption by rice plant as affected by drying duration

Creators Ando Ho

Creators Marumoto Takuya

Creators Wada Gensichi

Creators Nakamura Tutomu

The effects of moisture content of soil and drying duration on the mineralization of soil organic N and N absorption by rice plants were evaluated using paddy soils derived from alluvial sediment and volcanic soils in tropical and temperate areas. The results obtained are as follows : 1) The amount of N mineralized for 4 weeks incubation increased with the decreasing soil-to-water ratio. No significant difference was observed in the water content of soil when the drying duration was more than 4d. However, the longer the duration of drying, the greater the amount of N was mineralized irrespective of the soils' parent materials and the areas where it was obtained. 2) There were significant differences in the dry weight and amount of N in rice plants among treatments. The amount of N in rice plants increased with the increasing duration of drying up to 6 weeks. However, the dry matter increase of the rice plant grown in soil dried for 8 weeks was smaller than the other treatments despite the highest N mineralization observed in this soil. 3) The mineralization rate of soil organic N was higher at 1 or 2 weeks after incubation than at 3 or 4 weeks.

[ISSN]0029-0610

[NCID]AN00195767

[isVersionOf] [NAID]http://ci.nii.ac.jp/naid/110001748141/