水田土壤の微生物代謝に関する研究-1-

概要

論文の詳細を見る
The metabolic pathway of microorganisms, which are responsible for the development of reductive conditions, in water-lodged paddy rice soils was pursued by the estimation of Eh7, Fe++/Fe+++Fe+++ number of various bacteria, NH4+, NO3-, S--, gaseous components (02, CO2, N2, H2, CH4) and organic acids contained in the reduced layer. The results obtained were as follows: (1) In the earls stage of incubation process, Eh7 dropped rapidly and Fe++ was reduced, both aspects of these transformations thus forming a contrast. (2) The peaks of bacterial number followed in the order: firstly bacteria by plating, secondly those by the deep tube method and lastly sulfate reducing bateria after incubation. (3) Nitrate disappeared in the initial stage of incubation, and ammonia was liberated along with the progress of reduction. (4) After the reductive conditions reached a certain level, active sulfide formation initiated. (5) Speaking about gaseous metabolism, O2 disappeared within 1 day of incubation. Later, CO2 was evolved and accumulated from 4 to 9 days. After vigorous accumulation of CO2, the decrease of CO2 accumulated and evolution of CH4 occured contrastly, and H being concur-rently evolved. (6) The amount of organic acids produced within an incubation period of 2 to 9 days markedly decreased later. From the above results, it may be concluded that this is the first attempt made to typify respe_??_tive metabolic steps in the water-lodged paddy soils. This may be stated as follows: The 1st step: oxybiontic metabolism by aerobes or faccultatively anaerobes. The 2 nd step: unoxybiontic metabolism by faccultatively or strictly anaerobic heterotrophs. The 3 rd step: methane fermentation and sulfate reduction, in which CO2, H2, organic acids or alcohols, produced in the foregoing 2 steps or this step were consumed as metabolites.
社団法人日本農芸化学会の論文

水田土壤の微生物代謝に関する研究-1-

スポンサーリンク

概要

著者

関連論文

スポンサーリンク