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1.
G. N. Fedotov E. I. Pakhomov A. I. Pozdnyakov A. I. Kuklin A. Kh. Islamov V. I. Putlyaev 《Eurasian Soil Science》2007,40(9):956-961
Changes in the fractal dimension and scattering intensity of colloidal structures in a chernozem, soddy-podzolic soil, and a krasnozem were studied by small-angle neutron scattering at different temperatures and soil water contents. The character of the neutron scattering by soil colloids indicated that the latter were mass fractals in all of the soils studied; i.e., the colloidal particles were located apart from one another even in dry soils. The obtained results confirmed the supposition about the distribution of colloidal particles in the humus gel matrix. The changes in the fractal parameters of the soddy-podzolic soil and chernozem with increasing water contents were nonmonotonic in character, which indicated complex structural rearrangements of the colloidal component in these soils. From the results obtained, a conclusion was drawn that the destruction of the molecular network of reinforced humus gel occurred upon heating the soils to high temperatures: colloidal particles reinforcing the humus gel began to move and coagulate with the formation of dense aggregates. The electron-microscopic study of gel films released from the predried and then capillary wetted aggregates in water showed that the gel films were nonhomogeneous and included zones of humus gel reinforced by colloidal particles and zones almost free from these particles. 相似文献
2.
G. N. Fedotov G. V. Dobrovol’skii V. I. Putlyaev E. I. Pakhomov A. I. Kuklin A. Kh. Islamov 《Eurasian Soil Science》2007,40(7):740-746
An electron-microscopic study was conducted of gel films collected from aggregates from humus-accumulative horizons of chernozem and soddy-podzolic soils. The aggregates were dried and then capillary-wetted and immersed in water, Solutions obtained by pressing from these soils were also studied. Based on the results obtained, a hypothetical mechanism was proposed for the development of fractal organization of soil colloids, which involves the fixation of micron-size mineral particles in the humus gel and their transformation under the effect of aggressive substances with the formation of colloidal particles of reaction products diffusing in the humus gel. Humus macromolecules contain many polar groups; therefore, the colloidal particles pass some distance and are then fixed on these groups. The greater the distance from a coarse particle in the center of a cluster the smaller the number of colloidal particles capable of traversing it. Therefore, the concentration of colloidal particles decreases when going from the cluster center to its periphery according to an exponential law, which results in the development of the fractal organization in the colloidal soil component. Results of soil studies using the small-angle neutron scattering method were analyzed in terms of the hypothesis proposed. 相似文献
3.
Hidenori Hashimoto Togoro Harada Toshinobu Yumoto 《Soil Science and Plant Nutrition》2013,59(3):110-116
In the preceding paper (1) the authors reported the humus status in the organo-mineral colloidal complexes of the degraded paddy soils, which is characterized by the leaching of active iron, manganese and the other elements such as silica, magnesium and phosphoric acid from the furrow slice (2). And it was concluded that the organo-mineral colloidal complexes (Gl colloidal complexes) of the degraded paddy soil is characterized by the marked accumulation of humus, especially the readily soluble humus as compared with those of the normal. 相似文献
4.
Arguments are presented for changing the approach to soil studies in order to consider the behavior of soils in terms of a colloid-chemical model rather than in terms of a physical model. Experimental studies of changes in the stickiness of an air-dry chernozem depending on the time elapsed since adding water, of the catalase activity of soils depending on the time elapsed since adding water and salt solutions, of the thermal diffusivity of soils depending on the time elapsed since adding water, and of the soil temperature showed that the soil solution is a structured colloidal system. Electron microscopic studies of soil solutions confirmed that colloidal particles of soil solutions interact with one another due to long-range aggregation to form periodic colloidal structures enclosing soil moisture. It was concluded that the colloidal structuring of the soil solution makes it similar to physiological fluids and makes the soils similar to biological systems; therefore, the consideration of soils in terms of a colloid-chemical model expands our knowledge of these systems and can be useful for soil scientists. 相似文献
5.
有机质对三峡库区水体中土壤胶体颗粒凝聚影响机制研究 总被引：2，自引：0，他引：2
采用联合测定法和光散射技术分别研究了有机质对土壤颗粒表面电荷性质和水体中胶体颗粒凝聚过程的影响。结果表明:添加有机质能显著改变土壤表面电荷性质,使得土壤颗粒表面电荷数量降低6.8%,比表面积增加12.3%,使颗粒表面电荷密度减小,表面电位降低;进一步理论计算表明添加有机质降低了胶体颗粒间的静电排斥力,使得净引力增大,胶体颗粒更易发生凝聚。通过动态光散射分析水体中土壤胶体颗粒的凝聚特征,发现有机质去除前后的临界聚沉浓度(CCC)分别为91.6 mmol/L和139.3mmol/L,去除有机质土壤显著大于未去除有机质的土壤,相应浓度下的临界电位值计算结果均为-150mV左右,与颗粒间出现净引力的临界浓度值基本一致。有机质对水体中胶体颗粒凝聚特性的影响主要是通过改变颗粒表面性质使得颗粒间的相互作用发生变化而引起。 相似文献
6.
黑土肥力变化特点及其与土壤复合胶体性质的关系 总被引：7，自引：3，他引：7
黑土占黑龙江省耕地面积一半以上,是肥沃的土壤.但是,开垦后用养结合不好,土壤肥力呈现明显下降的趋势.本文拟从研究黑土肥力下降及其与土壤复合胶体的关系,以及有机质培肥黑土的效果及其对土壤复合胶体的影响,探索黑土肥力下降原因及培育高产黑土的技术途径,以便为快速培育高产黑土提供科学依据.为此,我们采集不同开垦年限的黑土和施用有机质不同程度培肥的黑土,进行了比较研究. 相似文献
7.
不同植被恢复模式下煤矸石充填复垦土壤物理性质与有机无机复合体的关系 总被引：1，自引：3，他引：1
[目的]揭示复垦土壤物理性质与有机无机复合体的关系,为改善复垦土壤的物理特性提供依据。[方法]选择淮南大通煤矸石充填复垦区三种典型植被恢复模式下人工恢复7a的土壤,定量分析其物理性质及有机无机复合体,并运用多元统计分析两者的关系。[结果]研究区土壤的有机无机复合状况及结合态腐殖质在不同植被恢复下发生了不同程度的变化。结合态腐殖质以稳结态为主,所占比例为41%~67%。植被恢复降低了复垦土壤的容重而增加了其总孔隙度,而且臭椿+草本恢复模式效果最佳。土壤非毛管孔隙度与有机无机复合量及紧结态/重组碳呈显著正相关,而与稳结态/重组碳呈显著负相关。毛管孔隙度与有机无机复合量及紧结态/重组碳呈显著负相关,而与稳结态/重组碳呈显著正相关。土壤总孔隙度及容重与结合态腐殖质各组分的绝对含量分别呈显著正相关和负相关关系。[结论]复垦土壤物理性质与有机无机复合体具有密切关系。 相似文献
8.
草木栖、麦秸和泥炭在黑土中腐解特点及对土壤肥力的影响 总被引：1，自引：0，他引：1
有机物料田间腐解试验表明,各地均以草木栖分解最快,麦秸次之,泥炭最慢;同一有机物料的分解速率,北部克山均比南部哈尔滨慢。腐殖化系数,各地均以泥炭最大,麦秸次之,草木栖最小;同一有机物料的腐殖化系数,北部克山均比南部哈尔滨大。三种有机物料处理黑土:1.提高了腐殖质的数量和品质,增加了养分贮量和保肥能力,泥炭处理优于其他处理。2.明显地提高了胶体复合有机炭和追加复合度,草木栖处理最好,麦秸次之,再次是泥炭。3.改善了胶体腐殖质结合形态,松结态显著增加,土壤腐殖质更加活化,复合胶体的特性也均得到了改善。 相似文献
9.
张夫道 《植物营养与肥料学报》1995,1(3):10-21
长期施用有机肥和化肥,对土壤腐殖质积累和改善品质的作用研究,于1986～1991在俄罗斯季米里亚捷夫农学院等地进行。主要结果如下:.1.有机肥对土壤腐殖质的积累作用大于NPK化肥。施肥所增加的土壤腐殖质,除了砂壤土外,主要是在0～60cm土层,60cm以下土层施肥效果不明显。.2.长期施用有机肥和NPK化肥,提高了胡敏酸组分Ⅰ(游离的及与活性R2O3结合态)的含量和腐殖酸相对迁移率,而与Ca++离子结合的胡敏酸组分Ⅱ含量下降。由于胡敏酸组分Ⅱ与Ca++离子结合减弱,增加了腐殖质在水中的溶解,使之在大雨或大量灌水时易于淋失。.3.施用有机肥和NPK化肥,水溶性腐殖物质的含量明显提高,缓解了干旱条件下土壤高浓度矿物盐的影响。.4.长期施肥提高了土壤的亲水性;其膨胀容积、膨胀速度常数、土壤吸水量、土壤表面积等指标均不同程度的提高,但砂壤土增加了幅度低于粉砂壤土和粘壤土。.5.胡敏酸甲氧基功能团的含量多寡是衡量土壤腐殖质化的重要指标。试验表明,长期施肥下低肥力酸性土壤中胡敏酸甲氧基含量提高了46％～300％,高肥力非酸性土壤提高了17％～32％。 相似文献
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11.
Changes in the content, reserves, and composition of humus in a sandy gleyic iron-humus-illuvial soddy-podzolic soil under intensive, decreasing, and ceased agrotechnical impacts were studied. It was shown that when a well-cultivated soil is removed from economic use, the conditions of humus formation in the former homogeneous plow layer develop differently. A deterioration of the humus status parameters of the layland soil was found as compared to the cultivated soil. It was concluded that, when a soil is removed from economic use, its profile, which was disturbed by the anthropogenic impact, tends to return to the original genetic state. The change in the level of the agricultural practices affected the optical density of the humic acids only slightly, which is indicative of their relative stability under specific soil-forming conditions. 相似文献
12.
胶体颗粒是土壤团聚体及土壤结构形成的基础物质,其表面性质及颗粒间相互作用对土壤性质及其肥力作用有着深刻的影响。原子力显微镜（AFM）具有纳米级的分辨率且能够测量物质颗粒间相互作用力的大小,将其应用于土壤胶体研究,可以更加直观、深入地阐明土壤胶体特性、探索土壤胶体作用机理。本文在概要介绍 AFM 的工作原理和特性的基础上,深入探讨了AFM 在测定土壤胶体表面形貌、测定土壤胶体相互作用力方面的研究进展,并对该领域未来的发展进行展望,可为深入揭示土壤胶体颗粒的表面特征及颗粒间相互作用方式、强度和机制,阐明土壤肥力演变过程、污染物在土壤中的迁移机理提供理论参考。 相似文献
13.
运用野外调查与室内实验分析相结合的方法,利用SPSS 13.0软件和ArcGis 9.3软件对原始红松林、白桦红松混交林Ⅰ(红松天然更新)、白桦红松混交林Ⅱ(红松人工造林)和红松人工纯林4种经营类型红松林下土壤腐殖质进行经典的统计描述和地统计学的空间异质性分析。结果表明:经营类型不同导致土壤腐殖质含量的差异,白桦红松混交林下土壤腐殖质含量高于红松人工纯林。不同经营方式红松林下土壤腐殖质的空间异质性特征显著不同,4种经营类型红松林下土壤腐殖质空间异质性多受随机因素的影响,但2种白桦红松混交林下土壤腐殖质空间异质性的空间自相关部分大于红松人工纯林,而且2种白桦红松混交林下土壤腐殖质空间异质性的尺度也较红松人工纯林下土壤腐殖质空间异质性的尺度大。2种白桦红松混交林林下土壤腐殖质空间分布格局要明显优于红松人工纯林下的土壤腐殖质空间分布格局。研究结果可为红松林的恢复与持续经营提供理论基础。 相似文献
14.
红壤复合胶体腐殖质的特性 总被引：3，自引：0，他引：3
对闽北6个样品测定结果表明,红壤复合胶体中C、N含量较高,其腐殖质的C/N和HA/FA、胡敏酸的芳构化度和腐殖质氧化稳定性系数均较重组小,而松结合态/紧结合态腐殖质的比值则较大.这些特性有利于土壤养分保存与供应和改善土壤结构. 相似文献
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Hidenori Hashimoto Togoro Harada Toshinobu Yumoto 《Soil Science and Plant Nutrition》2013,59(3):114-119
In the preceding paper (1), humus status in G 1 colloidal complexes of the high yield paddy soils was reported. This report describes the experimental results on the clay minerals contained in G 1 colloidal complexes of the same soils as above. 相似文献
17.
M. F. Ovchinnikova 《Moscow University Soil Science Bulletin》2009,64(1):10-16
The transformation of humic substances in soddy-podzolic soils under agrogenic impacts of different intensities and durations was studied. Indices of the initial stages of degradation and regradation of soil humus were revealed, and the humus status of soils under different fertilizing conditions was estimated. 相似文献
18.
We studied the physical properties of chernozems subjected to local waterlogging because of different reasons. The secondary soil hydromorphism resulted in insignificant changes in the soil’s texture related to some redistribution of the elementary soil particles by the particle-size fractions. The physical clay content somewhat increased in the lower part of the soil profiles (in the B2 and BC horizons) at the expense of the clay particles. The bulk density of the waterlogged soils somewhat increased, particularly in the B2 horizon. The regular soil waterlogging worsened the soil’s structural status with a decrease in the content of the silt-size aggregates and an increase in the content of the coarse blocky aggregates. The changes in the soil’s structure can be considered a diagnostic feature of the locally waterlogged chernozems. The water stability of the aggregates increased due to the higher contents of the major cementing agents, including the soil humus and carbonates. 相似文献
19.
The composition of humus in leached chernozems differs from that in gleyed podzolized chernozem-like soils in the northern forest-steppe zone of European Russia. Leached chernozems have the fulvate-humate humus. Gleyed podzolized chernozem-like soils have the humate-fulvate humus. A more aggressive composition of humus in the latter soils is caused by their overwetting and the development of gley processes under conditions of a stagnant-percolative soil water regime. 相似文献
20.
In three West Siberian geomorphological regions, the snowpack was measured and the soil frost depth, the volume of surface runoff, the humus content of the soil, and the chemical composition of meltwater were determined for each year from 1969 to 2007. The study was carried out on chernozem-type soils during different hydrological years. The water content of the snow varied in those years from 65 mm under low-snow conditions to 255 mm in very snowy winters. Both the amount of snow and the type of land use influence the surface runoff volume. Slopes covered with perennial grasses and plowland had the greatest snowmelt runoff values (> 50% of the water content of snow). The removal of clay particles depletes the humus from chernozem and phaeozem soils. Moderately eroded soil is transformed into medium-humus soil, and strong erosion leads to low-humus soil. In meltwater running on the surface of phaeozems situated near a cement factory, the concentrations of calcium and magnesium were 15- to 20-fold higher and carbon concentrations were 1.5-fold higher than in soils outside the pollution zone. 相似文献