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1.
土壤颗粒尺寸分布及维及对粘附行为的影响   总被引:2,自引:0,他引:2  
依据Tyler和Wheatcraft推导的土壤颗粒累积质量一尺寸标度关系,计算了我国主要土壤的颗粒尺寸分布(PSD)分维,结果表明,淡栗钙土,黄绵土,黑垆土,褐土(Lu土)潮土,灰漠土,黑土,黄棕壤,黄壤,红壤及赤红壤(砖红壤)的PSD分维依次增大,土壤粘粒含量增加使其PSD分维增大。结合土壤颗粒表面分形特性及土壤粘附的基本原理,探讨了土壤PSD分维对土壤-固体表面粘附行为的影响。PSD分维高的土  相似文献   

2.
利用X射线衍射法估算了福建省221个土壤样品中粘粒云母含量并讨论了与粘粒云母含量变化有关的因素。结果表明母质是影响粘粒云母含量的主要因素。海积物、河积物及页岩上发育的土壤粘粒云母含量一般较高;基性岩上发育的土壤粘粒云母含量一般较低。风化度较高的赤红壤、红壤、黄红壤和黄壤等土类的粘粒云母含量一般较低。风化度较低的C层的粘粒云母含量一般较B层和A层高,但异源母质的堆积可以使A层粘粒云母含量高于B层和C层。  相似文献   

3.
应用Multi-Langmuir模型评价土壤的表面电荷特性   总被引:2,自引:1,他引:1  
用返滴定技术测定土壤的可变电荷量(Qv),应用Muti-Langmuir模型评价土壤的表面电荷特性。结果表明,黄壤和黄棕壤可变电荷量的变化范围在0~45cmolkg-1,红壤为0~21cmolkg-1,砖红壤和赤红壤为0~14cmolkg-1。可变电荷量(Qv)依赖土壤悬液的pH,3点位模型能很好地描述6种土壤的可变电荷量随pH的变化关系;黄壤、黄棕壤、湖南红壤、江西红壤、赤红壤和砖红壤的pK1分别为4.45、4.46、4.76、4.62、4.66和4.74,可变电荷量Qv1分别为11.7、9.64、9.31、7.14、4.86和5.95cmolkg-1。黄壤和黄棕壤pK1较红壤、砖红壤和赤红壤约低0.3。pK1与ZPC呈现极显著的线性关系,可变电荷量(Qv(i))与有机质含量呈极显著的正相关。  相似文献   

4.
红壤中高岭类矿物的鉴定   总被引:1,自引:0,他引:1  
章明奎  何振立  M. J. Wilson 《土壤》1998,30(2):106-110
用Fomamide处理-XRD,红外(IR)和透射电镜(TEM)等方法对我国红壤的高岭类矿物进行了鉴定。结果表明:花岗岩发育的赤红壤中高岭类矿物为结晶良好的高岭石;玄武岩发育的砖红壤为无序高岭石;红壤中也以无序高岭石为主,部分样样含少量埃洛石,而发育度较低的黄壤,红砂土及泥页岩发育的黄红泥土则以埃洛石为主。  相似文献   

5.
杨德湧  蒋梅茵 《土壤学报》1991,28(3):276-283
通过粘粒矿物的定量分析,研究了我国东部花岗岩发育的红壤和黄壤的粘粒矿物组成。赤红壤、红壤和黄红壤的粘粒(<2μm)中高岭石含量分别为54%、42%和35%,这与该土壤的年均气温之间有明显的正相关(r=0.998,n=3),然而这三个土壤粘粒的风化淋溶系数与年均气温呈良好的负相关(r=1.000,n=3)。黄壤与红壤的粘粒矿物组成有明显的差异,黄壤中含有较多的三水铝石和2:1型粘土矿物,而高岭石较少;红壤中三水铝石很少,在安徽的黄红壤中虽有不少非晶质氧化铝,但未见有三水铝石存在。  相似文献   

6.
通过对云南,贵州,四川的黄壤,红壤的电化学特性研究指出:西南红壤,黄壤的可变净电荷零点pH,在3-4范围,是较低的。通过施石灰等措施提高土壤的PH而使土壤总负电荷量增加,这对淋溶作用强烈的西南红壤和黄壤的养分吸持,从而提高其保肥能力具有极为重要的实践意义,又从永久和可变电荷分别发生量的研究得知:永久电荷只占总荷量的5%-40%,可变电荷占总电荷量的60%-95%的由此说明西南红黄壤具有极其明显的可  相似文献   

7.
王明珠 《土壤》1983,15(2):59-64
我国红壤系列,包括砖红壤、赤红壤、红壤及黄壤等土类,是在热带亚热带生物气候条件下形成的。关于这类土壤的发生分类指标是否具有地带性问题,目前尚存在不同看法。  相似文献   

8.
《土壤学报》1999,36(3):8
研究了中南地区3种土壤的电荷量、电荷零点(PZC)和净电荷零点(PZNC)等表面电荷性质及其与土壤矿质组成的关系。结果表明(1)从赤红壤、红壤到黄棕壤,永久负电荷量(CECp)趋于增大,主要与土壤的粘土矿物组成和粘粒含量有关;可变负电荷量(CECv)变异趋势不明显,主要与土壤氧化铁铝的组成及含量有关;可变负电荷量占负电荷总量的比例趋于降低;正电荷量趋于减小。(2)供试赤红壤、红壤和黄棕壤的PZC分别为3.90、3.35~3.50和2.96~3.12;赤红壤和红壤的PZNC分别为3.85和2.15~2.84,黄棕壤不存在PZNC。(3)初步提出可变电荷土壤表面电荷性质的指标为PZC>3.0、PZNC>2.0、PZC朠ZNC<1.0和CECv/CEC8.2>0.4。  相似文献   

9.
研究了中南地区3种土壤的电荷量、电荷零点(PZC)和净电荷零点(PZNC)等表面电荷性质及其与土壤矿质组成的关系.结果表明:(1)从赤红壤、红壤到黄棕壤,永久负电荷量(CECp)趋于增大,主要与土壤的粘土矿物组成和粘粒含量有关;可变负电荷量(CECv)变异趋势不明显,主要与土壤氧化铁铝的组成及含量有关;可变负电荷量占负电荷总量的比例趋于降低;正电荷量趋于减小.(2)供试赤红壤、红壤和黄棕壤的PZC分别为3.90、3.35~3.50和2.96~3.12;赤红壤和红壤的PZNC分别为3.85和2.15~2.84,黄棕壤不存在PZNC.(3)初步提出可变电荷土壤表面电荷性质的指标为:PZC>3.0、PZNC>2.0、PZC朠ZNC<1.0和CECv/CEC8.2>0.4.  相似文献   

10.
福建梅花山自然保护区土壤特性及其垂直分布规律   总被引:6,自引:0,他引:6  
郭成达 《土壤学报》1992,29(4):427-436
梅花山地处中亚热带地区,基带土壤为红壤,从下而上依次分布着红壤,黄红壤和黄壤.此外,在一些千米以上的山间谷地,尚有零星的山地草甸土和沼泽土分布.各类土壤的性质均表现有一定的地带性特征.随着土壤类型的垂直地带性变化,其性质也表现较明显的地理分异规律.  相似文献   

11.
The clay minerals of more than 200 soil samples collected from various sites of Fujian Province were studied by the X-ray diffraction method and transmission electron microscopy to study their distribution and evolution.Montmorillonite was found in coastal solonchak,paddy soils derived from marine deposit,lacustrine deposit and river deposit,and some lateritic red soil,red soil and yellow soil with a low weathering degree.Chlorite existed mainly in coastal solonchak and paddy soil developed from marine deposit.1.4nm intergradient mineral appeared frequently in yellow soil,red soil and lateritic red soil.The content of 1.4nm intergradient mineral increased with the decrease of weathering degree from lateritic red soil to red soil to yellow soil.Hydrous micas were more in coastal solonchak,paddy soils derived from marine deposit,lacustrine deposit and river deposit.and puple soil from purple shale than in other soils.Kaolinte was the most important clay mineral in the soils iun this province.The higher the soil weathering degree,the more the kaolinite existed.From yellow soil to red soil to lateritic red soil,kaolinite increased gradually,Kaolinite was the predominant clay mineral accompanied by few other minerals in typical lateritic red soil. Tubular halloysite was a widespread clay mineral in soils of Fujian Province with varying quantities.The soil derived from the paent rocks rich in feldspar contained more tubular halloysite.Spheroidal halloysite was found in a red soil and a paddy soil developed from olivine basalt gibbsite in the soils in this district was largely“primary gibbsite” which formed in the early weathering stage.Gibbsite decreased with the increase of weathering degree from yellow soil to red soil to lateritic red soil.Goethite also decreased in the same sequence while hematite increased.  相似文献   

12.
Chemical reactions and fate of the toxins of Bacillus thuringiensis(Bt) in the soil environment are causing increasing concerns due to the large-scale cultivation of transgenic Bt plants.In this study,the effect of ionic strength(0-1 000 mmol kg 1) adjusted by NaCl or CaCl 2 on adsorption of Bt toxin by a lateritic red soil,a paddy soil and these soils after chemical removal of organic-bound or free Fe and Al oxides,as well as by pure minerals(goethite,hematite and gibbsite) which are widespread in these soils,were studied.The results indicated that when the supporting electrolyte was NaCl,the adsorption of Bt toxin by the lateritic red soil and paddy soil increased rapidly until the ionic strength reached 250 mmol kg 1 and then gradually slowed down with the increase of ionic strength;while in case the supporting electrolyte was CaCl 2,the adsorption of Bt toxin enhanced significantly at low ionic strength(< 10 mmol kg 1) and then decreased as the ionic strength increased.The adsorption of Bt toxin by the tested minerals and soils after the removal of organic-bound or free Fe and Al oxides also increased with increasing ionic strength controlled by NaCl.Removing organic-bound Fe and Al oxides obviously increased the adsorption of Bt toxin in the tested soils.Differently,removing free Fe and Al oxides increased the Bt adsorption by the paddy soil,but decreased the adsorption by the lateritic red soil.The study indicated that the varieties of ionic strength and the presence of Fe and Al oxides affected the adsorption of Bt toxin by the soils,which would contribute to the further understanding of the fate of Bt toxin in the soil environment and provide references for the ecological risk assessment of transgenic Bt plants.  相似文献   

13.
The phosphate adsorption and surface charge characteristics of the tropical and subtropical soils derived from different parent materials in China were determined, and their relations to soil mineralogy were analysed. The results showed that all soil phosphate adsorption curves were well fitted by Freundlich equation and Langmuir equation. The maximum buffering capacity of P ranged from 66 to 9 880 mg kg-1, with an increasing order of purple soil, skeletal soil, red soil, lateritic red soil, yellow soil and latosol; and the highest value was 149 times the lowest value, which indicated great differences among these soils in phosphate adsorption and supplying characteristics. The pH0 (zero point of charge) values obtained by salt titration-potential titration varied from 3.03 to 5.49, and the highest value was found in the latosol derived from basalt whereas the lowest value was found in the purple soil. The correlation analysis indicated that the main minerals responsible for phosphate adsorption in the soils were gibbsite, amorphous iron oxide and kaolinite; and the pH0 was mainly controlled by kaolinite, gibbsite and oxides.  相似文献   

14.
对黄壤发生分类的看法   总被引:3,自引:0,他引:3  
叶仲节 《土壤学报》1984,21(4):447-454
长期以来我们对黄壤的发生、特性和分布总觉得模糊不清。在土壤调查制图时;因红壤黄壤在形态性质上不易区分,所以在确定南方山地红壤带和黄壤带的垂直分布界线时,只有按海拔高度来划分。1982年10月在重庆召开的第三次全国森林土壤学术讨论会上有两篇都是有关广东鼎湖山的土壤论文,其中一篇把红壤黄壤界线划在300米,而另一篇划在700米,说明划分标准还不统一。云贵高原是我国黄壤集中分布区,根据已有的资料看来,那里的黄壤是否典型、黄壤是否为湿润气候的产物,都值得讨论。本文就多年来的考察,结合有关论著,谈一点不成熟的看法,希望能起到抛砖引玉的作用。  相似文献   

15.
The study about the adsorption of phosphate on four variable charge soils and some minerals revealed that two stage adsorption appeared in the adsorption isotherms of phosphate on 4 soils and there was a maximum adsorption on Al-oxide-typed surfaces between pH 3.5 to pH 5.5 as suspension pH changed from 2 to 9, but the adsorption amount of phosphate decreased continually as pH rose on Fe-oxide typed surfaces. The adsorption amount of phosphate and the maximum phosphate adsorption pH decreased in the order of yellow-red soil > lateritic red soil > red soil > paddy soil, which was coincided with the content order of amorphous Al oxide. The removement of organic matter and Fe oxide made the maximum phosphate adsorption pH rise from 4.0 to 5.0 and 4.5, respectively. The desorption curves with pH of four soils showed that phosphate desorbed least at pH 5. Generally the desorption was contrary to the adsorption with pH changing.  相似文献   

16.
研究了中南地区3种土壤的电荷量,电荷零点和净电荷零点等表面电荷性质及其与土壤矿物组成的关系,结果表明:(1)从赤红壤,红壤到黄棕壤,永久负电荷量趋于增大,主要与土壤的粘土矿物组成和粘粒含量有关,可变负电荷量变异有明显,  相似文献   

17.
新垦赤红壤结构特性的演化   总被引:4,自引:3,他引:4       下载免费PDF全文
本文探讨新垦赤红壤结构特性的变化,定位试验结果表明:在亚热带生物气候条件下垦殖赤红壤,由于耕作管理扰动土壤,将不可避免地产生土壤砂化或粉砂化现象。  相似文献   

18.
The changes of clay mineral association after high-gradient magnetic separation(HGMS) treatment,and the effects of chemical and physical technologies on concentrating Fe oxides for mian soils in central and southern China were investigated by means of X-ray diffraction (XRD) and chemical analysis methods.Results indicated that the concentrating times of Fe oxides by HGMS treatment were the largest for 0.2-2μm size fraction in the examined soils .For the soils in which 2:1 phyllosilicates were dominant,concentrating times of iron oxides by HGMS treatment were larger than by 5 mol L^-1 NaOH treatment .Phyllosili-cates were decreased after HGMS treatment ;however,the decrease was less than that of kaolinite,The goethite/(goethite hematite) values in Fe oxides of the soils kept virtually constant after HGMS treatment.  相似文献   

19.
熊东  夏建国 《农业环境保护》2012,(11):2160-2173
选取名山河流域4种土地利用方式(林地、水田、茶园、旱地)的黄壤为研究对象,采用平衡液等温吸附法和NH4OAC、EDTA溶液解吸法,研究土壤组分(有机质、游离氧化铁)对微团聚体吸附解吸Cd2+的影响。结果表明:去除土壤组分前后,原土及各粒径微团聚体对Cd2+的吸附量均随Cd2+初始浓度增大而增大,吸附量均按以下次序递减:(〈0.002mm)〉2~0.25mm〉原土〉0.053~0.002mm〉0.25~0.053mm,与有机质、游离氧化铁、CEC呈极显著正相关。吸附减少量大小关系为:去除有机质〉去除游离氧化铁,有机质的贡献率大于游离氧化铁。Freundlich方程拟合效果最佳,达到极显著水平,分布系数Kd值与Cd2+初始浓度呈曲线负相关。NH4OAC解吸率随原吸附Cd2+初始浓度增大而增大,以最大解吸率计,递减规律为:0.25~0.053mm〉0.053~0.002mm〉原土〉2~0.25mm〉(〈0.002mm);EDTA解吸率随原吸附Cd2+初始浓度增大而减小,递减规律与NH4OAC解吸率相反。去除土壤组分后,NH4OAC解吸率上升,EDTA解吸率下降,茶园与旱地黄壤非解吸率减小,林地与水田黄壤非解吸率增大。去除土壤组分后,非专性吸附与吸附总量呈极显著正相关,专性吸附与吸附总量呈极显著负相关。  相似文献   

20.
福建东南部山地丘陵土壤的基本特征   总被引:8,自引:0,他引:8  
福建是我国多山的省份之一.东南部靠山面海,以戴云山为主体的闽中大山带分布于本区西北部,平均高度为海拔800-1000米以上,成东北西南走向,其支脉密布本区,地势由西北向东南倾斜,呈阶梯状下降,由中山过渡到低山、丘陵、台地直至海滨狭小的海积-冲积平原.  相似文献   

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