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1.
利用粘粒矿物修复重金属污染农业土壤研究进展 总被引：16，自引：2，他引：14
Heavy metal contamination of agricultural soils poses risks and hazards to humans.The remediation of heavy metal-polluted soils has become a hot topic in environmental science and engineering.In this review,the application of clay minerals for the remediation of heavy metal-polluted agricultural soils is summarized,in terms of their remediation effects and mechanisms,influencing factors,and future focus.Typical clay minerals,natural sepiolite,palygorskite,and bentonite,have been widely utilized for the in-situ immobilization of heavy metals in soils,especially Cd-polluted paddy soils and wastewater-irrigated farmland soils.Clay minerals are able to increase soil pH,decrease the chemical-extractable fractions and bioavailability of heavy metals in soils,and reduce the heavy metal contents in edible parts of plants.The immobilization effects have been confirmed in field-scale demonstrations and pot trials.Clay minerals can improve the environmental quality of soils and alleviate the hazards of heavy metals to plants.As main factors affecting the immobilization effects,the pH and water condition of soils have drawn academic attention.The remediation mechanisms mainly include liming,precipitation,and sorption effects.However,the molecular mechanisms of microscopic immobilization are unclear.Future studies should focus on the long-term stability and improvement of clay minerals in order to obtain a better remediation effect. 相似文献
2.
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
3.
粘土矿物中钾的生物活化: Ⅰ. 外生菌根 总被引：1，自引：0，他引：1
A pot experiment was Carried out to in vestigate effect of ectomycorrhizal fungi on eucalyptus growth and K bio-mobilization from soils and clay minerals,In the experiment,sands mixed with soil,KCl-satureated vermiculate and mica,respectively,were used to nurse eucalypus seedings which were nonectomycorrhized or ectomycorrhized by an ectomycorrhizal fungus Pisolithus tinctorius strain XL1(Pt XC1) isolated from a forest soil from Xichang,Sichuan Province,China,and a worldwide well-know ectomycorrhial fungus Pioslithus tinctorius strain 2144(Pt 2144) obtained in Australia.More depletion of HCl-souluble K by mycorrhizas from the soil and minerals than nomycorrhizas suggested that mycorrhizas had a great ability to mobilize K present in the interlayer and feldspar.Mycorrhizal seedlings depressed greatly K digested with HF-HClO4 from substrates after consecutive extractions of soils and minerals by water,ammonium acetate and boiling HCl,while nonmycorrhizal seedlings reduced it little if any,shwing that the mycorrhizal seedlings could mobilize and then utilize the structureal K in mineral lattice,Ectomycorrhizal fungi played a very important role not only in promoting the growth of eucalyptus seedlings but also in mobilizing K in soils and minerals.The infection of Pt XC1 led to a better growth of eucalyptus seedlings and more K accumulation in the seedlings than that of Pt 2144.The large differeces in K accumulation by the seedlings might be due to different abilityes of the two ectomycorrhizal fungi to mobilize K in intelayer and lattice pools in the clay minerals. 相似文献
4.
The particle-size distribution and mineralogical composition of the clay (< 2 μm) and fine-sand (0.25--0.10 mm) fractions in soils of two inland valleys in Abakaliki and Bende, Southeast Nigeria, were investigated to provide basic information on soil-forming processes and agricultural potentials. These soils were silty or clayey, deriving from Cretaceous or Tertiary shale materials. The particle-size distribution and its computation on a clay-free basis revealed relatively remarkable lithologic breaks in a couple of pedons. The effect of lithologic discontinuities on soil mineralogical composition was not, however, conspicuous. Petrographic investigation revealed that quartz predominantly comprised the fine-sand fraction in the soils at both study sites. Nevertheless, the clay mineralogical composition of the soils was a mixture of kaolinite, irregularly interstratified smectite-illite intergrades (S/I), hydroxyl-Al interlayered 2:1 type clays (HICs), vermiculite, smectite, halloysite and illite along with fine-sized quartz in Abakaliki. The soils of Bende predominantly contained smectite, which was partially interlayered with hydroxyl-Al and kaolinite. It is suggested that seasonal floodwater has slowed the disintegration of weatherable clay minerals inherited from the shale, while quartz originating from the sandstone is predominant in the fine-sand fraction. Additionally, a possible soil-forming process observed at the both study sites was ferrolysis, which was indicated by a clear decreasing pattern of HICs downward in the soil profiles. The entry of S/I and vertical distribution patterns for a couple of clay minerals in the pedon suggested that the soils in Abakaliki have developed under the significant influence of aeolian dust delivered by the harmattan. The findings might describe a site-specific deposition pattern of harmattan dusts as well as hydromorphic soil-forming processes in the wetlands of the inland valleys. 相似文献
5.
大田条件下水稻败育与铜缺乏的关系 总被引：1，自引：0，他引：1
The effect of liming 4 soils developed from Quaternary red clay and red sandstone on the cadmium forms and its toxicity were investigated.Liming the acid red soils could greatly reduce Cd toxicity to plants because the soluble Cd and organic Cd in the soils decreased significantly while Cd bound to minerals/oxides and residual Cd increased markedly with increasing lime rates(pH). 相似文献
6.
湿润速率和粘粒含量对红壤沟间侵蚀的影响 总被引：4，自引：0，他引：4
An aggregate stability test and a simulated rainfall test were conducted on four representative Ultisols from southeastern China. The soils selected, with clay contents ranging between 117 and 580 g kg-1 , were derived from shale and Quaternary red clay. The stability of aggregates (2–5 mm in diameter) obtained from the soil samples were determined by the Le Bissonnais method. For determination of infiltration, runoff, and erosion, the soil samples were packed in 30 cm × 60 cm trays, wetted at rates of 2, 10, and 60 mm h-1 , and then exposed to simulated rainfall at 60 mm h-1 for 1 h. The results indicated that both aggregate stability and slaking caused by fast wetting increased with increasing clay content. The effect of wetting rate (WR) on infiltration and seal formation varied with clay contents. In the soil with low clay content (sandy loam), the infiltration rate was affected slightly by WR due to low aggregate stability and slaking. In the soils with medium clay content (silt clay loam and clay), WR affected infiltration significantly due to the high aggregate slaking force. In the soil with high clay content, the effect of WR on infiltration was significant, but not as evident as in the soils with medium clay content, which may be related to high aggregate stability by wetting partially compensating for slaking force. The effect of WR on soil loss was similar to that of runoff, but more pronounced. The findings from this study indicated that the relationship between wetting rate and clay content should be considered when predicting interrill erosion in Ultisols. 相似文献
7.
Addition of clay-rich subsoil to sandy soil results in heterogeneous soil with clay peds(2-mm) or finely ground( 2 mm) clay soil(FG), which may affect the nutrient availability. The aim of this study was to assess the effect of clay soil particle size(FG or peds)and properties on nutrient availability and organic C binding in sandy soil after addition of residues with low(young kikuyu grass,KG) or high(faba bean, FB) C/N ratio. Two clay soils with high and low smectite percentage, clay and exchangeable Fe and Al were added to a sandy soil at a rate of 20%(weight/weight) either as FG or peds. Over 45 d, available N and P as well as microbial biomass N and P concentrations and cumulative respiration were greater in soils with residues of KG than FB. For soils with KG residues,clay addition increased available N and initial microbial biomass C and N concentrations, but decreased cumulative respiration and P availability compared to sandy soil without clay. Differences in measured parameters between clay type and size were inconsistent and varied with time except the increase in total organic C in the 53 μm fraction during the experiment, which was greater for soils with FG than with peds. We concluded that the high exchangeable Fe and Al concentrations in the low-smectite clay soil can compensate a lower clay concentration and proportion of smectite with respect to binding of organic matter and nutrients. 相似文献
8.
石灰处理对红壤中镉形态及其毒性的影响 总被引：1，自引：0，他引：1
The effect of liming 4 red soils developed from Quaternary red clay and red sandstone on the cadmium forms and its toxicity were investigated. Liming the acid red soils could greatly reduce Cd toxicity to plants because the soluble Cd and organic Cd in the soils decreased significantly while Cd bound to minerals/oxides and residual Cd increased markedly with increasing lime rates (pH). 相似文献
9.
亚热带土壤不同矿物组分中铬的吸附 总被引：1，自引：0，他引：1
J. BAVARESCO J. R. FINK M. L. K. RODRIGUES C. GIANELLO V. BARR&#;N J. TORRENT 《土壤圈》2017,27(1):106-111
Safe application of chromium (Cr)-containing organic industrial wastes to soil requires considering the ability of the soil to adsorb Cr.In this study,the maximum Cr adsorption capacity was assessed for the bulk samples and their clay and iron-free clay fractions of four subtropical soils differing in mineralogy.To this end,the samples were supplied with Cr(Ⅲ) nitrate solutions at pH 4.5 or 5.5.The results of Cr(Ⅲ) adsorption fitted to a Freundlich equation and the adsorption capacity was positively correlated with soil organic matter and iron oxide contents.The clay fractions adsorbed more Cr per unit mass than the bulk soils and the iron-free clay fractions.The Cr(Ⅲ) adsorption capacity increased with increasing soil pH due to more charges on adsorbing surfaces.Our results suggest that the soils rich in organic matter and iron oxides and having a pH above 4.5 are suitable for application of Cr(Ⅲ)-loaded industrial wastes. 相似文献
10.
The zero point of charge (ZPC) and the remaining charge σp at ZPC are two important parameters characterizing surface charge of red soils.Fourteen red soil samples of different soil type and parent material were treated with dithionite-citrate-dicarbonate (DCB) and Na2CO3 respectively.ZPC and σp of the samples in three indifferent electrolytes (NaCl,Na2SO4,and NaH2PO4) were determined.Kaolinite was used as reference.The results showed that ZPC of red soils was affected by the composition of parent materials and clay minerals and in significantly positive correlation with the content of total iron oxide (Fet),free iron oxide (Fed),amorphous iron oxide (Feo),aluminum oxide (Alo) and clay,but it was negatively correlated with the content of total silica (Sit).The σp of red soils was also markedly influenced by mineral components.Organic components were also contributing factor to the value of σp.The surface charges of red soils were evidently affected by the constitution of the electrolytes.Specific adsorption of anions in the electrolytes tended to make the ZPC of red soils shift to a higher pH value and to increase positive surface charges of the soils,thus leading to change of the σp value and decrease of the remaining net negative charges,even to the soils becoming net positive charge carriers.The effect of phosphate anion was greater than that of sulfate ion. 相似文献
11.
土壤可见光-近红外反射光谱与重金属含量之间的相关性 总被引：13，自引：0，他引：13
发展基于反射光谱技术的快速、简便、低成本的土壤重金属信息提取方法是区域土壤重金属污染治理所需要的。选择江西贵溪铜冶炼厂污染区,分析了9种重金属元素(Cu、Pb、Zn、Cd、Co、Ni、Fe、Mn及Cr)与土壤可见光-近红外反射光谱之间的相关性及其相关的原因。研究表明,研究区土壤中存在Cu(含量介于66.71~387 mg kg-1之间)和Cd(含量介于0.36~6.019 mg kg-1之间)的强烈富集。土壤重金属含量与反射光谱之间存在显著相关,污染元素Cu的最高相关系数为-0.87,Pb、Zn、Co、Ni、Fe的最高相关系数达到高度相关(|r|>0.80),Cr、Cd、Mn的最高相关系数达到显著相关(|r|>0.70)。微分光谱适于获取土壤中的重金属元素信息,利用组合波段能显著提高相关性。Cu与反射光谱之间的相关性主要受有机质的影响;Pb、Zn、Co、Ni主要受黏土矿物和铁锰氧化物的影响;Cr与反射光谱之间的相关性同时受有机质和黏土矿物的影响。 相似文献
12.
采用批量平衡试验,研究了不同土壤及长黏土矿物对多氯联苯吸附特性。结果表明:多氯联苯浓度范围为0.25~5.0mg L-1时,不同土壤及黏土矿物对多氯联苯的吸附均能用Freundlich方程很好地拟合,随着溶液中多氯联苯浓度的增加,土壤及黏土矿物对多氯联苯的吸附量增加;几种土壤对多氯联苯吸附量大小顺序为:红壤>黄褐土>砂姜黑土,土壤有机质、粘粒等对多氯联苯吸附起主要作用,土壤更易吸附高氯代PCB77;黏土矿物对多氯联苯吸附量大小顺序为:纳米蒙脱石>纳米SiO2>凹凸棒石,黏土矿物吸附多氯联苯能力的大小与黏土矿物的比表面积、粒径、层状结构等有关;多氯联苯本身分子的大小影响其在黏土矿物上的吸附;土壤中添加黏土矿物可以提高对多氯联苯的吸附。 相似文献
13.
探明反射光谱估算土壤黏粒含量的成因是实现黏粒含量测定、提高估算精度的基础。该文以江苏省滨海平原的150个土壤样品为研究对象,将测得的原始光谱数据进行平滑、一阶导数、连续统去除和倒数等数据变换,采用逐步多元线性回归(stepwise multiple linear regression,SMLR)和偏最小二乘回归(partial least squares regression,PLSR)方法估算黏粒含量,并在此基础上分析建模的影响波段,探讨反射光谱估算土壤黏粒含量的成因。结果表明,连续统去除光谱数据的SMLR分析估算精度最高,建模集和验证集决定系数分别为0.941和0.750。360~900、1 800~2 490 nm是黏粒含量的重要建模影响波段,该建模影响波段主要包括铁离子(410 nm附近)、土壤有机质(500~800 nm)、层状硅酸盐中的结晶水(1 900 nm附近)、绿泥石和蛭石等黏土矿物(2 325 nm)的吸收特征波段;PLSR分析表明,1 400 nm附近回归系数出现的双峰特征源于高岭石的双峰吸收。黏粒中的黏土矿物、黏粒对铁离子的吸附特性以及黏粒与有机质的高度相关性是实现反射光谱估算滨海土壤黏粒含量的原因。 相似文献
14.
B. Mueller 《土壤圈》2015,25(6):799-810
Interactions between microbes and minerals have the potential to contribute significantly to global cycles of various processes and serve as a link between the geosphere and life. Clays and clay minerals occur commonly in agriculturally utilized soils, are naturally grown underground (soil and rock) and are used in construction material. Clay minerals serve as natural, geological and technical barriers in geotechnics and environmental geotechnics. Bacteria in turn are ubiquitous in natural soils, subsoils and rocks and are in permanent contact with clay minerals. There are numerous ways in which bacteria can interact with clay minerals and alter them: dissolution, refinement and transformation, reduction of trace elements incorporated in the clay minerals and uptake of trace elements from these minerals, e.g., by the production of siderophores and chelators and enhancement or reduction of adsorbance of trace elements on clay minerals. In addition, bacteria can influence layer charge, cation exchange capacity (CEC), exchangeable cations, Brunauer-Emmett-Teller surface, swelling and the rheological properties of clay minerals. The field of clay mineral-microorganism interaction is still wide open because of the large potential that the interactions of bacteria with clay minerals in soils and sediments may result in changes in clay mineral properties and behaviors. Further detailed studies on all these tentative changes and underlying mechanisms as well as broad surveys of quantifications of extents and rates of clay mineral-microorganism interactions, especially in mimicking natural systems, are highly required. This review summarizes the influences of various bacteria on the properties of different clay minerals as determined experimentally using viable bacteria. 相似文献
15.
解钾细菌与黏土矿物协同促进玉米生长提高土壤养分有效性 总被引：3，自引：1，他引：2
为了揭示解钾细菌在西北矿区浅埋古河道土壤中对植物生长和土壤养分利用的影响,通过日光温室短期盆栽的方式,以不同黏土矿物配比的人工培土为基质模拟古河道不同质地土壤,以西北地区常见农作物玉米为宿主,研究解钾细菌在人工培土基质中的微生物数量变化规律,以及二者协同作用对玉米生长和矿质养分吸收的影响。结果表明:1)土壤黏土矿物含量增大有利于提高土壤解钾细菌数量,促进微生物活性。当黏土矿物质量分数为68%,速效钾质量分数约170 mg/kg时,解钾细菌数量最大;2)玉米地上部分干质量、根冠比、根系活力随黏土矿物含量增大而增大,以解钾细菌作用下黏土矿物质量分数68%的玉米生长效果最佳;3)在解钾细菌作用下,植物氮磷钾积累量和土壤养分利用的最佳土壤黏土矿物质量分数为45%、68%和75%,土壤钾素、氮素和磷素最大利用率分别达到65%、53%和17%;4)解钾细菌在土壤钾素含量低时促进土壤磷素吸收,土壤钾素过量时,促进土壤氮磷钾的吸收,提高土壤养分利用率。因此,土壤黏土矿物与解钾细菌相互作用,而且积极影响植物生长和土壤养分的吸收利用,这对进一步探寻适合矿区浅埋古河道土壤的微生物复垦技术,深入改良和开发矿区退化土壤具有重要意义。 相似文献
16.
17.
Towada Ando soils consisted of five soils—Towada-a (1,000 years old), Towada-b (2,000 years old), Chuseri (4,000 years old), Nanbu (8,600 years old), and Ninokura soils (10,000 years Amorphous clay materials of these soils taken at different localities were studied by the combined use of selective dissolution and differential infrared spectroscopy, X-ray analysis, electron microscopy, etc. The main clay minerals of Towada-a soils, present-day soils, were montmorillonite-vermic-ulite chloritic intergrades and opaline silica, or these minerals and allophane in the humus horizons, and allophane in the non-humus ones. Towada-b soils overlain by the Towada-a soils showed the clay mineralogical constituents similar to those of Towada-a soils. However, allophane was one of the main clay minerals in all the humus horizons as well as non-humus ones. The main clay minerals of Chuseri soils were allophane and layer silicates consisting chiefly of chloritic intergrades and chlorite in the humus horizons, and allophane in the non-humus ones. Opaline silica was present in minor amounts in the humus horizons of Chuseri soils, but nearly absent in Nanbu and Ninokura soils. There were remarkable differences in the clay mineralogical composition of Nanbu and Ninokura soils with differences of their environmental conditions. Allophane and imogolite Were dominant in the clay fractions of both humus and non-humus horizons of very shallowly buried Nanbu soil which was subjected to the strong leaching process. Allophane was the main clay mineral of deeply buried Nanbu and Ninokura soils which showed the absence of notable accumulation of bases and silica. On the contrary, halloysite with a small amount of siliceous amorphous material appeared in very deeply buried Nanbu and Ninokura soils where bases and silica were distinctly accumulated. The amounts of halloysite in the clay fractions were larger in the humus horizons than non-humus ones, and in Ninokura soil than Nanbu soil. Soil age, soil organic matter, and depositional overburden of tephras were observed to be conspicuous among various factors relating to the weathering of amorphous clay materials in Towada Ando soils. 相似文献
18.
In the preceding paper (1), the authors had determined the infrared absorption spectra of humic acids obtained from various soils of different origin, and concluded that they were, according to their infrared characteristics, classified into four groupes, i.e., A,B,Rp, and P types. After that, the authors conducted some experiments of the infrared spectra of soil components in order to get some information on the nature of so-called humin, and forms of soil clay and clay humus complex. The infrared spectra of silica, sesquioxides, clay minerals and humates of aluminium, iron and calcium were also determined for comparison. These experimental results will be given in this paper. 相似文献
19.
《Communications in Soil Science and Plant Analysis》2012,43(17-18):2721-2733
Availability of applied potassium (K) as a fertilizer to plants is influenced by soil mineralogy, environmental factors, and rates of K application. The objective of this research was to study the effects of clay minerals and K application on K supply characteristics of calcareous soils in Iran. Surface and subsurface horizons of six sites with different ranges of clay content and exchangeable K were selected. The soils were treated with potassium chloride (KCl) solution with different K concentrations. Four wet–dry cycles were sequentially applied. Illites, vermiculites, and chlorites were present in all soils. Smectites were present in larger amounts in one soil. The increase in soluble and exchangeable K was expressed by linear equations in which the slops influenced by the dominant clay minerals. Potassium fixation was much higher in soils with more illites and vermiculites. Results revealed that different forms of K were affected by the dominant clay minerals but were independent from the rate of applied K. 相似文献
20.
In the course of chemical weathering, rockforming minerals release constituent ions changing into secondary minerals by alteration or recrystallization. Minerals formed in this way are primarily of colloidal nature, and are the most active portion in soils together with humus. The chemical weathering has dual meaning for soil fertility, that is, it provides soils with nutrients released and inorganic colloids formed, namely clay minerals. It has been well established that climate, vegetation, parent material, topography and time influence the formation of soils. Generally speaking, Japanese soils have developed under a warm and humid climate which causes leaching of released bases resulting in acid reactions, and a predominance of kaolin in soils. Accumulated information pertaining to Japanese soils, however, has disclosed that physical, chemical, and mineralogical properties of parent rocks are still obviously reflected in the clay minerals of soils. 相似文献