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1.
日光温室菜园土的磷素形态及吸附和解吸特征 总被引:19,自引:1,他引:19
对在斑纹简育湿润淋溶土(潮棕壤)上发育的温室菜园土的磷素含量、磷素的有机和无机组分、磷素的吸附和解吸特征进行了研究,结果表明:日光温室土壤具有明显的磷素积累特征,使用年限在3年~36年日光温室土壤的全磷、速效磷、Cowell全磷和Cowell无机磷含量分别比与其相邻的露地旱田土壤的增加了90.4%~182.4%、505.0%~892.1%、294.5%~478.9%和360.9%~637.6%。其中速效磷含量已达到84.7~138.9mg/kg。日光温室土壤无机磷和有机磷都显著增加,在各组分之间的比例上表现为O-P增加,Ca-P下降,高稳性有机磷相对增加,而活性有机磷所占比例下降。日光温室土壤不仅表现为对磷素的吸附能力增强,而且解吸能力也明显提高。 相似文献
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D. Fernndez‐Calvio B. Garrido‐Rodríguez J. E. Lpez‐Periago M. Paradelo M. Arias‐Estvez 《Land Degradation \u0026amp; Development》2013,24(6):556-563
The aim of this work is to assess the effect of planting patterns on the spatial distribution of total copper and other Cu fractions in vineyard soils. Both classical and geostatistical tools were used for the study. The soil of the plot had a loam texture and was strongly acid. The mean total Cu concentration (CuT) was 368 mg kg−1. The mean value of potential available fractions was 188 mg kg−1 for CuEDTA and 122 mg kg−1 for CuDPTA, whereas the mean exchangeable Cu (CuEX) was 5·2 mg kg−1. All Cu measurements exhibited a wide variation. These values are very high compared with those found in non‐polluted soils, and they can affect the soil, plants and microorganisms. The best correlation for CuEX was with soil pH, whereas for CuEDTA, CuDPTA, and CuT, the best correlation was with soil organic carbon. Directional semivariograms were fitted with a spherical model (parallel to plant rows) and a periodic model (perpendicular) showing a dependence on orientation and distance. All Cu measurements were higher along plant rows than among them, finding a periodic pattern in the variance for the normal direction from plant rows. However, in site‐specific management, it is crucial not only to describe the pattern of variation but also to estimate the Cu content in the soil. Copper concentration maps were estimated by kriging interpolation. These maps show a higher Cu accumulation along the cultivated rows than the uncultivated rows. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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The relation between soil suction, degree of saturation, and the air and water permeabilities is experimentally investigated for two clay soils. Marked hysteresis can exist between saturation and permeability, but does not follow a unique trend. Thus permeability can be greater on a wetting or drying cycle depending on the structure of the clay soil. This behaviour is considered in terms of the cluster concept of soil structure, and it is concluded that any general theory of hysteresis must recognize both the macrostructure and microstructure of a soil. 相似文献
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海南岛土壤粘粒矿物特征与土壤系统分类 总被引:6,自引:0,他引:6
研究了海南岛不同母质土壤的粘粒矿物特征:都含有较多的高岭石,其中玄武岩发育土壤粘粒中高岭石最多,但其结晶最差。片岩和紫色砂岩发育土壤含相当多的水云母,粘粒部分水云母含量高达40%~45%,石灰岩发育土壤水云母含量亦较高,达20%~37%,此类水云母属二八面体型的水化白云母。玄武岩和花岗岩发育的“湿润”土壤粘粒中针铁矿与赤铁矿的含量之比为(3~4):1,而花岗岩发育的“常湿”土壤粘粒中只有针铁矿,不见赤铁矿存在,证明土壤中氧化铁矿物的类型是土壤湿润状况的反应,在中国土壤系统分类中可以用来区分“湿润”和“常湿”土壤的一个指标。 相似文献
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土壤胡敏素各组分数量及结构特征初步研究 总被引:11,自引:2,他引:11
土壤胡敏素(HM)是与矿物质紧密结合的腐殖物质,具有碱不溶性及大分子结构的特性,并呈现不均一性,被认为是土壤中的惰性物质。由于HM的非溶解性和结构复杂性,目前国内外学者对于HM结构特征的研究还很少。对加入大量有机物料培养后新形成的HM数量及性质的研究尚未见报道。本研究选用风沙土、草甸土、黑土、黑土底土加玉米秸秆培养土为材料,根据Pallo分组法,将土壤HM分为铁结合胡敏素(HMi)、粘粒结合胡敏素(HMc)和不溶性胡敏素(HMr)三个组分;对自然土壤中HM各组分以及加入玉米秸秆后新形成的HM各组分的数量及结构特征进行初步研究,为丰富腐殖质化学提供基础性资料。实验结果表明:在自然土壤HM各组分中以HMr为主,其次是HMi,含量最少的是HMc。通过HMi和HMc的光学性质比较得出HMi的分子结构较简单,HMc分子结构相对较复杂,加玉米秸秆培养后新形成的HMi、HMc的分子结构比自然土壤中的简单。红外光谱结果表明,与自然土壤相比加玉米秸秆培养后新形成的HMi、HMc的脂族性最强,自然土壤中HMi、HMc的脂族性强弱顺序为:风沙土〉黑土〉草甸土。 相似文献
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研究了花卉常用的 4种栽培基质 (草炭土、植金石、仙土和含 2 0 %河砂的腐殖土 )对59Fe的吸附及解吸附。结果发现 ,植金石和腐殖土对59Fe吸附最高 ,且土柱上层高于下层 ,其解吸附较少 ,这与土壤的pH值有关 ,pH值高的吸附强 相似文献
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通过间隙淋洗培养试验 ,研究水旱轮作下有机肥与化肥长期配合施用后土壤及不同粒级中氮的矿化特性。结果表明 ,经 14年 2 9茬连续施肥后土壤氮素矿化势明显增加 ,不同处理间的顺序为 :猪粪 化肥 (3 10mgkg- 1) >秸秆 化肥 (2 98mgkg- 1) >化肥 (2 76mgkg- 1) >对照 (2 0 4mgkg- 1)。长期施肥对土壤氮素矿化速率常数影响较小 ,反映了在相同土壤条件下有机氮矿化的共性。经 16周连续培养各处理土壤氮素的矿化率均在 17%左右。土壤不同粒级中氮的矿化量和矿化势均为 0~ 2 μm >2~ 10 μm >50~ 10 0 μm >10~ 50 μm ,有机肥与化肥长期配合施用显著增加了 0~ 2和 2~ 10 μm粒级氮的矿化势和矿化量。与盆栽试验结果相比 ,培养过程矿化释放的氮明显高于同期土壤的供氮量 ,表明在使用矿化氮评价土壤供氮能力时必须加以矫正。 相似文献
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A METHOD OF STUDYING TRACE ELEMENTS IN SOIL FRACTIONS 总被引:1,自引:0,他引:1
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Sand-, silt-, and clay-size organo-mineral fractions were isolated in bulk from surface horizons of five soils following ultrasonic dispersion in water. Good clay separation was achieved for all except one highly organic, calcareous clay soil. Organic-N and -C were concentrated in the clay and silt fractions but for each soil the organic C : N ratio decreased in the order sand > silt > whole soil > clay. Acid hydrolysis of the silt and clay fractions revealed a slight concentration of amino acid-N and NH4-N in the clays but only small differences in the distribution of individual amino acids were observed. The results suggest that both silt and clay fractions may be important in the stabilization of soil organic matter. 相似文献
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对浙江哩铺铜矿尾矿库土壤—海洲香薷 (Elsholtziaharchowensis)植物体系的微生物特征进行了研究。结果表明 :海洲香薷植物中的元素含量表现为Cu >Zn >Pb >Cd ,Cu与土壤元素的相关性最为显著 ,其次为Zn。与对照土壤相比 ,矿区土壤的微生物基础呼吸作用增强 ,但微生物生物量却显著降低 ,微生物生理生态参数Cmic/Corg、qCO2 值明显升高。Biolog结果显示 ,矿区土壤微生物的群落结构发生改变 ,对能源碳的消耗量和速度显著升高 ,但利用效率却明显降低 相似文献
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The adsorption of methylene blue and the accompanying colour change appears to be a fairly specific and sensitive reaction for colloidal soil clay, especially when used with chromatography paper as a supporting medium. Thus minute amounts of clay in migrating soil solutions can be detected, and stability and electro-phoretic mobility of very dilute suspensions evaluated. 相似文献
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长江三角洲地区土壤环境质量与修复研究 Ⅳ.多环芳烃在土壤不同有机质组分中分配特征的研究 总被引:1,自引:0,他引:1
多环芳烃(PAHs)在土壤不同活性有机质库中的分配会影响它们在土壤中的迁移和生物有效性。本研究采用土壤有机无机复合体的分组方法,分离出以游离态有机物质存在的轻组和以有机无机复合体存在的重组,研究了15种美国环境保护署(USEPA)优控的PAHs在土壤轻组和重组以及重组结合态腐殖质不同组分中的分配特征。结果表明,轻组中PAHs总量的含量范围为1.30×104~1.07×105μg kg-1,远远高于PAHs总量的含量为221.7~297.8μg kg-1的重组。土壤中轻组的含量虽然只有0.4%~2.3%,但它结合的PAHs量却占土壤中PAHs总量的31.5%~69.5%。重组中PAHs含量主要分布在紧结态腐殖质中,占重组PAHs总量71.2%~87.2%。结合态腐殖质不同组分中PAHs的含量与它们有机碳的含量呈显著性正相关(p<0.01),紧结态腐殖质对PAHs的富集能力显著高于稳结态和松结态腐殖质。PAHs污染土壤的环境风险可能主要在于轻组结合的PAHs。 相似文献
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硼的吸附-解吸对土壤表面性质的影响 总被引:5,自引:1,他引:5
对三种不同类型土壤———棕红壤、黄棕壤、灰潮土在特定条件下的电荷零点(PZC) :ck—PZC(无硼 )、ads—PZC(硼吸附 )和des—PZC(硼解吸 )的研究发现 ,棕红壤和黄棕壤的ads—PZC与其ck—PZC相比 ,都有较为明显的下降。灰潮土 ,由于本身碳酸盐的缓冲作用 ,其ads—PZC与ck—PZC几乎相等。在硼吸附发生后 ,3种供试土壤的des—PZC较之它们的ads—PZC ,改变甚小 ,但这时灰潮土却保持强劲吸附电位离子的趋势 ,其吸附H 离子数量是棕红壤和黄棕壤的 2倍 ,表明在灰潮土上 ,原先被土壤胶体吸附的硼这时才显示利于电位离子的吸附。研究还表明 ,硼在酸性土壤中的吸附会引起 1 0倍量的质子的吸附 相似文献
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STUDIES ON SOIL COPPER I. THE FRACTIONATION OF COPPER IN SOILS 总被引:3,自引:0,他引:3
A method for fractionating soil copper was developed and applied to 24 soils representing a range of British soil types. The scheme distinguishes five fractions:
- (a) soil solution and exchangeable copper;
- (b) copper weakly bound to specific sites;
- (c) organically bound copper;
- (d) copper occluded by oxide material; and
- (e) residual copper mainly in clay lattice structures.
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土壤粘土矿物反射特性及其在土壤学上的应用 总被引:10,自引:0,他引:10
用实验室测量的埃洛石、蒙脱石、伊利石和蛭石加热处理前后的反射曲线(0.2-2.5pμm),研究上述矿物的反射光谱特征及其与化学组成的关系.提出鉴别主要粘土矿物类型、矿物二、三八面体和根据土壤反射曲线识别主导粘土矿物的方法;并用土壤剖面的反射曲线,解释土壤性状与形成特点. 相似文献