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1.
高效栽培雷竹林土壤重金属含量的分析研究 总被引：16，自引：0，他引：16
雷竹(Phyllostachyspraecox)是最近十几年发展起来的优良笋用竹种,近年来以重施肥和冬季地表覆盖增温为核心的高效栽培技术在生产上得到了大面积推广。为了解高效栽培雷竹林土壤重金属含量现状,采集了浙江省雷竹主产区40个样点土壤样品,利用ICP法分析了土壤重金属含量。结果表明,雷竹林土壤重金属镉(Cd)、铬(Cr)、铜(Cu)、铅(Pb)和锌(Zn)全量含量分别为0.23±0.11,68.23±25.61,23.26±6.61,12.47±2.86,108.50±54.92mg/kg,所有样点5种重金属全量均未出现超标现象。Cd、Cr、Cu、Pb和Zn有效态含量分别为0.028±0.025,0.150±0.102,3.482±1.304,1.636±1.022,10.814±9.767mg/kg,5种重金属有效态含量变异均明显大于全量。重金属Cd、Cu、Pb和Zn有效态含量占全量百分比较高。从不同栽培历史雷竹土壤重金属含量变化来看,Cu、Pb、Zn3种元素随着栽培历史延长,土壤中全量含量显著上升,其中Cu上升量最大,栽培历史从2～3年延长到8～10年,Cu含量增加了1.39倍。重金属Cd、Cu、Zn全量与有效态含量间具有显著或极显著相关性。 相似文献
2.
北京市五环内绿地土壤4种重金属的形态特征及其生物有效性 总被引：4，自引：0，他引：4
[目的]了解北京市五环内绿地表层(0—20cm)土壤重金属(Cu,Cd,Pb和Zn)的形态特征及其生物有效性,为北京市绿地土壤重金属污染防治提供比较可靠的参考依据。[方法]在建成时间为2~400a的绿化区内共采集表层土壤样品151个,运用改进BCR提取法分析样品中重金属的赋存形态,而后通过风险评价编码法(RAC)和次生相与原生相分布比值法(RSP)对重金属生物有效性进行评估。[结果]样品中重金属Cu,Cd,Pb和Zn的含量分别为31.42,0.29,29.89,76.78 mg/kg,Cu,Zn在中部和东北部含量较高,Pb在中部地区含量较高,Cd在西北部、东北部和南部存在少量高值区。Cu,Cd,Pb和Zn形态分布的总体规律均为:残渣态可氧化态弱酸溶态可还原态,稳定态含量均远高于有效态,有效态含量比例表明重金属生物有效性大小顺序为:CdZnCuPb风险评价编码法(RAC)表明,Cd和Zn环境风险程度为低风险,Cu和Pb无环境风险。次生相与原生相分布比值法(RSP)显示,Cu,Cd,Pb和Zn元素RSP值分别为0.06,0.49,0.18,0.13,土壤整体上未受到重金属污染,但是有少部分地区存在被污染现象。[结论]北京市五环内绿地土壤总体上不存在重金属Cu,Cd,Pb和Zn污染,环境风险较低,但应对重金属赋存形态保持关注。 相似文献
3.
重庆市城市污泥中的重金属及其农用环境容量 总被引：7，自引：1，他引：6
城市污泥农用的环境风险取决于城市污泥中的污染物含量及土壤理化性质。该文分析了重庆市10个城市污水处理厂污泥中的Cu,Zn,Pb和Cd含量及形态,根据土壤环境容量及氮肥施用量计算了重庆主要旱地土壤的最大施用量和年施用量。结果表明,重庆市城市污泥中的Zn、Cu、Pb和Cd含量分别为362.12～725.32mg/kg,69.84～170.22mg/kg,21.25～107.24mg/kg和1.26～4.25mg/kg。污泥中不稳定态Zn、Cu、Pb和Cd的比例分别为42.89%～44.74%,2.69%～9.45%,0.95%～12.06%和61.05%～79.91%。根据土壤重金属的静态容量,计算出重庆主要旱地土壤紫色土和黄壤城市污泥的一次性最高施用量分别为384.62t/hm2和98.90t/hm2。根据土壤重金属动态容量,以15、20、50为年限,计算出的城市污泥的年施用量,紫色土为66.10,60.91和55.71t/(hm2·a),黄壤为30.32,28.99和27.53t/(hm2·a)。根据作物的需氮量计算城市污泥的年施用量为3.04～6.40t/(hm2·a),该施用量低于根据土壤环境的动态容量计算的施用量,按此用量施用城市污泥更安全。 相似文献
4.
重金属在矿区土壤——蔬菜系统的吸收与迁移特性研究 总被引：1，自引：0，他引：1
《土壤通报》2019,(5):1233-1238
重金属污染土壤的农产品安全倍受大家的关注。研究选择某铅锌矿区周边的蔬菜地,采集叶菜类蔬菜及土壤样品,研究Cd、Pb、Cu、Zn在土壤中的赋存形态及其在土壤-蔬菜系统中的迁移特性。结果表明,污染土壤中Cd、Pb、Zn超标,分别为国家标准限值的1.44～6.44倍、2.97～3.88倍和1.30～2.30倍。BCR连续提取结果显示,Cd、Pb以可还原态为主,Cu、Zn以可还原态和残渣态为主,可还原态Cd、Pb、Cu、Zn分别占总量的70.6%、79.0%、34.4%和38.1%;残渣态Cu、Zn分别占总量的34.6%和30.2%。酸可提取态Zn、Cd分别达13.2%和6.3%。供试蔬菜茎叶中Pb含量超标,为国家标准限值的1.50～5.83倍。蔬菜茎叶中Cd、Pb含量与其土壤中可还原态含量显著正相关,Cd含量与土壤酸可提取态Cd含量显著正相关。蔬菜Cd的富集系数(BCF)相对较高(0.61～3.34),其中水芹和香芹Cd、Pb、Zn的BCF值显著高于其他蔬菜。蔬菜中Zn的迁移系数(TF)较高(0.54～2.07)。叶用芥菜中Cd、Pb、Zn的TF值较高,分别为1.02、2.25、1.62。因此,在污染土壤蔬菜风险评价中需要考虑不同蔬菜品种对重金属吸的吸收迁移特性的差异。 相似文献
5.
赤泥对重金属污染红壤修复效果及其评价 总被引：8，自引：0，他引：8
以赤泥作为原位固定剂,采用盆栽试验从土壤重金属Cd、Pb、Cu、Zn有效态含量,菜心(Brassicaparachinensis)生长及吸收积累Cd、Pb、Cu、Zn含量3个方面探讨不同赤泥用量对重金属污染红壤的固定修复效果,并用毒性淋出试验TCLP法对其生态风险进行评价。结果表明:菜心在未加赤泥的重金属污染土壤中生长受到严重抑制,在加入赤泥的土壤下生长良好,生物产量显著提高,茎叶干重与赤泥量呈二次相关,5.0mg/kg赤泥处理下菜心产量最大。土壤pH值随赤泥用量的增加而升高,二者呈显著正相关。土壤Cd、Pb、Cu、Zn有效态含量均与赤泥用量呈显著负相关关系;与未加赤泥相比,土壤Cd、Pb、Cu、Zn有效态含量降低范围分别为0.9%～34.2%,29.8%～96.8%,59.9%～96.4%,41.1%～92.7%。加入赤泥显著降低菜心茎叶重金属含量,其重金属含量随赤泥用量的增加而降低;与未加赤泥处理相比,茎叶Cd、Pb、Cu、Zn含量降低分别为68.6%～88.6%,87.3%～96.1%,76.6%～80.3%,79.1%～93.3%。2.5mg/kg赤泥处理下土壤生态风险最小。 相似文献
6.
石灰石和海泡石组配对水稻糙米重金属积累的影响 总被引：14，自引：0，他引：14
为了研究组配改良剂(石灰石+海泡石,LS)对于重金属Pb、Cd、Cu和Zn复合污染稻田的修复效果,在湘南某矿区附近稻田中进行了组配改良剂的田间试验。结果表明:施用0~1.8 kg m-2的组配改良剂LS使土壤pH和CEC显著增加,使土壤中Pb、Cd、Cu和Zn交换态含量显著降低。土壤Pb、Cd、Cu和Zn交换态含量的降低是pH升高,土壤胶体的CEC增加及土壤吸附能力增强的共同作用。施用组配改良剂LS显著降低了3个水稻品种(黄华占、丰优9号、Ⅱ优93)糙米中Pb、Cd和Cu的累积量,最大降幅分别为55.8%、66.9%、37.4%,而对糙米中Zn的含量没有明显影响。当LS施用量为1.8 kg m-2时,能使丰优9号糙米中Cd含量(0.195 mg kg-1)达到国家食品中污染物限量标准(0.20 mg kg-1)以下。土壤中交换态Pb、Cd和Cu含量的降低是糙米中重金属累积量减少的原因。土壤交换态Pb、Cd和Cu含量的对数值(lnC交换态)与其糙米中含量(lnC糙米)的对数值之间存在显著的线性相关关系。 相似文献
7.
大宝山矿区农田土壤重金属污染及其植物累积特征 总被引：7，自引：0，他引：7
对金属矿山选冶活动影响的农田土壤,不同灌溉水源会影响重金属的分布累积特征。根据实际情况将大宝山矿区农田土壤分为污水灌溉区、清水灌溉区、自然修复区和对照区,并进行土壤和植物样品采集,调查研究了土壤的基本理化性质,Cd、Pb、Cu、Zn、Mn 5种重金属的含量和化学形态分布,以及不同区域植物中重金属的含量。结果表明:污灌区Cd、Pb、Cu、Zn的含量最高,是自然修复区和清水灌溉区的1.75倍~10.51倍,对照区最低;Mn在各采样点的含量无显著差别。土壤Cd、Cu、Zn、Pb含量两两之间显著正相关,Mn与Cu、Zn、Cd、Pb呈负相关关系;土壤pH与重金属环境有效态关系密切。残渣态是5种重金属的主要存在形态,有机态含量也较高;Cd的环境有效态含量占总量的比例是其他4种重金属的2倍左右。稻米中5种重金属在清水灌溉区的含量均比污水灌溉区低,其中Cu和Zn的含量在两区域均未超标(NY861-2004),而Pb和Cd的含量严重超标。重金属在自然修复区和清水灌溉区呈现较低的土壤污染和人体健康风险,该研究数据可为金属矿区土壤污染控制提供科学的依据。 相似文献
8.
泉州走马埭典型土壤重金属的赋存形态分析 总被引：5，自引：3，他引：2
采用改进的Tessier连续萃取方法研究了泉州走马埭国家农田示范保护区典型土壤中重金属(Cr、Ni、Cu、Zn、Cd、Pb)的化学形态分布,通过土壤重金属的赋存形态分析比较了6种重金属的生物可利用性。研究结果表明,土壤中不同重金属元素化学形态分布具有不同的特点:Cr和Ni主要以残渣态存在,其余形态所占的比例很小;Cu以残渣态含量最高,碳酸盐结合态含量最低;Zn以残渣态为主,可交换态含量最低;Cd以可交换态和碳酸盐结合态为主,水溶态含量最低;Pb以残渣态和铁锰氧化物结合态为主,水溶态含量最低。土壤中除Cd外,Zn、Cu、Cr、Pb、Ni在正常自然条件下相对比较稳定。 相似文献
9.
陕南茶园茶叶品质分析及重金属含量现状评估 总被引：2，自引：1，他引：1
为了解陕南茶园茶叶品质及茶园重金属含量现状,以茶叶主产区为研究对象,采集了8个县区330个茶园土壤样品,测定分析了pH值和铅(Pb)、锌(Zn)、铜(Cu)、铬(Cr)、汞(Hg)、砷(As)、镉(Cd)等7种重金属含量;同时测定分析了33个茶园茶叶品质及茶叶和浸出液中重金属含量。结果表明,茶叶中茶多酚平均含量为25.58%,儿茶素平均总量为20.74%,茶氨酸含量均值为2.45%,游离氨基酸总量均值为4.86%。茶叶中各重金属含量差异较大,Pb为0.04～2.65 mg/kg、Zn为34.82～55.38 mg/kg、Cu为3.18～20.16 mg/kg、Cr为0.09～4.89 mg/kg、Hg为0.02～0.30 mg/kg、As为0.66～1.16mg/kg和Cd为0.02～0.19mg/kg;32茶园茶叶符合《无公害食品茶叶》(NY5244—2004)和NY659—2003标准,33个茶园茶叶Cu含量符合有机茶标准。浸出液中仅检测出Zn、Cu和Cr,平均浸出率分别为:32.65%、24.96%和10.50%。土壤中重金属Pb、Zn、Cu、Cr、Hg、As和Cd的平均含量分别为10.03、87.61、16.42、12.38、0.20、6.89和0.11 mg/kg,综合潜在生态风险指数平均值为95.4,潜在生态风险较低。 相似文献
10.
九华铜矿重金属环境污染状况研究 总被引：1，自引：0，他引：1
选择江苏九华铜矿区,对其周边土壤和作物的重金属污染状况进行了研究.结果发现,约有一半的采样点土壤全Cu含量超过我国土壤环境质量三级标准(400 mg/kg),其DTPA提取态Cu含量的平均值为117 mg/kg.通过对矿区土壤重金属间的相关分析表明,土壤Cu与Zn、Pb、Cd、Co之间呈极显著的正相关关系(p＜0.01),而与Cr、Ni无显著相关,说明了该铜矿区土壤还伴有外源Zn、Pb、Cd、Co的污染.土壤复合污染指数(PI)＞1.0的土壤样品占57.3%.矿区周围作物可食部位Cu、Zn、Pb、Cd和Cr的含量均较高. 相似文献
11.
Appropriate compost standards are being considered in Canada. Five aspects of compost safety and quality are being evaluated; probably the most controversial aspect is the standards for metals in compost. In order to assist in the development of appropriate standards, the authors began an extensive research project in October, 1993 to determine the bioavailability of metals from compost and compost-metal mixtures. Swiss chard was grown in compost-amended soils or compost in a growth room using five treatments of increasing percentages of compost in the media (0, 25 percent, 50 percent, 75 percent, 100 percent compost (v/v)). A Truro loamy sand and a race-track manure-biosolids compost (RTM-biosolids) supplemented with a high metal biosolids were used in a completely randomized design with five replicates. Dry matter yield, metal content in plant tissue, and total metal uptake were evaluated as well as the total and DTPA-extractable metal content in the compost-soil mixes. The results of this and five other experiments conducted by the authors will help determine whether the suggested limits for As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se and Zn in composts are appropriate. 相似文献
12.
《Communications in Soil Science and Plant Analysis》2012,43(4):291-301
Abstract The seasonal patterns of foliage nutrient concentrations and contents were monitored for two growing seasons in an 11‐year—old Pinus el1iottii stand. In the first growing season after needle initiation, N, P, K, Mg, and Zn concentrations decreased, but this was followed by an increase in the fall and winter months. Another drop in concentration of all elements, except P, occurred in the second growing season. Decreases in total contents indicated that this drop was a result of translocation to other tissues. In contrast to the mobile elements, the concentration and fascicle contents of Ca, Mn, and Al increased with aging of the needles. Between‐tree variability was least for N, P, and Zn and the N, K, Mg, Mn, and Zn in the current foliage had consistently lower variation than that in the 1‐year‐old foliage. Between‐tree variation for K was lower in the winter than the spring. For pine foliage, recommended sampling period for N, P, Mg, and Zn is mid to late summer and for the other elements it is late fall to late winter. There are several sources of variation that influence the level of nutrients in tree foliage. The most important of these, apart from the tree nutrient status, are seasonal fluctuations, variation between trees, and age of needles . Smaller sources of variation are associated with position of the needles within the crown, diurnal changes, year to year variation, and analytical errors1,2. These variables must be studied in order to develop suitable sampling techniques and in Pinus this has been undertaken for P. banksiana 1, P. taeda 3, P. strobus 4, P. resinosa 4, P. sylvestris 5, and P. radiata 6,7. However, foliage sampling has not been studied in detail for slash pine (Pinus elliottii Englem var. elliottii) and earlier studies with other pines have been largely confined to temperate or cool climates. This study reports the variation in elemental concentrations with season, age of foliage, and between slash pine trees growing in a subtropical climate in Florida. 相似文献
13.
14.
《Communications in Soil Science and Plant Analysis》2012,43(9):751-756
Abstract The phytotoxicity of five nonessential elements (Co, V, Ti, Ag, Cr) to higher plants was studied in solution culture experiments with bush beans (Phaseolus vulgaris L. C.V. Improved Tendergreen). All, but in varying degrees, tended to concentrate in roots with a decreasing gradient to stems and leaves. Cobalt was one of the more mobile of the five trace metals. Its toxicity was expressed as severe chlorosis; 43 (with 10‐5 M) and 142 (with 10‐4 M) μg Co/g dry weight in leaves resulted in severe chlorosis. Vanadium as 10‐4 M vanadate resulted in smaller plants but not in chlorosis. Leaf, stem, and root V, respectively, were 13, 8, and 881 μg/g dry weight. Titanium was somewhat mobile with considerable yield decrease at 10‐4 M; leaf, stem, and root Ti concentrations, respectively, were 202, 48, and 2420 μg/g. Symptoms were chlorosis, necrotic spots on leaves, and stunting. Silver was very lethal at 10‐4 M AgNO3; at 10‐5 M yields were greatly decreased, but plants were grown without symptoms. Leaf, stem, and root concentrations of Ag for this treatment, respectively, were 5.8, 5.1, and 1760 μg/g dry weight. Plants grown with 10‐5 N Cr2O7 were decreased in yield by about 25% with or without EDTA (ethylenediamine tetraacetic acid) while the same level of Cr2(SO4)3 was essentially without effect. For the two salts, the leaf, stem, root concentrations for Cr, respectively were 2.2 and 1.3, 0.7 and 0. 7, and 140 and 104 μg/g. Most of the trace metals studied here had interactions in the uptake and/or distribution of other elements. 相似文献
15.
A Gimeno 《Journal of the Association of Official Analytical Chemists》1979,62(3):579-585
A general method is described for determining 16 mycotoxins in mixed feeds and other food products used in the manufacture of these feedstuffs. The mycotoxins are extracted and cleaned up by extracting with solvents of different pH. Thin layer chromatography is used to separate the toxins; toxins are then quantitated by the limit detection method. The minimum detectable concentration of mycotoxins in various products is: aflatoxin B1 or G1, 4--5 micrograms/kg; ochratoxin A or ethyl ester A 140--145 micrograms/kg; citrinin 600--750 micrograms/kg; zearalenone, 410--500 micrograms/kg; sterigmatocystin, 140--145 micrograms/kg; diacetoxyscirpenol, 2400--2600 micrograms/kg; T-2 toxin, 800--950 micrograms/kg; patulin, 750--800 micrograms/kg; penitrem A 14,000--14,500 micrograms/kg; penicillic acid 3400--3650 micrograms/kg. 相似文献
16.
B S Kaphalia R Takroo S Mehrotra U Nigam T D Seth 《Journal of the Association of Official Analytical Chemists》1990,73(4):509-512
A total of 244 samples of cereals (wheat flour, rice, and maize), pulses (arhar, moong, gram, lentil, and black gram), spices (turmeric, chili, coriander, and black pepper), vegetables (potato, onion, spinach, cabbage, brinjal, and tomato), fruits (mango, guava, apple, and grape), milk, butter, Deshi ghee, and edible oils (vegetable, mustard, groundnut, and sesame) collected from different cities of Northern Province (Utter Pradesh) were analyzed by gas liquid chromatography for the presence of organochlorine pesticide residues. Residues of hexachlorocyclohexane (HCH) and 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) were detected in about 85% of the total samples of cereals, spices, milk, butter, Deshi ghee, and edible oils analyzed in the present study. However, the residue levels were either very small (less than 0.06 ppm) or not detected at all in pulses, vegetables, and fruits as compared with very high concentrations in wheat flour (4.42 and 0.12 ppm), butter (1.19 and 4.85 ppm), mustard oil (1.26 and 2.42 ppm), Deshi ghee (1.10 and 3.84 ppm), vegetable oil (1.02 and 0.59 ppm), groundnut oil (0.51 and 1.49 ppm), and chili (0.48 and 1.92 ppm). The levels of HCH and DDT residues detected in rice, maize, turmeric, corlander, black pepper, and all the vegetables and fruits were also lower than those found in wheat flour, oil, and fat samples analyzed in the present study. These findings suggest that a restricted and controlled use of such persistent pesticides may be useful for decreasing their contamination levels in different food items. 相似文献
17.
《Communications in Soil Science and Plant Analysis》2012,43(7-8):945-959
Abstract The objectives of this study were 1) to recommend reference values (RVs) and tolerance limits (TLs) for representative Brazilian soils and 2) to propose a model to calculate natural contents of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) in a soil from the silt, clay, manganese (Mn), iron (Fe), and cation exchange capacity (CEC) values. A set of 256 soil samples was classified by similarity in seven groups, and the concentrations corresponding to the upper quarter of data collected were then calculated. These concentrations are proposed as RVs for Brazilian soils. Additionally, TLs were obtained for each group from the antilog expression (m+2s), where m=mean value and s=standard deviation of data transformed in log10. The classification functions of discriminant analysis proved to be suitable to allocate new samples in the established groups. Thus, it is possible to evaluate soils under anthropic activity and, by comparison with reference values, to be aware of pollution risks in a given area. 相似文献
18.
《Communications in Soil Science and Plant Analysis》2012,43(19):2495-2501
Different procedures have been proposed to decompose soil samples. Most of them regard determination with fertility aims. In this case, the contents available to the plants are considered. On the other hand, there are procedures to determine total content. The objective of this work was to propose a new decomposition procedure to determine barium (Ba), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), vanadium (V), and zinc (Zn) total content in tropical soils with high content of oxides and silicate. According to the results, the digestion procedure proposed in this study provided satisfactory results for the contents recovery for the elements Ba, Co, Cr, Cu, Mn, Ni, V, and Zn, above 90%, and the use of inverted aqua regia, hydrogen peroxide (H2O2), hydrofluoric acid (HF), pre-digestions and agitation was shown as a new alternative for the high silicate content soil sample total digestion, such as the oxisols. 相似文献
19.
Nigel J.H. Smith 《Biological conservation》1981,19(3):177-187
Amazonia, the world's largest tropical rain forest, is often assumed to be a virtually untouched wilderness. The region is often referred to as a demographic void; there is on average only about one person per sq. km. Yet in response to international market forces, the hand of man has penetrated deep into the imposing forests. Since colonial times, wildlife, particularly along rivers, has been exploited on a large-scale basis for commercial purposes. This paper focuses on the effects of the trade on some aquatic animals. 相似文献
20.
Rababah TM Hettiarachchy NS Horax R 《Journal of agricultural and food chemistry》2004,52(16):5183-5186
The total phenolics and antioxidant activities of fenugreek, green tea, black tea, grape seed, ginger, rosemary, gotu kola, and ginkgo extracts, vitamin E, and tert-butylhydroquinone, were determined. Grape seed and green tea were analyzed for their phenolic constituents using high-performance liquid chromatography. The total phenolics of the plant extracts, determined by the Folin-Ciocalteu method, ranged from 24.8 to 92.5 mg of chlorogenic acid equivalent/g dry material. The antioxidant activities of methanolic extracts determined by conjugated diene measurement of methyl linoleate were 3.4-86.3%. The antioxidant activity of the extracts using chicken fat by an oxidative stability instrument (4.6-10.2 h of induction time) followed a similar trend in antioxidant activity as determined by the Folin-Ciocalteu method. Seven phenolics in grape seed and green tea extracts were identified that ranged from 15.38 to 1158.49 and 18.3 to 1087.02 mg/100 g of extract, respectively. Plant extracts such as green tea and grape seed extracts can be used to retard lipid oxidation in a variety of food products. 相似文献