Method to Evaluate "Uplandization" in Converted Field from a Paddy Based on Crystallinity of Free Iron Oxides

JARQ : Japan Agricultural Research Quarterly
ISSN 00213551
書誌レコードID(総合目録DB) AA0068709X
38-03-02.pdf168.58 KB

“Uplandization” is the process that changes the physical and chemical properties in a paddy field into those of an upland field. There is a transitional period when a paddy field is converted to an upland field. We propose a new method to evaluate the degree of “uplandization” based on changes in crystallinity of free iron oxides. The iron oxides influence soil physical and chemical properties such as soil microstructure or phosphate retention. Iron crystallinity is evaluated by the amount of iron extraction over 120 min by 1 mol L-1 pH 3.0 sodium acetate buffer, at solution to soil of 100 to 1 (Feac). Feac decreases in proportion to the period after conversion to upland cultivation. Feac is significantly correlated with phosphate retention properties and iron reducibility of soils under submerged conditions, but acid-oxalate-extracted iron, which is used to extract amorphous free iron generally, is not. For this reason, Feac is considered to be more suitable for evaluation of the history of uplandization.

作成者 TAKAHASHI Tomoki TORIYAMA Kazunobu

redox reaction

phosphate sorption

soil microstructure

公開者 Japan International Research Center for Agricultural Sciences
国立情報学研究所メタデータ主題語彙集(資源タイプ) Journal Article
開始ページ 155
終了ページ 159
DOI 10.6090/jarq.38.155
権利 Japan International Research Center for Agricultural Sciences
言語 eng