共查询到20条相似文献，搜索用时 46 毫秒
1.
Masanori Mitsuchi 《Soil Science and Plant Nutrition》2013,59(3):249-259
To characterize the nature of humus in paddy soils, a comparison was made between the properties of humus in paddy soils and those in adjacent unflooded arable soils. Rice cultivation generally brought about a considerable increase in organic matter and in the PQ-value, with the exception of Andosol-paddy soils in which organic matter tended to decrease somewhat and the PQ-value remained virtually unchanged. The humification degree of humic acid as judged from Δ log k and RF values was generally lowered by rice cultivation except in the case of Yellow soil-paddy soil in which humic acid was originally low in the degree of humification. The accumulation of poorly humified humic acid may be a characteristic feature common to all paddy soils. These changes by rice cultivation are observed only in the upper part of the profiles, and seem to be associated with seasonally flooded conditions ot paddy soils. Iron oxides accumulated in subsurface soil have virtually no effect on the properties of humus. 相似文献
2.
运用野外调查与实验分析相结合的方法,对不同生长发育阶段红松人工林（林龄25、45、58、68 a）和红松混交林（林龄60a）根际与非根际土壤有机质含碳量、腐殖质组成与结合形态进行了研究。结果表明:不同年龄阶段红松人工纯林、红松混交林土壤有机质含碳量、腐殖质各组分含碳量随土层深度的加深而降低,并且根际土壤高于非根际土壤。就土壤腐殖质组成而言,除林龄58a红松人工林根际土壤和45a红松人工林非根际土壤外,其他林型土壤胡敏酸含碳量均高于富里酸含碳量;胡敏酸与富里酸比值（HA/FA）在1.00～2.45之间;土壤重组腐殖质、松结态腐殖质、稳结态腐殖质含碳量大小顺序为林龄58>68>25>45a;红松混交林除紧结态腐殖质外,其他腐殖质各组分含碳量均高于红松人工林。 相似文献
3.
M. KROSSHAVN I. KÖGEL-KNABNER T. E. SOUTHON† E. STEINNES 《European Journal of Soil Science》1992,43(3):473-483
Four samples of soil organic matter and their humic acids, fulvic acids and humin were studied with solid-state 13CP MAS NMR. The whole soil samples were fractionated using NaOH and HCl in order to extract humic acids, fulvic acids and humin. This investigation indicates that conventional humus fractionation does not significantly change the content of different functional groups in soil. 相似文献
4.
不同培肥方式黑土腐殖质形态特征研究 总被引：2，自引：1，他引：1
针对吉林省黑土区存在的土壤有机质下降、耕地质量退化等问题,利用公主岭国家黑土肥力与肥料效益监测基地连续20年的长期定位试验,采用核磁共振波谱分析法(NMR)、红外光谱分析法(IR)等现代分析方法,研究了不同培肥途径耕层土壤腐殖质的组成、形态结构及动态变化趋势。结果表明:不同培肥途径对耕层土壤腐殖质特征影响明显。施用玉米秸秆处理(S+NPK)和施用有机肥+轮作处理(M+NPK+R)均显著增加了土壤胡敏酸中脂肪族结构成分,单施有机肥处理(M+NPK)显著增加了土壤胡敏酸中羟基含量,S+NPK处理游离羧基含量显著增多。S+NPK、M+NPK及M+NPK+R处理,土壤富啡酸的甲基、亚甲基和次甲基结构成分显著增多,游离羧基含量也显著增多。单施化肥处理,浸提的富啡酸中无机碳酸盐和硅酸盐成分明显增多,化肥长期施用导致土壤中游离富啡酸数量显著减少,土壤的耗竭式利用,导致土壤中铁、铜结合态或络合态的富啡酸增加。不同培肥方式对黑土胡敏酸和富啡酸的元素组成影响有较大的差异,但均可引发胡敏酸C含量降低,N含量增加,富啡酸C、N、H含量增加,O含量降低,可通过不同的培肥方式对土壤腐殖质的元素组成进行调节。 相似文献
5.
The distribution of phosphorus among humus acid groups in different soil types was studied. It was shown that the binding of P with acid-soluble and-insoluble organic components is determined by the acid-base status of soils, which controls the predominant interaction of P with Fe and Al or with Ca and Mg, and the solubility of the resulting organic phosphates in acid and alkali. The major part of P is associated with the group of humic acids (HAs) in the acid soils and with fulvic acids (FAs) in the neutral and calcareous soils. During the fractionation of organic matter from acid soils, the amount of P redistributed from the HA to the FA group can increase with an increasing acid or alkaline impact on the soil, which breaks the bonds of the phosphorus-bearing organic components with metals. 相似文献
6.
长期施用有机肥和磷肥对潮褐土土壤有机质及腐殖质组成的影响 总被引：8，自引：0，他引：8
采用长期肥料定位试验,研究了施用有机肥和磷肥对土壤有机质、腐殖质含量与组成的影响。结果表明:与本试验布置时的基础土样相比,连续10年隔年施用有机肥、有机肥和磷肥配施使土壤有机质增加了8.4%~17.3%,单施磷肥土壤有机质下降了7.8%~10.7%,其差异均达显著水平;与P0M0相比,单施磷肥、有机肥、有机肥和磷肥配施处理的土壤中有机质分别增加了2.9%~6.2%、24.8%~29.8%、25.2%~35.1%;土壤腐植酸总量及胡敏酸含量与土壤有机质含量呈显著正相关关系;施用磷肥利于土壤富里酸的积累,并影响土壤胡富比。 相似文献
7.
The role of amino acids and nucleic bases in turnover of nitrogen and carbon in soil humic fractions 总被引：4，自引：0，他引：4
Y.V. KUZYAKOV 《European Journal of Soil Science》1997,48(1):121-130
Incorporation of labelled 15N and 14C amino acids and nucleic bases into soil humus fractions as well as humus turnover was investigated under field conditions. The dynamics of 15N and 14C incorporation into organic matter was characterized by the following main steps: rapid incorporation of the labelled substance prevailing for the first 1–3 weeks, and decomposition of included labelled fragments prevailing beyond one month after substance addition. The annual turnover rates of N and C in humus fractions due to incorporation of amino acids and nucleic bases were calculated. The turnover rate of N in humus is two to three times that of C. The contribution of amino acids to organic matter generation is about twice as great as that of nucleic bases and other N-containing organic substances. This indicates the important role of amino acids in the humification process and humus turnover. Turnovers of humic acids (0·002 year?1 for C and 0·02 for N) are the most rapid of humic fractions investigated, and humin is characterized by the slowest turnover (0·0002 year?1 for C and 0·007 for N). There are no significant differences in the turnover rates of fulvic acid fractions (0·0002 year?1 for C) with different molecular weight. 相似文献
8.
Almendros G Kgathi D Sekhwela M Zancada MC Tinoco P Pardo MT 《Journal of agricultural and food chemistry》2003,51(15):4321-4330
Humic matter in virgin and cultivated Vertisols and Arenosols from Pandamatenga (northern Botswana) has been studied by chemical fractionation and visible and infrared derivative spectroscopies. The in vitro soil respiration was also determined. Soils contained <15 g of total C kg(-1) and displayed scant mineralization activity. In Vertisols, cultivation has led to scarce significant changes in humus characteristics, pointing to a noteworthy resilience of the organic matter. Humic acids showed a very dark color, indicating a large concentration of aromatic structures and stable free radicals. Infrared spectra were featureless and alike. This strong structural stability is also suggested by Curie-point pyrolysis of humic acids, which failed to yield substantial amounts of diagnostic products, mainly in the case of Vertisols. Some unexpected similarities between Vertisols and Arenosols indicate that the influence of external factors on the humic acid formation processes prevails on that of the geological substrate. In Pandamatenga soils only small amounts of recalcitrant C and N forms are sequestered; they represent stable pools relatively independent from short- or medium-term climatic changes or management practices. 相似文献
9.
长期施肥对小麦-玉米作物系统土壤腐殖质组分碳和氮的影响 总被引：7，自引：1，他引：6
通过对华北平原小麦–玉米轮作农田生态系统18年田间施肥试验,研究了长期不同施肥处理对耕层（0—20 cm）土壤腐殖质及活性腐殖质组分碳和氮的影响。试验设化肥NPK不同组合（NPK、NP、NK、PK）,全部施用有机肥（OM）,一半有机肥+化肥NPK（1/2OMN）及不施肥（CK）共7个处理。结果表明,各施肥处理均能在不同程度上增加土壤腐殖质（胡敏酸、富里酸和胡敏素）及活性腐殖质（活性胡敏酸和活性富里酸）组分碳和氮含量,提高可浸提腐殖质（胡敏酸和富里酸）及活性腐殖质组分碳和氮分配比例;但施肥对土壤活性腐殖质组分碳和氮含量的增加率均分别高于腐殖质组分碳和氮。各处理土壤腐殖质及活性腐殖质组分碳和氮含量均为OM处理最高,且有机肥与化肥NPK配施高于单施化肥各处理;而化肥处理中NPK均衡施用效果最好。说明施用有机肥、有机肥与化肥NPK配施及化肥NPK均衡施用是增加土壤腐殖质及活性腐殖质组分碳和氮的关键;活性腐殖质组分碳和氮较腐殖质组分碳和氮对施肥措施的响应更灵敏。 相似文献
10.
The chemical composition of aquatic humus was investigated by permanganate oxidation. Both methylated and non-methylated samples were investigated and the results compared with those of different soil humic fractions investigated earlier.The total amount of oxidation products identified from the methylated sample was 2%, and from the non-methylated sample 0.9%. The composition of the oxidation products from methylated aquatic humus was 42% benzenecarboxylic acid methyl esters (8 different compounds), 43% methoxy-benzenecarboxylic acid methyl esters (12 compounds), 10% dimethoxy-benzenecarboxylic acid methyl esters (4 compounds), and 5% of 1, 2, 3-propanetricarboxylic acid trimethyl ester. The unmethylated aquatic humus yielded 84% benzenecarboxylic acid methyl ester (7 compounds), 7% methoxy-benzenecarboxylic acid methyl esters (2 compounds), and 9% of 1, 2, 3-propanetricarboxylic acid trimethyl ester. Three diazines isolated from methylated material were believed to be artefacts from diazomethane treatment. Two of the diazines have earlier been found by oxidation of methylated soil samples, the third, C10H12N2O6, is an oxidation product of methylated aquatic humus only.Oxidation of aquatic humus yielded more benzenecarboxylic acids and methoxy-benzenecarboxylic acids than soil humic fractions, and less dimethoxy-benzenecarboxylic acids. No aliphatic dicarboxylic acids were detected among the oxidation products of the aquatic humus.The compounds identified are mainly the same as those found by oxidation of different soil humic fractions, although their yields clearly demonstrated that the aquatic humus differed in composition from the soil fractions. 相似文献
11.
The carbohydrates in soil organic matter seem to be derived from undecomposed or partially decomposed plant and microbial residues, In soil, these carbohydrates exist chiefly in such from as polysaccharide hemicellulose, and their polyuronide has been the chief object of investigation1)-3). In various soil, the polyuronide is found in a large quantity in fulvic fraction of soil organic matter and has been considered as important in connection with the physical structure of soil4),5). According to Lynch 5), the carbohydrate content of humic acid is markedly smaller than that of fulvic acid. His work also indicates that a' considerable change is noted in the content and composition of the carbohydrate in humic acid because of the addition of some organic substances to the soils, or of the cultivation of virgin soils. Further, some investigators7) believe that uronic acid is introduced into the aromatic structure of the humic acid by changing into pentose and furan. Accordingly, it seems that the role of carbohydrate in the formation of soil humic acid should not be overlooked. 相似文献
12.
3,4-Dichloroaniline (DCA), a biodegradation intermediate of numerous herbicides, binds covalently to soil humus to form persistent complexes. Prompted by the possibility that, upon repeated treatments, xenobiotic residues may accumulate in humus, the turnover rates of intact, solvent-extracted, and hydrolyzed humic complexes of 14C-DCA were compared with that of similarly-treated soil organic matter fractions. The turnover rate of intact humic-DCA complexes was considerably faster than the average turnover of soil organic matter. Humic-DCA complexes, that had been washed in solvents to remove adsorbed DCA or hydrolyzed to break susceptible chemical bonds, had turnover rates that were equal to or slower than that of the average soil organic matter, respectively. However, the turnover rates of the solvent-washed and hydrolyzed humic-DCA complexes were similar to that of identically-treated humic acid. The evidence indicates that an extensive accumulation of DCA or similar herbicide-derived halogenated anilines in soil organic matter is unlikely. 相似文献
13.
作物秸秆碳在土壤中分解和转化规律的研究 总被引：12，自引：4，他引：12
采用14C标记秸秆,在大田和实验室的研究结果表明,秸秆的分解速率主要取决于C/N比。施入土壤后,土壤微生物迅速增加,尤其是细菌。秸秆降解首先形成非结构物质,其中大部分转化为富里酸,进而转化为胡敏酸。分解产物对土壤腐殖质的更新,从腐殖质表面官能团或分子断片开始,逐步进行。非结构物质可与腐殖酸的单个分子产生交联作用,在一定条件下,交联的复合分子可进入腐殖质分子核心的成分中。腐殖酸单个组分在土壤中的转化和重新分配,仅仅与腐殖质表面官能团的反交换过程密切相关。粘土矿物选择性吸附胡敏酸,而且优先吸附胡敏酸中低分子成分。 相似文献
14.
15.
The effect of liming on organic matter in sandy loamy soddy-podzolic soil was studied. The study was performed on samples
taken from the 50-year-long experiment established by Prof. Kornilov in 1957. It was shown that liming had almost no effect
on the total humus content in the soil. The humus composition was studied using two fractionation methods of the humus substances
by the Ponomareva-Plotnikova procedure. The regrouping of the humus fractions occurred due to the changes in the mobility
of soil mineral components, which involved a regular increase in the content of the Ca-bound fraction of humic acids (HA-2)
at the expense of the HA-1 fraction bound to the mobile forms of R2O3 reliable at the lime rates equivalent to the total acidity and higher. The levels of the stabilization of the different HA
fractions were considered, as well as the stability of the changes in the humus composition during 50 years. 相似文献
16.
Calcium-bound and iron- and aluminium-bound humus extracted from different soils collected from north to south of China were characterized by chemical and spectroscopic methods. Meaningful differences in the composition and structure between them were revealed by 13C NMR, visible spectroscopy and elemental analysis. Results showed that the contents of carbon, hydrogen and nitrogen were higher in iron- and aluminium-bound humus than in calcium-bound humus while oxygen content in calcium-bound humus was shown to be higher. The calcium-bound humus had higher C/N and O/C ratios than iron- and aluminium-bound humus. The calcium-bound humic acid (HA1) showed higher E4/E6 ratios than iron- and aluminum-bound humic acid (HA2) while iron- and aluminum-bound fulvic acid (FA2) showed higher E4/E6 ratios than calcium-bound fulvic acid (FA1). An inverse relationship between E4/E6 ratios and aromaticity as determined by 13C NMR spectra was observed for HA and FA from black soil. The 13C NMR spectroscopy revealed that HA2 was more aromatic than HA1. On the other hand, FA1 exhibited a higher aromaticity than FA2. 相似文献
17.
Stability of humus in the plow layer soil is considered to affect the quantity and quality of dissolved organic matter leached from the plow layer soil. Therefore, a model experiment was conducted to analyze the effect of soil reduction under submerged conditions on the stability of humus in the plow layer soil. The changes in the stability of humus in the plow layer soil during submerged incubations with and without rice straw application were evaluated based on the changes in the binding type of humus. Binding type of humus in the plow layer soil was analyzed by successive extractions of organic matter with water, 0.25 M Na2SO4, 0.1 M Na4P2O7 (pH 7.0), 0.1 M Na4P2O7 (pH 10.5), and 0.1 M Na4P2O7 (pH 10.5) with NaBH4. Amounts of Fe, Mn, and Mg in each fraction were also determined to estimate the relationships between humus and metals. The successive extraction of humus indicated that the amount of organic carbon which was extractable with the (NaBH4 +0.1 M Na4P2O7) solution decreased while that of the 0.1 M Na4P2O7 (pH 7.0}-extractable organic carbon increased during submerged incubation with rice straw application. The origin of the increase in the amount of organic carbon in the Na4P2O7 (pH 7.0)-extractable fraction during submerged incubation was investigated further by another incubation experiment using 13C-glucose as a reducing agent. Atom- 13C% analysis showed that the contribution of organic carbon derived from compounds other than glucose to the increase in the contents of humic acids and fulvic acids in the Na4P2O7 (pH 7.0)-extractable fractions was ca. 80%. Therefore, it was concluded that the binding type of humus changed from (NaBH4 + Na4P2O7)-extractable to Na4P2O7 (pH 7.0)-extractable humus under reducing conditions. Since the amounts of organic carbon and Fe increased in the Na4P2O7 (pH 7.0)-extractable fraction and decreased in the (NaBH4 +0.1 M Na4P2O7)-extractable fraction simultaneously, iron reduction was presumably associated with the change in the binding type of humus in submerged paddy soil. 相似文献
18.
Ion exchange equilibriums in a complex of brown humic acids (HAs) and related fulvic acids (FAs) with cations (H+, K+, Na+, Ca2+, Mg2+, Zn2+, Mn2+, Cu2+, Fe3+, and Al3+) have been studied, and the activity coefficients of the acid monoionic forms have been determined. The composition of the stoichiometric cell in the system of black and brown HAs and related FAs in a leached chernozem of the Ob’ region has been calculated with consideration for the earlier studies of the ion exchange properties of black HAs and related FAs. It has been shown that hydrogen, calcium, magnesium, aluminum, and iron are the major components in the exchange complex of humus acids in the leached chernozem with the other cations being of subordinate importance. In spite of some differences between the analytical and calculated compositions of the humus acids, the results of the calculations can be considered satisfactory. They indicate that calculations are feasible for such complex objects as soils, and their accuracy will improve with the expansion of the experimental studies. The physicochemical simulation of the transformation of the humus acid composition under different acid-base conditions shows that the contents of most cations decrease under alkalization, and hydroxides or carbonates become the most stable forms of these cations. Under the acidification of solutions, the binding of alkaline and alkaline-earth elements by humus acids decreases and the adsorption of iron and aluminum by humus acids increases. 相似文献
19.
Chemical and optical characteristics of soil humus have been analyzed as “memory” components of the Pleistocene volcanic paleosols in Mexico. We have studied the A1 horizons of buried Andosols of the Nevado de Toluca series and of the modern Andosols formed under different bioclimatic conditions. Data on the organic matter of buried paleosols suggest that Andosols of the Nevado de Toluca series were formed in humid forest ecosystems. Optical characteristics of the humic acids and data on the molecular-mass distribution of the humus make it possible to assume that these soils were formed under pine forests rather than under fir forests. 相似文献
20.
Soil organic matter accumulation, litter decomposition and humus forms under mediterranean-type forests in southern Tuscany, Italy 总被引：1，自引：0，他引：1
The amount of organic matter and rate of litter decomposition in relation to vegetation type under mediterranean-type forests in southern Tuscany was studied. Since existing concepts are largely based on studies of soils on calcareous substrates in this region, particular attention was paid to soils on non-calcareous materials. The humus type and distribution at five sites on acid metamorphic rocks and at one site on dolomitic limestone with different vegetation types was investigated. The input of above-ground litter was also determined. On the metamorphic rocks, clear trends in humus profile development could be observed from deciduous through sclerophyllous to coniferous vegetation: there was a decrease in litter nitrogen content (9.3 to 5.8 g N kg?1 DM), an increase in the amount of organic matter in ectorganic layers (2.53 to 4.66 kg m?2), a decrease in the decay constant k (0.26 ± 0.02 to 0.17 ± 0.03 a?1), and a decrease in soil faunal activity. The results indicate that, under eu-mediterranean to sub-mediterranean forests, decomposition rates are comparable to those under temperate deciduous forests, and that the dominant humus form is a leptomoder. The spatial variation in the amount of organic matter within the plots was considerable, and was related to vegetation type. 相似文献