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1.
E. A. Niederbudde 《植物养料与土壤学杂志》1976,139(1):57-71
Transformation of three-layer silicates through K-release and K-uptake (A review). In soils formed from unconsilidated sediments with illite-vermiculite-smectite mixtures in their clay fractions the clay mineral transformation from illite to vermiculite and smectite between pH 5 and 7 cannot be considered so far as proven on the grounds of available analytical data. Studies of soil profiles showed that the formation of illite from expandable three layer silicates predominates over the formation of smectite from illite. Practically all samples of loess and calcareous tills of the areas discussed contain smectites. K loesses between pH 5 and 7 are probably very small, because K released during the formation of vermiculites from micas is immediately fixed by smectitic layers which are converted to illite. In those soils potential K fixation of the clay fraction (« 2 μ) is lower than in the corresponding parent sediments despite of vermiculite formation in the soils. Further analytical data (X-ray, interlattice-K, K-selectivity, specific surface) support the hypothesis of illitization of smectites during soil formation. 相似文献
2.
Laurent Caner Emmanuel Joussein Sébastien Salvador‐Blanes Fabien Hubert Jean‐Frédéric Schlicht Nelly Duigou 《植物养料与土壤学杂志》2010,173(4):591-600
Major weathering sequences in soils are well established; however, knowledge on rates of mineral transformations remains unknown, because it is often difficult to date precisely soil processes. This work was carried out on soils developed on recent (< 188 y) sand dunes on the W coast of Oléron Island (France). The coast has been protected against marine and wind erosion by constructing five consecutives barriers close to the coastline since 1820 (1820, 1864, 1876, 1889, 1948) defining the maximum age of the soil parent material, as before the areas between the barriers were under water. Soils on the older dunes have low clay content (> 94% of sand) and exhibit a bleached E horizon that overlies a yellowish brown B horizon. The process responsible for their formation is podzolization promoted by the high permeability of the material and complexing organic matter produced by coniferous vegetation. Initial mineralogy of C horizons is homogenous and constituted of chlorite, illite, illite/smectite mixed‐layer minerals, and kaolinite, quartz, calcite (≈ 8% related to shell fragments), and feldspars. The initial clay‐mineral assemblage of the E horizons is dominated by illite (well‐crystallized WCI and poorly crystallized PCI) and chlorite. With progressive podzolization, poorly crystallized illite is first transformed to illite/smectite mixed‐layer minerals and in a further step into smectite. In addition, transformation of well‐crystallized illite leads to formation of ordered illite/smectite mixed‐layer minerals in the E horizons, which is not commonly described in soils. In the B horizons, illite/smectite mixed‐layer minerals are present with traces of smectite, as well as Al and Fe oxi‐hydroxides as revealed by DCB and oxalate chemical extractions. This chronosequence illustrates that over short distances and short time (< 188 y) intense mineral weathering and soil development occur. Major clay‐mineral changes occur between 132 and 188 y in agreement with development of the pine forest producing acidic litter. 相似文献
3.
We investigated the processes of mineral formation in three Alfisol profiles of Sierra Nevada (southern Spain), with special emphasis on the little-studied process of mica inheritance, particularly as regards its quantitative aspects. X-ray diffraction, conventional and high resolution transmission electron microscopy, selected-area electron diffraction, and geochemical analysis of the soil solution were used, and the granulometric fractions gravel, coarse sand, fine sand, silt and clay were studied, as was unaltered parent rock. Most interesting was inheritance of dioctahedral mica (illites) with small crystallochemical changes. The transition of mica from parent rock to clay was characterized by small crystallochemical changes affecting their structural formulae, reduction of the 2M1 polytype content, decrease in crystallite size, increase in crystal defects, and other changes in particle morphology. We propose the term 'pedocrystallochemical evolution' for the transition. The changes reverse the processes that take place in micas when rocks are formed by sedimentation, diagenesis and metamorphism. The kaolinite in the soils is a result of neoformation, and acts as the equilibrium phase within the chemical system. Reddening seems to have been caused by both inheritance and neoformation of iron oxides (haematite + goethite). 相似文献
4.
北京香山地区褐土粘土矿物的研究 总被引：1，自引：0，他引：1
我国褐土作为一个独立的发生学土类是1958年以后被确定了的(Герасимов1958)。在这前后,李连捷、华孟、文振旺、许冀泉等都曾从不同角度、对褐土分布地区的土壤进行调查研究,得出一些有意义的结论1-2)(文振旺等,1959;中国科学院土壤及水土保持研究所等,1961;许冀泉,1961)。而对褐土中粘土矿物的研究,许冀泉的工作,是极其有益的。本文报告的是作者1961-1964年对北京香山地区褐土粘土矿物进行研究的结果。 相似文献
5.
Permafrost desiccates and indurates soil horizons. During summer, the perennially frozen ground under the active thawed layer creates confined conditions, Whereas in winter the closed system between the permafrost and the freezing front migrating downwards leads to irreversible changes in the soil structure and to transformation and neoformation of minerals. Two examples were studied by field observation and laboratory analyses (optical microscopy, scanning electron microscopy, X-ray diffractometry, transmission electron microscopy and analytical electron microscopy). In Transbaikalia (southeastern Siberia) a Pleistocene cryogenic slope deposit on syenite contains detrital clays (chlorite, illite), but neoformed ferroan smectites dominate. In Patagonia, centimetre-sized silica concretions containing spongy and spheroidal opal occur in alluvium ascribed to cold Pleistocene periods. They seem to have formed from primary detrital smectite that was transformed to fibrous clay (sepiolite) then to acicular opal, and eventually to spheroidal opal. The neoformed opal contains 27% magnesium. These features occur systematically within fossil cryoturbations not related to present conditions. It appears that clay transformation and neoformation can happen at temperatures far lower than 0°C. 相似文献
6.
Balances of alteration and migration of clay fractions and clay minerals in Gray Brown Podzolic Soils from Loess Balances of alteration and migration of clay fractions, clay minerals, K, Mg and Fe bound in clay silicates were calculated for Gray Brown Podzolic Soils (Parabraunerden) derived from Young Pleistocene Loess below arable and forest land in the district south of Würzburg. The extent of clay formation lies between 63 and 98 kg/m2, of which 60–80 % belong to the fraction <0.1 μm. The clay migration varies between 35 and 51 kg/m2, the fractions < 0.2 μm (especially the fraction <0.1 μm) predominating, the coarse clay being involved only to a smaller extent. During Holocene soil formation 121 kg illite, 16 kg vermiculite and 11 kg kaolinite per m2 are formed in the clay fraction (< 2 pm). The loss of smectite amounts to 68 kg/m2. The biggest alterations of the clay mineral quantities occur in the fraction <0.1 pm; they indicate a smectite-illite transformation. Illite, at 23 kg/m2, accounts for half of the clay migration, followed by smectite and vermiculite each at 9 kg/m2 and kaolinite at 5 kg/m2. When comparing the migrated with the present amounts no preference of certain clay minerals during clay migration can be determined. In the clay fractions the gained Fe (3.07?4.32 kg/m2) and K (2.75?3.84 kg/m2) predominate over Mg (0.57?1.15 kg/m2). The three elements accumulate to the greatest extent in the fine clay fraction. The element migration parallels the gain. The balances of the elements are discussed in connection with pedogenic illite formation as well as biotite and vermiculite disintegration. 相似文献
7.
The mineralogy of four Italian Andosols - derived from volcanic material either oversaturated or undersaturated with respect to silica - has been investigated by XRD, EM and IR. The crystalline clay minerals in all four profiles are essentially similar, consisting of abundant halloysite with moderate illite and 14A intergrade material, minor kaolinite and occasional gibbsite. The soils also contain large amounts of imogolite and proto-imogolite allophane. With the exception of illite all these clay minerals are believed to be of pedogenic origin. Halloysite occurs in the dehydrated form in the surface horizons but becomes progressively more hydrated with depth. At depths of > 1.4 m the clay fraction consists almost entirely of fully hydrated halloysite, supporting the suggestion that halloysite forms best in a stagnant moisture regime where there is a depositional overburden acting as a silica source. EM observations show that the halloysite may have spherical morphology and may be intimately associated with gas vesicles in pumice grains where it probably forms by the transformation of allophanic material. It seems likely that dehydrated halloysite slowly converts to poorly crystallized kaolinite in the upper horizons of these profiles. The origin of the 2/1 minerals is more problematical. Illite is probably inherited from mica in the parent material but the 14A intergrade material is so poorly ordered that a pedogenic origin seems more likely than formation by inheritance or by transformation of pre-existing 2/1 silicates. 相似文献
8.
Zhang Zhi Yi Huang Li Liu Fan Wang Ming Kuang Ndzana Georges Martial Liu Zhi Jie 《Journal of Soils and Sediments》2019,19(1):211-220
Purpose
Clay minerals significantly affect the physical, chemical, and biological processes of soils. They undergo spontaneous modification and transformation depending to the climatic conditions. Information concerning the compositions and transformation of clay minerals in nanoparticle colloids (NPs) (25–100 nm) is severely lacking. Studying clay mineral transformation is important approach to understand soil formation. This study was conducted to determine the transformation sequence of clay minerals in several zonal soil NPs.
Materials and methodsFour soils (Haplustalf, Alf-1; Hapludalf, Alf-2; Hapludults, Ult-1 and Ult-2) were collected from B horizons developed under three different climatic zones of China. Alf-1 (36° 05′ N and 117° 24′ E) was located under a warm temperate zone and Alf-2 (30° 38′ N and 115° 26′ E), Ult-1 (29° 13′ N and 113° 46′ E), and Ult-2 (19° 27′ N and 109° 17′ E) under a subtropical zone. The clay particles (<?2000 nm) (CPs) and nanoparticles (25–100 nm) (NPs) of tested soils were separated. The element composition of CPs and NPs was identified by microwave digestion method. The mineralogy and chemical bonding of clay minerals were studied by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR).
Results and discussionWith decreasing latitude, NPs and CPs showed that the molar ratio of SiO2 to Al2O3 trends to diminish, indicating the phenomenon of desilication and allitization in the tested soils. XRD analysis revealed that the main clay mineral of Alf-1 NPs was illite, followed by vermiculite, kaolinite, and kaolinite interstratified minerals (KIMs). The clay minerals of Alf-2, Ult-1, and Ult-2 NPs were dominated by kaolinite (and KIMs), followed by illite, with a little content of hydroxyl-interlayered vermiculite (HIV) in Ult-1 NPs and trace content of gibbsite in Ult-2 NPs. With decreasing latitude, vermiculite and HIV decreased in NPs. When compared to CPs, smectite as well as illite-vermiculite mix-layer mineral (I-V) and illite-HIV mix-layer mineral (I-HIV) were not detected in NPs. The analysis of d060 region by XRD showed that with decreasing latitude, the main clay minerals in NPs were dioctahedral minerals (e.g., illite or kaolinite). These clay minerals resulted from the transformation of trioctahedral minerals in CPs. The disappearance of 2:1 swelling minerals and trioctahedral minerals showed that the NPs were more susceptible to weathering than CPs.
ConclusionsWith decreasing latitude, the transformation of clay minerals followed the sequence of illite?→?HIV?→?kaolinite?→?gibbsite in tested NPs.
相似文献9.
Tepetates are common in the Mexican highlands, and are classified as fragipan, duripan, pedosediments or saprolite. A common feature is the abundance of clay coatings. Three pedons with red tepetate and grey tepetate were selected at different altitudes and slopes in a small watershed in Texcoco, Mexico. Physical, chemical, mineralogical and micromorphological analyses were carried out in soil, tepetate and separated clay coatings. Clay illuviation and neoformation indexes were calculated using micromorphometric techniques. Red tepetate is composed of basic volcanic glass dust (andesitic vitric tuff), and has a high clay neoformation and illuviation index. In contrast, grey tepetate is composed of acid volcanic glass (acid vitric tuff) and only clay neoformation takes place, leading to the formation of a clayey soil. Although all the tepetates were subject to pedogenesis, the intensity and variation of the processes increases on the lower slope and different diagnostic horizons are formed, due to tepetate erosion. The laterally running waters containing suspensions of particles and soluble silica were deposited or precipitated in sediments or tepetates on the lower slopes, giving rise to compound coatings. These processes must be older than 20,000 years. Tepetates from Texcoco present several variants which were recognised since pre-Hispanic times. 相似文献
10.
This paper presents the results of a study of clay mineralogy and Pb, Zn, Cu, Rb, Sr, Y and Zr analyses of soils and stream sediments of the Schwarzach watershed, a drainage system located in a secluded rural region of eastern Bavaria, far removed from major industrial installations.Clay fractions of soils and stream sediments differ significantly in their mineralogy. The soils average 50% secondary chlorite and 40% illite, whereas recent stream sediments average 20% chlorite and 70% illite. These assemblages are possibly interconvertible under the influence, or on withdrawal, of Schwarzach water. Proportions of clay minerals in fossil stream sediments average approximately 30% chlorite, 50% illite, and 20% kaolinite with up to 10% of 10–14 Å interstratified minerals.Surface soil layers have been enriched in Pb, as have recent stream sediments. The latter have also been enriched in Zn and Cu. The increased amounts of Pb plus its close association with organic C indicate atmospheric deposition of Pb and incipient eutrophication of the Schwarzach River. 相似文献
11.
Since three decades ago it has been established by numerous investigators4,7,9) that the general Process of formation of clay minerals is different between the marine and terrestrial conditions, and that the clays of the marine origin are, in general, of illitic type, whereas those of the terrestrial are of kaolin group. In previous communications,1,2) it was reported that clay fractions of the soil and mud from the Ariake Sea are characterized by the abundance of minerals of illite-montmorin series (montmorin refers to montmorillonite group after Jackson and Sherman8), being different from most terrestrial soils in Kyushu. The matter seems to be of some importance because the Presence of montmorin, even in a relatively small quantity, is likely to exercise a considerable, influence on the behaviour and properties of the clay and the fertility of the soil. The soils of the reclaimed land of the Sea are not only productive, Whether they are clayey or sandy, but also they have been approved to be powerful improving materials for the degraded paddy soils, so-called “Akiochi” soils by several field experiments. 相似文献
12.
根据在电白大放鸡渔场开展人工鱼礁投放海域本底调查所获的海洋资源和环境资料及以往有关文献中对该海域的调查资料,对人工鱼礁礁区的生物资源、海水水质、底质等方面进行评价,认为电白大放鸡渔场人工鱼礁礁区滨海旅游基础好,海洋渔业资源种类繁多,浮游生物丰富,水质良好,底质多为沙、粗沙或粉沙黏土为主,具有营造游钓鱼礁,发展海洋（岛）生态旅游与娱乐游钓的得天独厚的自然条件. 相似文献
13.
在亚热带丘陵河谷地小流域范围内地表物质的迁移常可导致不同沉积区物质组成的变化 .从黄泥土→洪积泥砂土→培泥砂土 ,随着搬运距离的增加 ,其粘粒矿物组成发生了一系列的变化 ;高岭石逐渐下降 ,云母逐渐增加 ,蛭石渐趋下降消失 ,而绿泥石则逐渐形成 ;同时赤铁矿、针铁矿也先后下降消失 .矿物的演化与沉积物所处环境的水分条件及溶液中盐基物质和酸碱度变化有关 相似文献
14.
N. V. Kozlova L. S. Malyukova T. A. Sokolova T. Ya. Dronova 《Moscow University Soil Science Bulletin》2008,63(4):154-159
Swelling minerals of the montmorillonite group predominate in the clay fraction of acid brown forest soils under tea plantations; illite and quartz are present in smaller amounts; small amounts of chlorite-like structures are also found. A decrease in the content of swelling mineral and a deterioration of their crystallization degree (especially in the upper horizons) take place upon the long-term application of mineral fertilizers at high rates; also, the accumulation of illite takes place. These processes attest to the beginning of degradation and/or removal of montmorillonite minerals (the most finely dispersed and hydrophilic clay minerals) under the impact of a significant decrease in pH because of the high rates of physiologically acid fertilizers in combination with illitization under the impact of potassium application. 相似文献
15.
南京地区水稻土中固定态铵与伊利石的相关性 总被引：1，自引：0，他引：1
本文以南京地区长城岗和泉水两个水稻土剖面为研究对象,在利用Silva-Bremner法测定土壤全样和3个粒级(黏粒、粉粒和细砂粒)的固定态铵含量、利用X-射线衍射仪测定矿物成分的基础上,讨论了固定态铵含量与粒级以及矿物种类的关系.结果认为,两个剖面在以下几个方面具有共性:①在黏粒、粉粒和细砂粒3个粒级中,黏粘粒含量与固定态铵含量的关系最为密切,相关系数分别为0.68和0.64;②在黏粒中的伊利石、高岭石和蒙脱石3种主要矿物中,伊利石含量与固定态铵含量相关性最好,相关系数分别为0.50和0.49;⑨对于全样来说,其中的伊利石含量与同定态铵含量呈极显著正相关,相关系数分别为0.68和0.66.这些数据充分说明,伊利石是南京地区水稻土中固定态铵赋存的最主要载体. 相似文献
16.
Morphological and analytical data corresponding to several profiles from two mangrove systems in the Brazilian state of São Paulo were examined for evidence of pedogenetic processes. Plant activity exerted a strong effect on the processes occurring in mangrove substrates, especially on the intensity of these processes and, therefore, constitutes one of the major factors involved in the differentiation of sediments and soils. Colonization of substrates by vascular plants leads to drastic changes in physicochemical conditions. The redox processes were much more diverse in the soil than in the sediment (substrate without vegetation); in the former they varied with depth, with oxic or suboxic conditions being observed at the surface and anoxic conditions observed below 30 cm, whereas in the sediment, anoxic conditions were observed throughout. Likewise, the acid–base conditions were more variable in the soils, ranging from strongly acid to neutral, and in the sediment they were close to neutral. Furthermore, different pedogenetic processes were identified: (1) addition of organic matter by accumulation of vegetable debris and dead roots, with formation – in some cases – of a histic epipedon, (2) transfer of soluble iron (Fe2+) towards the surface and precipitation in the form of Fe oxyhydroxide, and transfer of the mineral particles due to the bioturbation caused by activity of crabs, (3) transformation of elements such as iron (gleization) and sulphur (sulphidization). Changes undergone in the mangrove substrates were also characterized by simultaneity and intergradations between pedogenesis and diagenesis, especially in the lowermost layers in which authigenesis appears to intensify. Thus, the presence of smectite minerals in the clay fraction may be attributed to authigenic processes that take place in both soils and sediments. 相似文献
17.
V. R. Ouhadi R. N. Yong H. Bayesteh A. R. Goodarzi 《Water, air, and soil pollution》2007,181(1-4):77-93
Contaminant adsorption properties of clays are markedly influenced by the type of clay minerals, the nature of the exchangeable ions, and the type of clay microstructure present. Clay soils, due to their high buffering capacity and low permeability, are very helpful materials as barriers in waste disposal projects. On the other hand, the different microstructures of clay soils, due to their different surface areas and the different quantity of these surfaces exposed to the water, cause different contaminant attenuation levels for clay minerals. Even though the dispersive structures of soils might cause some geotechnical problems, in geo-environmental projects they might be of use as an excellent contaminant absorbent due to the fact that their clay particles are well-exposed to the soil pore fluid. The present study investigates the role of various types and concentrations of pore fluid on the microstructure and contaminant adsorption of illite. A series of pH measurements, a turbidity experiment, an XRD analysis, batch equilibrium testing and soil adsorption evaluation were performed to achieve the aforementioned objective. Homo-ionic illite mineral was prepared and some experiments were performed on it to support the findings. The results of this study show that although the theoretical calculation of the double layer theory does not take into account the effect of different anion types on the variation of the thickness of double layer, the anion type has a major impact on the microstructure variations of clay minerals. In addition, the turbidity measurement and the monitoring of XRD peak intensity of the major basal spacings of illite are appropriate tools for evaluating its dispersivity behaviour. It is shown that the PDI treated illite has more capacity for adsorption of heavy metal contaminant than that of illite or Ca–illite. It is concluded that the observed geo-environmental behaviour is noticeably a function of changes in the microstructure of illite. 相似文献
18.
Clay mineralogy was determined in a sequence of soils formed in slope deposits derived from Hauptdolomit and ranging from a Mullrendzina (Rendoll) to a Terra fusca (Eutrochrept) and a Parabraunerde-Terra fusca (Hapludalf). Results indicated an alteration of illite to hydroxyl-Al interlayered clay in the course of soil formation. No evidence was found of formation of kaolinite in these soils. This clearly confirms all soils to have been formed under a recent cold humid climate. Furthermore clay mineral weathering starts even before carbonates are dissolved and completely removed from these soils. 相似文献
19.
The role of coarse material (sand fraction) in the distributionof metals in polluted marine sediments was investigated in theharbors and the coastal zone of Mytilene, island of Lesvos,Aegean Sea. It was found that sand fraction contains a relatively significant proportion of the anthropogenic metalsand therefore it cannot be neglected in metal pollution studiesof coastal sediments. Also the distribution of the anthropogenicmetals (Cd, Cu, Pb and Zn) in both silt+clay and sand fractionsfollow the same pattern indicating similar pollution sources. In the bulk sediment (clay + silt + sand fraction) all anthropogenic metals had a significant amount (> 50%) in theacid-extractable (and potentially bio-available) fraction. 相似文献
20.
黏粒矿物影响着土壤理化性质，可指示成土因素特征和土壤发生发育过程/强度，也是中国土壤系统分类的基层单元土族矿物学类型划分的重要依据。本研究选择了广西不同纬度和成土母质的18个代表性水耕人为土的剖面，应用X射线衍射（XRD）方法分析了其典型水耕氧化还原层（Br层）的黏粒矿物组成及其空间分布特征，并确定了其中“黏质”剖面的土族控制层段矿物学类型。结果表明：（1）供试土壤的黏粒矿物主要包括高岭石、伊利石、三水铝石、1.42 nm过渡矿物、蒙脱石和蛭石等，依次分别出现在100%、88.9%、72.2%、61.1%、44.4%和38.9%的剖面中。（2）黏粒矿物组成在纬度空间分布上具有明显规律性特征。随着纬度降低，土壤黏粒中的高岭石增加，伊利石、蒙脱石、1.42nm过渡矿物逐渐减少；纬度＞23°N区域内，成土母质对黏粒矿物组成影响明显。（3）纬度23°N是黏粒矿物组成和土族矿物学类型分界线，＜23°N区域，黏粒矿物均以高岭石为主，是“黏质”剖面的土族控制层段的主要矿物学类型；＞23°N区域，黏粒矿物组成以高岭石、蒙脱石、伊利石或1.42 nm过渡矿物为主，因成土母质不同而异，“黏质”剖面的土族控制层段矿物学类型包括高岭石混合型、混合型和伊利石型。 相似文献