@article{oai:kpu.repo.nii.ac.jp:00004974,
 author = {米林, 甲陽 and Yonebayashi, Koyo},
 journal = {京都府立大學學術報告. 農學, The scientific reports of Kyoto Prefectural University. Agriculture},
 month = {Nov},
 note = {土壌中で有機物は無機成分と複合体を形成して安定に存在している。本研究は土壌中の粒径別有機・無機複合体について, 腐植と無機成分特に粘土との相互作用を解明し, さらに腐植化過程を複合体の腐植について明らかにすることを目的として行なわれた。土壌を粒径別に分画することで複合体中の腐植の組成的な複雑性は減少した。すなわち, 粒径の粗い画分には腐朽度の低い植物遺体が主に存在し, 腐朽が進みもっとも腐植化度の高まった腐植は粗粘土画分に存在した。細粘土画分には, 植物遺体の分解物や微生物遺体等が混入していると推察した。粘土画分の腐植はFe^<3+>およびAl^<3+>を介して粘土と複合体を形成していることが熱重量分析から推察された。粘土鉱物がモンモリロナイトの場合, 層間に腐植の一部が吸着していることをX線回折から明らかにした。カオリナイトの場合, 腐植は粘土表面のステップと外縁部(エッジ)に吸着していることを電子顕微鏡観察から明らかにした。なお, この場合吸着は偏在しており, 非晶質鉄, アルミニウムの沈積部位に偏りがあると考えられた。次に, 抽出腐植酸を分子量別に分画するための条件を検討し, 高分子腐植酸は球状凝集体を形成し, 低分子腐植酸およびフルボ酸は繊維状凝集体を形成することを電子顕微鏡観察から見い出した。さらに, 種々の粒径の無機成分と結合している腐植酸を抽出後, 分子量別に分画し, その光学的性質, 官能基量, 赤外線吸収スペクトルを測定した結果, 腐植化の進行は植物遺体の腐朽分解によってのみ進むものではなく, 植物遺体が分解され, 分解物が重縮合し, さらに酸化的解裂と酸化的重縮合反応がくり返されることによって腐植化が進行すると推察された。従って腐植化の最終産物は, 黒色調の著しい二重結合の平均的密度の高い官能基量のやや多い重縮合高分子腐植酸であると結論された。, In most soils a large proportion of the organic material reacts with the inorganic colloids to form the organo-clay complex. The present work was undertaken to investigate the interaction between humus and the minerals especially clay minerals and the humification process of humic acid in organo-mineral complexes. Four paddy soil samples were used; OK (polder land), TO (Humic allophane soil), LB (Grumusol) and RS (Acid sulphate soil). The soil was saturated with sodium ions, and then sonified in water suspension. After sonification the soil suspension was separated into various size organo-mineral fractions by successive sedimentation and centrifugation; <0.2μ clay-equivalent (fcx), 0.2&acd;2μ clay-equivalent (ccx), silt-equivalent (six) and fine sand-equivalent (fsx) complex fraction. 1) Experiment concerning the nature and properties of organic matter were carried out. Obtained results suggested that the low humified plant debris with wide C/N ratio was contained in fine sand fraction, and the most humified humus with narrower C/N ratio was concentrated as humus-coarse clay complex. Low humified organic materials with narrowest C/N ratio which were complexed with fine clay fraction would be result from the microbial debris accumulated in this fraction. 2) From the thermogravimetric (TG) analysis it was offered that the humus in the clay complex, except LB and RS fcx, were complexed with Al^<3+> and Fe^<3+>, and that the Al^<3+>-humus complex would be extracted with alkaline reagent selectively, so Fe^<3+>-complex would be remain in non extractable form as humin complex. In case of LB and RS fcx, TG study indicated that the humus in the complexes was in a closer association with clay, as compared to other clay complexes. 3) From the X-ray diffractometric evidence and the results of the glycerol sorption on clays and humus-clay complexs, it was offered that the natural sorption of humic materials occured in the interlamella spaces of montmorillonites in LB fcx and ccx. 4) The gold flash decoration method was applied to observe the surface microtopography of clay-humus complexes with electron microscopy. In case of kaolinite-humic acid complexes, abundant humic acid was observed on crystal edge and the steps on surface of some kaolinite particles. In naturally occurring humus-clay complexes too humic substances were adsorbed on clay in the same manner as above. Surface microtopography of humin complexes had etched marks. These may be due to the effect of alkaline reagent to extract the Al^<3+>-humus complex selectively. 5) Gel chromatography has been applied to fractionation or purification of soil humic acid, and gel-solute interactions due to aromaticity and heterocyclic rings of humic acids have been discussed. A suitable gel-solute system for the study of humic acid was looked for. Further, fractionated humic acids were characterized with respect to their buoyant density in sucrose density gradient sedimentation analysis, and their shapes were observed with electron microscopy. Electron micrographs of these fractionated humic acids showed that the diameter of granular aggregates tend to be smaller in the decreasing order of their molecular weight, and fluffy aggregates, which dominate in fulvic acid fraction, increased in the above order. 6) Humic acids were extracted and purified from the organo-mineral complexes described above, and fractionated on the basis of molecular weight differences by gel chromatography with proposed gel-solute system; high molecular weight (ca. 50000) and low molecular weight (ca. 10000-20000) fractions. These molecular weight fractions of humic acids were studied for their optical properties, IR spectra, C/N ratios and functional groups, as determined by colloid titration method. From these studies it was inferred that extinction coefficients of humic acids at 400nm indicated the π electron density, Δ log K values indicated the polymerization degree of aromat},
 pages = {121--171},
 title = {土壌中の有機・無機複合体に関する研究(農芸化学部門)},
 volume = {28},
 year = {1976},
 yomi = {ヨネバヤシ, コウヨウ}
}