首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
用(NH4)2SO4-浓H2SO4-二胺替吡啉甲烷比色法和NaOH熔融-二胺替吡啉甲烷比色法,分别提取和测定了四川盆地几种主要紫色母岩和土壤中无定型TiO2和全钛。将“全TiO2/无定型TiO2”定义为“钛值”,并用钛值代替硅铝铁率衡量紫色母岩的风化程度。结果为:四川盆地的六种紫色母岩中全钛含量变化于2.95~20.0gkg^-1(TiO2)之间,属中等偏高水平;不同岩性间趋势为泥页岩〉泥岩〉粉砂岩〉砂岩;全量TiO2与岩石的总SiO2含量呈显著的负相关(r=-0.7459^*)。钛值的大小与风化度呈反相关,按钛值的大小,各紫色母岩原始风化度大小顺序如下:三叠纪飞仙关(T1f)〈侏罗纪沙溪庙(J2s)〈侏罗纪自流井(J1-2z)〈侏罗纪蓬莱镇(J3p)〈侏罗纪遂宁组(J3s)〈白垩纪夹关组(K2j)。紫色土壤钛值所反映的风化度与硅铝铁率基本吻合,二者的相关性达到极显著水平(r=0.8615^**)。而土壤胶体的钛值与硅铝铁率的相关系数r=0.8757^**,达极显著相关。土壤钛值所反映的风化度水平与紫色母岩的风化度趋势一致。  相似文献   

2.
The system SiO2 -AlOOH-Fe2 O3 -H2 O is used to show certain short-comings in the use of single minerals to index weathering stages. An alternative (analogous to the metamorphic facies concept) is proposed in which three stages are recognized, one of which can already be defined in terms of mineral assemblages, while the two earlier stages should eventually prove open to this treatment.  相似文献   

3.
QUANTIFICATION OF WEATHERING, SOIL GEOCHEMISTRY AND SOIL FERTILITY   总被引:2,自引:0,他引:2  
Continental chemical weathering is discussed with reference to a diagram, in which the ratio (CaO + Na2O + K2O)/(Al2O3+ CaO + Na2O + K2O) is plotted against the ratio (SiO2+ CaO + Na2O + K2O)/(Al2O3+ SiO2+ Na2O + K2O). The former ratio is a measure of the degree of feldspar breakdown, which is accompanied by the formation of secondary minerals (illite, smectite, etc.). The second ratio is a measure of the enrichment during weathering of Al, Si oxide phases such as kaolinite, quartz and gibbsite. The application of the diagram to a series of global examples leads to the statement: 1) Chemical weathering is the principal process by which continental surfaces are modified. 2) The extent of chemical weathering is correlated with the age of continental surfaces. 3) Global agricultural productivity is correlated with geologically recent additions of fresh rock debris by processes of volcanism, glaciation or alluviation.  相似文献   

4.
Abstract

We have studied the chemical and mineralogical characteristics of ophites located in a diapiric formation in Burgos (North of Spain), and the soils derived from them. The ophites studied show mineralogical uniformity. Their main components are clinopyroxenes, plagioclases, biotite, and olivine. Generally, they show deuteric alteration mainly affecting the olivine. The presence of talc is attributed to an outpouring of basic magma (ophite) in an evapotiric environment of Keuper facies. Chemically, they are basic rocks, of basaltic nature, poor in silicon dioxide (SiO2) and rich in magnesium oxide (MgO) and ferric oxides (Fe2O3). The weathering of the ophites results in clay consisting of chlorite, vermiculite, and interlayer chlorite‐vermiculite‐smectite inherited from original material. Small amount of extractable silica (Si), aluminum (Al), and iron (Fe) show the scarcity of amorphous material attributed to the high content in organic carbon (C) which prevents formation of allophane, and to the xeric moisture regime of soils in this location.  相似文献   

5.
昆明地区不同母质对红壤发育的影响   总被引:6,自引:0,他引:6  
趙其国 《土壤学报》1964,12(3):253-265
昆明地区位于云南省中部,为我国西南高原红壤的主要分布区。关于本区土壤形成过程及发生分类等同题,虽然曾有人做过不少工作,但至今仍存在着一些分歧;有人认为本区土壤的形成过程以砖红壤化为主,土壤类型为砖红壤及铁质砖红壤性土[1,2];有人认为棕壤化为本区土壤的主要成土过程,土壤应命名为棕色森林土[4];另有人认为本区土壤属红壤,目前的成土过程为红壤化[5],所有这些意见,均因资料不足而难取得统一。  相似文献   

6.
湘中下寒武统黑色页岩土壤的地球化学特征   总被引:11,自引:0,他引:11  
以湘中发育于下寒武统黑色页岩之上的土壤为研究对象,选择安化东坪、烟溪,桃江,宁乡等地的典型土壤及相应成土母岩,利用等离子质谱(ICP-MS)、X射线荧光光谱(XRF)等分析技术,对土壤、成土母岩(黑色页岩)的主量元素和微量元素(包括重金属元素、稀土元素等)进行了较系统的分析测定。结果表明,湘中下寒武统黑色页岩土壤风化作用强烈,风化指数CIA均在73以上。强烈的风化使得土壤具有明显贫CaO、Na2O,而富Al2O3、Fe2O3的化学组成特征。土壤因继承成土母岩(黑色页岩)的特征而富集Mo、Cd、Sn、Sb、U、V、Cr、Co、Ni、Cu、Zn、Tl、Pb、Th等多种重金属元素,其综合富集指数(EI值)平均在3以上,最高达17。地质累计指数(Igeo)评价结果显示,土壤重金属的富集已达到污染程度,土壤存在Cd、Mo、Sb、U、Sn、V、Cu、Tl、Ba等重金属的污染,并以Cd、Mo、Sb等重金属污染最强,达中度至极强污染程度。重金属与主量元素的相关性分析显示,土壤中的重金属主要赋存于黏土矿物和铁氧化物(针铁矿)等矿物相中,其中Ba、Sn、Th、Cu、Sc等主要赋存黏土矿物中;Zn、Ni、Mn、Co、Cd、Tl、Pb等则主要赋存于铁氧化物矿物(针铁矿)中;而Cr、V、Mo、Sb、U等则不受黏土矿物和铁氧化物矿物的控制。此外,不同地区土壤的Zr/Hf、Ta/Nb、Nd/Sm等元素比值相对稳定,依次为36.20、0.085、5.30(n=73),并与相应的成土母岩(黑色页岩)相应值基本一致。土壤与成土母岩具有相同的稀土配分型式,且成土过程中稀土元素不发生明显的分异。微量元素比值和稀土元素特征指示土壤中的重金属来自成土母岩(黑色页岩)本身,为自然污染源。  相似文献   

7.
Material balance in an aquic Hapludalf from loess by means of IR-phase analysis Grain size fractions of an aquic Hapludalf from loess near Göttingen were examined mineralogically and chemically. On the base of actual mineral composition (mode) by means of infrared spectroscopy weathering balances were made up. The results reveal a strong illite/mica loss of about 80 kg/m2, which is due to decomposition in the A-horizon, and which is not compensated by a slight gain in the B-horizon. The mineral balance of the total profile yields a clay degradation of 44 kg/m2. Furthermore, in the A-horizon the chemical balance gives evidence of considerable mobilizations and substantial losses mainly of SiO2, Al2O3, MgO and K2O combined in silicates. Depending on soil horizons and grain sizes the illites have K-contents varying from 4 to 8% K2O. Al2O3 and MgO also show distinct variations. Both components are correlated negatively and decrease (Al2O3) respectively increase (MgO) from the top to the bottom.  相似文献   

8.
The study was investigated at Agricultural Experimental Farm, Giridih, India during winter seasons of 2007–2008 and 2008–2009. Plants grown with 100% recommended dose of fertilizer (RDF) [nitrogen (N): phosphorus pentoxide (P2O5): potassium oxide (K2O) = 150:60:60 kg ha?1] + AM + Azospirillum (T15) produced maximum chlorophyll, baby cob, and green fodder yield. Root biomass was highest with application of 150% RDF + arbuscular mycorrhizae (AM) + Azospirillum (T16). Co-inoculated plants produced higher chlorophyll, root biomass resulted higher cob and green fodder yield. Biofertilizers supplied along with chemical fertilizers saved 70, 29, and 33 kg N, P2O5 and K2O per hectare, respectively. Nutrient (NPK) uptake was greatest in T15. Residual soil fertility in terms of NPK was recorded maximum in T16. Although, co-inoculated plots built up higher residual soil fertility as compare to sole inoculation. Nutrients use efficiency and benefit cost ratio were higher due to application of 50% RDF with co-inoculants. T16 was most costly whereas T14 (50% RDF + AM + Azospirillum) was most beneficial.  相似文献   

9.
江苏省土壤钾素的供应能力与钾肥施用问题   总被引:3,自引:0,他引:3  
随着我国农业生产的不断发展,复种指数和单位面积产量的不断提高,南方不少地区施用钾肥已成为夺取高产稳产的重要条件之一,有关土壤钾素状况和钾肥施用问题愈来愈受到人们的重视.江苏省地处我国南北的过渡带,其土壤是否缺钾,钾肥的需要程度如何,是生产实践上有待明确的一个问题.  相似文献   

10.
Ward Chesworth 《Geoderma》1973,10(3):215-225
Weathering trends emanating from the compositional field of the common igneous rocks, can be shown graphically to converge on compositions relatively rich in SiO2, Al2O3 and Fe2O3. This convergence means that in chemical terms, the effect of the composition of igneous parent rock on the composition of the resulting soil, is an inverse function of time. Given enough time the chemical effect of parent rock would be nullified. The consequences of this to “state factor equations” are indicated.  相似文献   

11.
Based on chemical and mechanical compositions and quartz content of red and/or yellow colored soil materials in the southwestern part of Japan, lithology index (LI) and weathering index (WI) were derived using a multivariate statistical method (factor analysis). The variables used for factor analysis are Fe2O3/Al2O3, TiO2/Al2O3, Fe2O3+Al2O3+Quartz, Si(non-quartz)/(Fe2O3 + Al2O3), CaO + MgO + K2O3, MgO/K2O3 and Quartz/Sand, all of which represent certain different aspects of weathering and/or Iithological characteristics. Since LI and WI are mutually independent, it is possible to evaluate the effect of the degree of weathering on the characteristics of red and/or yellow colored soil materials independently from that of lithology.  相似文献   

12.
The clay mineralogy of two red-black soil toposequences on basic igneous rocks in Kenya has been investigated. Besides some illite and amorphous material kaolinites predominate in the slope soils (ultisols) whereas smectites are the main clay minerals in the soils of the depressions (vertisols). The kaolinites are poorly crystalline and have high surface area. According to chemical analysis, IR spectroscopy, and D.T.A. the smectites appear to be a ferriferous member of the montmorillonite-beidellite series having approximately 0·5 Fe3+ in octahedral and 0·2 Al per O10(OH)2 in the tetrahedral position. The profile and slope distribution of kaolinites and smectites led to the conclusion that the smectites are the first weathering product and, depending on hydrological conditions governing the soil solution composition (Si, Mg, pH), either persist (depression) or are decomposed (slope) and followed by kaolinites.  相似文献   

13.
《CATENA》1988,15(5):417-432
In the South-Eastern part of Guinea Bissau extensive, highly weathered ferrallitic mantles occur within different geomorphological levels. These weathered layers are usually capped by petroplinthite. Frequently, they are of economic interest due to their enrichment in alumina. They represent the remnants of a Mezo-Cainozoic “African Planation Surface”. One hundred auger drill samples from one geomorphological structure—Bowal, were submitted to a specially developed method of quantification of the mineral phases previously detected in the representative specimens of the batch. The method consisted of computing the mineralogical composition from the principal chemical component analyses (Al2O3, SiO2, Fe2O3, TiO2, H2O) combined with DTA/TG studies and thermodifferential X-ray diffraction studies. In addition, the samples from available core drillings, which reached the parent rocks, were investigated by means of XRD and optical microscopy. Two groups of bauxites developed on dolerite and shale yield the same mineral paragenese. The differences of mean Al2O3 and Fe2O3 content in both groups are expressed entirely by differences of concentration of gibbsite and goethite, which reflect mobility of aluminium and iron in solutions circulating through the system of open large pores. Boehmite and hematite would tend to crystallize from oversaturated solutions in confined environment of fine pores.  相似文献   

14.
新疆博格达山北坡土壤形成特征及其垂直分布   总被引:3,自引:0,他引:3  
刘立诚 《土壤学报》1987,24(1):77-85
博格达山北坡土壤形成过程主要有腐殖质化过程、粘化过程、钙他过程、残余盐化-碱化过程、高山融冻过程.土壤风化程度低,粘土矿物以伊利石为主,粘粒SiO2/R2O3为2.84-3.54,各土类差别不大,R2O3,沿剖面无明显移动.本区山体高大,土壤垂直分布完整,在天山北坡有代表性,并具温带荒漠土壤的垂直分布特点.土壤垂直分布东、西差异明显,西部完整,东部无荒漠土壤和高山草甸土.  相似文献   

15.
黎耀辉 《土壤学报》1965,13(1):39-45
我国北方石灰性土壤上磷肥的肥效,很不稳定。近年来各地围绕着这一问题,进行了一些工作。大体看来,着重在肥料配合、施用方法、磷肥品种和作物种类对磷肥肥效影响的报道较多。至于土壤本身对于磷肥肥效的影响,研究的还少。  相似文献   

16.
Poor quality of irrigation water (high salinity) has reduced the yields of pistachio over recent years, especially in Kerman. The effects of four salinity levels [0, 30, 60, and 90 mM sodium chloride (NaCl)] and three calcium (Ca) levels [0, 0.5, and 1 mM Ca as calcium nitrate (Ca(NO3)2.4H2O)] on growth and chemical composition of pistachio seedlings cv. ‘Badami’ were studied in sand culture under greenhouse conditions in completely randomized design (CRD) with four replications. After 170 days, leaf area, leaf number, shoot and root dry weights were determined. Also shoot and root sodium (Na), potassium (K), Ca, and magnesium (Mg) concentrations were measured. Results showed salinity decreased all growth parameters. Ca application increased shoot and root Ca concentrations and root K concentration, while Ca application decreased shoot K concentration and shoot and root Mg concentrations. Salinity decreased shoot Ca, root K, and root Mg concentrations, while salinity increased shoot and root total sodium uptake, and shoot and root Cl concentrations.  相似文献   

17.
氮磷钾硼对甘蓝型黄籽油菜产量和品质的影响   总被引:22,自引:2,他引:22       下载免费PDF全文
采用四元二次回归正交旋转组合设计,以氮(N)、磷(P)、钾(K)、硼(B)肥为主要探讨因子进行田间试验,建立N、P、K、B4因素与黄籽油菜籽粒产量、含油量、产油量以及蛋白质含量的施肥模型。对模型解析发现,在供试条件下N、P、K、B单因子对产量和产油量的影响均是X1(N)>X2(P2O5)>X4(B)>X3(K2O),对含油量的影响是X1(N)>X4(B)>X2(P2O5)>X3(K2O),对蛋白质的影响为X1(N)>X4(B)>X3(K2O)>X2(P2O5)。施肥模型寻优结果表明施N163.7~179.2kghm-2、P2O585.0~95.0kghm-2、K2O100.7~124.3kghm-2、B6.7~8.3kghm-2,可使黄籽油菜产油量达到1000kghm-2,饼粕蛋白质含量达40%以上;饼粕蛋白质含量大于45%时,各养分因子的取值区域分别是施N236.6~255.4kghm-2、P2O580.3~99.7kghm-2、KO103.2~126.8kghm-2、B8.9~10.3kghm-2。  相似文献   

18.
玄武岩发育的几种红壤的矿物特征   总被引:5,自引:0,他引:5       下载免费PDF全文
蒋梅茵  杨德湧 《土壤学报》1991,28(3):268-275
本文主要研究不同生物气候条件下由玄武岩母质发育的红壤、赤红壤和砖红壤的理化性质及矿物组成。粘粒中氧化铁的含量都很高,为16.98±0.83%。砖红壤与赤红壤粘粒中高岭石与非晶物质的含量相近,它们之间的差异是赤红壤中没有三水铝石,而含有7—11%蒙皂石。红壤粘粒中高岭石和非晶物质的含量都低于砖红壤和赤红壤,而水云母和蒙皂石的含量较高,也没有三水铝石。粘粒含量、阳离子交换量、硅铝率、硅铁铝率、铁的游离度和风化淋溶系数等都反映了土壤风化程度上的差异,它与水热条件特别是年均温和积温有关,进一步说明生物气候因素引起的土壤性质及矿物组成变化比其它因素强烈。砖红壤与砖红壤性水稻土的差异是在氧化铁形态上;红壤与红壤性水稻土相比,后者粘粒中蒙皂石含量略高,水云母含量略低。  相似文献   

19.
In order to investigate the paleoclimatic changes in S China during the late Quaternary and their influence on pedogenesis and soil classification, a yellow‐brown earth (YBE)–red clay (RC) profile in Langxi County, Anhui Province was studied. The grain‐size distribution and the major‐ and trace‐element compositions of the profile indicate that the YBE of the profile shares the same origin with the YBE in Jiujiang and Xuancheng and the Xiashu loess in Zhenjiang, and the underlying RC also has aeolian characteristics and shares the same origin with the Xiashu loess. Grain‐size characteristics, molecular ratios of SiO2/Al2O3, SiO2/(Al2O3+Fe2O3), and BA ([CaO+MgO+K2O+Na2O]/Al2O3) and other weathering indices (CaO/TiO2, MgO/TiO2, K2O/TiO2, Na2O/TiO2, and Rb/Sr) of the profile indicate that the RC is more strongly weathered than the YBE. Magnetic susceptibility (χlf) of the uniform red clay (URC) of the profile is significantly enhanced. However, that of the underlying reticulate red clay (RRC) is significantly decreased because of the paleogroundwater movement and cannot indicate its strong weathering properties. The YBE‐RC profile in Langxi County recorded a great climatic change during late Quaternary: At that time, the pedogenic development of the RC was terminated and widespread dust deposition occurred. The parent material of the RC may be aeolian deposits which were accumulated before the last interglacial and were strongly weathered and rubified under the subsequent interglacial climate. It is observed that red soils, derived from the RC, and yellow‐brown soils, derived from the YBE, coexist in the study area, which is contradictive to the theory of the zonal distribution of soils. Therefore, it is necessary to take into account the history of Quaternary climatic changes when studying pedogenesis.  相似文献   

20.
Chemical and mineralogical properties of five soil profiles of a catena in Iperu, Western State of Nigeria, are reported. The pH values of the subsoils are extremely acid. Acidity decreases with improved drainage in the subsoils (pH 4.0–5.8). The cation exchange capacity (C.E.C.) of the soils range from 3.0 to 16.2 me/100g of soil. The silt: silt+clay ratio, calcium: magnesium ratio and Fe2O3:Al2O3 ratio are used as weathering indices. The low values of the silt: silt + clay index indicate that the soils must have undergone advanced weathering. The magnitude of the Ca: Mg ratio indicates that more calcium than magnesium is available in the soils. The values for sodium and potassium are extremely low. More iron than aluminium was extracted from the soils by the dithionite-citrate method. Kaolinite is the most abundant clay mineral. Halloysite, interstratified clay materials, vermiculite, quartz, and mica are present in considerable amounts. The silt fraction in which quartz is the most abundant mineral, also contain some kaolinite and mica.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号