Characteristics of ferrous iron forms in paddy soil with reference to development of the soil profile

This paper focuses on the vertical distribution and characterisation of pedogenic iron forms in a Gleysol- Histosol transect developed in a marshy area in the Danube-Tisza Interfluve, Hungary. Four soil profiles were investigated along a series of increasing waterlogging and spatial and temporal patterns of hydromorphic pedofeatures (characteristics of pedogenic iron forms) were recorded. Frequent and wide-range redox potential (Eh) changes caused the emergence of many types of redoximorphic iron features, including mottles, plaques and nodules. The forms of these features depended on the micro-environments determined by the vertical position in the soil profile and the presence of plant roots. The greatest iron enrichment occurred in the zone of most intensive and widest-range redox fluctuations. Increasing water saturation resulted the extension of gleyic pattern due to the existence of permanent reduction. Most of the features also showed annual variations during the varying periods of water saturation and aeration.

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Paddy Soil Profile Distribution of δ13C Subjected to Rice Straw Amendment and Burning

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.886.3 ◽

2019 ◽

Vol 886 ◽

pp. 3-7 ◽

Cited By ~ 1

Author(s):

Wutthikrai Kulsawat ◽

Boonsom Porntepkasemsan ◽

Phatchada Nochit

Keyword(s):

Organic Carbon ◽

Paddy Soil ◽

Soil Profile ◽

Management Practices ◽

Soil Depth ◽

Animal Health ◽

Soil Samples ◽

Residue Management ◽

Straw Amendment ◽

Stubble Burning

Paddy residues are the most generous agricultural biomass from the paddy cultivation, Paddy residues practices include crop residue amendment and in-situ burning. It indicated that residue amendment increased the organic carbon and nutrient contents in soil, However, an open residue burning is still a common practice in Thailand despite of strict law enforcements and proper education to farmers about its implications on soil, human and animal health The present study determined how residues management practices: residue amendment and stubble burning, influence the soil organic carbon by determining δ13C in paddy soil profile. The 30 cm depth soil samples from the naturally straw amendment and stubble burning paddy fields were collected in Chiang Khwan district, Roi-et province during 2017. The δ13C values with soil depth showed that residue management practices produce statistical differences in both soils. The δ13C values of soil samples from amendment and burning sites ranged from-23.19‰ to-17.98‰ and-24.79‰ to-19.28‰, respectively. Carbon isotopes differentiate clearly between amendment site (more positive values) and burning site (more negative values). The results from this study were in accordance with literatures which reported that the δ13C distribution in the soil profile can be applied to study in SOC dynamics as a result of different paddy residue management practices (amendment or burning). Further research is needed to confirm the validity of the stable carbon isotope technique in this type of studies.

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A Study of Weathering in a Soil Derived from a Biotite-Hornblende Rock

Clay Minerals ◽

10.1180/claymin.1970.008.3.07 ◽

1970 ◽

Vol 8 (3) ◽

pp. 291-303 ◽

Cited By ~ 52

Author(s):

M. J. Wilson

Keyword(s):

Chemical Analysis ◽

Soil Profile ◽

Ferrous Iron ◽

Ferric Ions ◽

Octahedral Sheet ◽

Thermal Methods ◽

Direct Transformation ◽

X Ray ◽

Surface Horizon ◽

Biotite Weathering

AbstractThe weathering of biotite in a sedentary soil profile developed on biotitehornblende- rock near Rehiran, Inverness-shire has been investigated by optical, X-ray, chemical, infrared and differential thermal methods. In the C horizon a direct transformation to hydrobiotite was observed. This involves oxidation of all the ferrous iron present and subsequent movement of ferric ions from the octahedral sheet. In the B horizon weathering proceeds to a fully expanded 14A phase and this was identified as interstratified vermiculite-chlorite in a 1:1 ratio. Chemical analysis indicates that this stage is accompanied by a substantial addition of magnesium, much of which goes to form the brucite-like interlayers. In the more acid surface horizon these interlayers tend to break down thus yielding a more vermiculitic product. The possible general implications of this type of biotite weathering are briefly discussed.

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Effect of phosphorus addition on soil colloidal phosphorus content in paddy soil profile

Acta Ecologica Sinica ◽

10.5846/stxb201406031147 ◽

2015 ◽

Vol 35 (24) ◽

Author(s):

赵越 ZHAO Yue ◽

梁新强 LIANG Xinqiang ◽

傅朝栋 FU Chaodong ◽

朱思睿 ZHU Sirui ◽

金熠 JIN Yi ◽

...

Keyword(s):

Paddy Soil ◽

Soil Profile ◽

Phosphorus Content ◽

Phosphorus Addition ◽

Colloidal Phosphorus

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Fractionation method of ferrous iron in paddy soil

Soil Science & Plant Nutrition ◽

10.1080/00380768.1969.10432778 ◽

1969 ◽

Vol 15 (1) ◽

pp. 28-37 ◽

Cited By ~ 11

Author(s):

Satoru Motomura ◽

Hajime Yokoi

Keyword(s):

Paddy Soil ◽

Ferrous Iron ◽

Fractionation Method

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Effects of Drying-Rewetting Cycles on Ferrous Iron-Involved Denitrification in Paddy Soils

Water ◽

10.3390/w13223212 ◽

2021 ◽

Vol 13 (22) ◽

pp. 3212

Author(s):

Yushuai Zhang ◽

Baokun Xu ◽

Jiangpei Han ◽

Liangsheng Shi

Keyword(s):

Organic Carbon ◽

Paddy Soil ◽

Ferrous Iron ◽

Ammonia Nitrogen ◽

Paddy Soils ◽

Jiangxi Province ◽

Complex Interactions ◽

Rapid Accumulation ◽

Soil Moisture Status ◽

Anaerobic Environment

Soil moisture status has an important effect on the process of denitrification in paddy soils. However, it is unclear how it affects the ferrous iron-involved denitrification. Here, the influence of drying-rewetting cycles on ferrous iron-involved denitrification in paddy soil were studied with batch experiments. The dynamics of nitrate, ammonia, Fe2+, Fe3+ and total organic carbon (TOC), as well as nitrous oxide (N2O) were investigated using the iron-rich paddy soil in Jiangxi province, South China. Results demonstrated that the denitrification rate dropped while ammonia nitrogen content (NH4+-N) showed a rapid accumulation in the drying period. In the rewetting period, organic carbon played two-side roles. Organic carbon and ferrous iron together provided electron donors to denitrification, and organic carbon simultaneously reduced ferric iron under anaerobic environment. There were complex interactions among organic carbon, nitrate and Fe2+/Fe3+ under drying-rewetting cycles. Soil rewetting led to denitrification flush, especially after a moderately long drying period, while excessively frequent drying-rewetting alternation was not favorable to nitrate denitrification.

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A Mössbauer study of the weathering of hornblende

Clay Minerals ◽

10.1180/claymin.1976.011.2.07 ◽

1976 ◽

Vol 11 (2) ◽

pp. 153-163 ◽

Cited By ~ 6

Author(s):

B. A. Goodman ◽

M. J. Wilson

Keyword(s):

Soil Profile ◽

Ferrous Iron ◽

Mössbauer Effect ◽

Ferric Iron ◽

Natural Weathering ◽

Hydroxyl Groups ◽

Mossbauer Effect ◽

Mössbauer Study

AbstractThe behaviour of iron in the natural weathering of hornblende in a sedentary soil profile has been investigated using the Mòssbauer effect. The spectra from samples at different stages of weathering show appreciable differences which can be accounted for if ferrous iron is lost preferentially from M(3) sites where it is coordinated to hydroxyl groups in a trans arrangement. Unlike biotite the proportion of ferric iron does not increase during weathering and this illustrates the difficulty with which the ferrous iron is oxidized in the amphibole structure.

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