污泥农用对土壤和作物重金属累积及作物产量的影响

以3 a定位试验为基础,比较3种不同处理的污泥肥料（消化污泥、污泥堆肥及污泥复混肥）农田施用下土壤养分、土壤和作物籽粒中Mn、Cu、Zn、Pb、Cd 5种重金属的积累以及作物产量的变化情况,以阐明污泥农用对土壤及作物的影响。研究表明,3种污泥肥料提高了土壤中氮素和有机质的含量;与空白和普通化肥处理相比,3种污泥肥料增加了土壤中Mn和Cu的含量,而对土壤交换态重金属含量没有显著影响;3种污泥处理均增加了小麦籽粒中Zn的含量;相对普通化肥处理,3种污泥肥料处理对小麦和玉米产量均无显著影响。合理施用污泥肥料可以有效地提高作物产量;污泥肥料施用对土壤重金属有一定累积效应,但短期施用对土壤比较安全。     

Assessment of Heavy Metals in Spinach (Spinacia oleracea L.) Grown in Sewage Sludge–Amended Soil

The assessment of heavy metals in spinach (Spinacia oleracea) grown in sewage sludge–amended soil was investigated. The results revealed that sewage sludge significantly (P < 0.01) increased the nutrients and heavy metals such as cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), and zinc (Zn) in the soil. The contents of metals were found to be below the maximum levels permitted for soils in India. The most agronomic performance and biochemical components of S. oleracea were found at 50% concentrations of sewage sludge in both seasons. The contents of Cd, Cr, Cu, Mn, and Zn in S. oleracea were increased from 5% to 100% concentrations of sewage sludge in both seasons. The order of contamination factor (Cf) of different heavy metals was Mn > Cd > Cr > Zn > Cu for soil and Cr > Cd > Mn > Zn > Cu for S. oleracea plants after application of sewage sludge. Therefore, use of sewage sludge increased concentrations of heavy metals in soil and S. oleracea.     

珠江三角洲污灌区土壤中重金属含量特征

通过现场采样及室内测试方法,分析了珠江三角洲污灌区土壤中9种重金属Cd、Cu、Zn、Pb、Mn、Ni、As、Cr、Se的含量分布特征。结果表明,污灌区土壤9种重金属的全量平均含量均已超出广东省土壤背景值,其中Cd的污染程度最重,Se的污染程度最轻;污灌区土壤以Cd元素的有效系数最高,Ni元素的有效系数最低。Zn、Pb、Cu以及Cd元素随采样深度的增加其全量逐渐减少,Cr、Ni、As以及Se元素随采样深度的增加其全量呈上下波动状态或几乎不变,而Mn元素则是随采样深度的增加其全量先略有减少而后骤升。Cu、Cd、Zn等3种元素全量与有效态含量以及这3种元素全量间均呈显著或极显著的正相关关系。     

Long-term changes in soil and plant metal concentrations in an acidic dredge disposal site receiving sewage sludge

A long-term experiment was conducted to determine the distribution of sludge-borne metals applied to a revegetated acidic dredge spoil disposal site. The initial soil was infertile and highly acidic (pH 2.4). Sewage sludge and lime were applied in 1974 at the rates of 100 and 23 mt ha^?1, respectively, and tilled into the soil to a depth of 20 cm. In 1974 an adjacent site was also revegetated with topsoil and lime but without sludge. Soil and plants were sampled 2, 4 and 16 yr following seeding. After 16 yr the total and DTPA-extractable Cu, Zn, Cr, Pb, Ni and Cd decreased in soils to nearly the levels of the control soils. Concentrations of metals in plants also decreased. Decreases in tissue concentrations ranged from 40 to 70% for Cu, Cr, Pb, Ni and Cd and up to 90% for Zn. The results showed that a single 100 mt ha^?1 application of sewage sludge containing high concentrations of metals was a cost-effective method for improving plant growing conditions on highly acidic soils.

     

生活污泥对滩涂土壤性质和苏丹草生长及重金属累积的影响

滩涂盐土农业利用的主要障碍是盐分含量过高和缺乏有机质。施用生活污泥可快速提高滩涂土壤有机质含量,加快土壤熟化,但由于担心污泥含有一定量的重金属,其施用受到一定的限制。采用盆栽苏丹草的试验方法,研究滩涂盐土施用不同量的生活污泥后对土壤性质、植物生长和对重金属累积的影响。结果表明,生活污泥施用于滩涂盐土后降低了土壤pH值,提高了EC值和总盐含量;苏丹草的出苗率、株高和鲜重增加;施用污泥提高了苏丹草植株中全氮、全磷及叶绿素的含量,且随施用量的增加而增大,但对植株中全钾的含量无显著影响;苏丹草中Zn、Cd含量随着污泥施用量增加呈增长的趋势,但Pb、Ni、Cu含量变化不大。在试验条件下,所施用污泥中重金属向苏丹草体内转移的比例介于0.13%-13.44%之间。就该种土壤而言,要更为注意含Pb量较高的污泥施用,而Cu则是最为安全的。总体考虑,一次性施用干污泥应控制在8t·667m^-2以下。     

兰州市城市污水处理厂污泥中重金属形态分布特征与潜在生态风险评价

通过现场调查采样及室内分析,研究了兰州市七里河安宁污水处理厂和雁儿湾污水处理厂污泥中重金属的形态分布特征,并对其进行了潜在生态风险评价。结果表明,污泥总体呈高有机质、高全N和有效P、高微量营养元素,且Cu、Zn、Cd、Pb、Ni5种重金属的含量均低于污泥农用控制标准,具有很好的农用价值。污泥中Zn、Cd、Pb主要以有机结合态和残渣态存在,而Cu、Ni可交换态所占比例较高,分别为14.95%和14.41%,不稳定态所占比例分别为41.12%和31.04%,表现出较高的生物活性和可利用性。七里河和雁儿湾污泥中重金属的潜在生态风险属于低度风险;Cd、Cu是污泥中重金属潜在生态风险的主要贡献者,在污泥处理处置时应引起高度重视。     

Assessment of the interactions of metals and nitrilotriacetic acid in soil/sludge mixtures

The solution phase forms of Cu, Mn, Ni, and Zn in digested sewage sludge and a soil/sludge mixture were investigated. Gel filtration chromatographic analysis indicated that Cu and possibly Ni were maintained in solution by association with a soluble, high molecular weight organic fraction; Mn solubility was due to the presence of unbound inorganic species and soluble Zn was distributed equally between the two forms. Speciation of the metals in the solution phase of the soil/sludge mixture generally reflected that of the sludge. However, the total amount of soluble Mn in the soil/sludge mixture was approximately 25 times greater than in the sludge and was attributed to heavy metal induced release of indigenous soil Mn. Increases in the quantities of soluble Ni and Zn in both the sludge and the soil/sludge mixture following equilibration with 40 mg L^?1 NTA were due to conversion of solid phase forms to soluble metal-NTA complexes. The preferential complexation of NTA with Cu already present in soluble organic forms resulted in a change in speciation without a corresponding increase in solubility. The importance of changes in speciation with regard to potential metal mobility and bioavailability within sludge-amended soil is discussed.     

剩余污泥厌氧消化过程重金属形态转化及生物有效性分析

为研究污泥厌氧消化过程中物理化学性质的变化对典型重金属形态转化的影响,对其农用的可行性及生物有效性进行评估,对取自某城市污水处理厂的剩余污泥进行了序批式厌氧消化实验,在试验过程中测定了污泥理化学性质,采用Tessier分步提取法提取了污泥样品中的典型重金属,并采用电感耦合等离子发射光谱仪（ICP-OES）测定各形态重金属含量及总量。结果表明,厌氧消化过程中重金属的形态发生了显著变化,由不稳定态向比较稳定的残渣态和有机结合态转变,某些重金属形态与污泥理化性质如pH、碱度、VS/TS及氨氮显著相关。厌氧消化可以有效地降低污泥中重金属的潜在迁移能力和生物有效性,经厌氧消化后污泥可以更好地进行土地利用。     

城市污泥与花生壳制活性炭的重金属形态分析及生态风险评价

采用BCR提取法对以污泥和花生壳为原料制备的活性炭进行重金属形态分析,利用原子吸收法测定污泥热解前后Cd、Cr、Cu、Zn、Ni、Pb的不同形态含量。结果表明,污泥中Zn的含量最高,Zn和Cu的含量超过了污泥农用标准。热解可使污泥中的可溶解态和可还原态重金属转化为性质稳定的残渣态重金属,在此基础上,利用重金属潜在生态风险指数法（IR）对污泥活性炭的重金属潜在生态风险进行评价,结果得出花生壳添加量为20%,热解温度为600℃条件下,制备出来的活性炭风险最小。同时证实Cd的潜在生态风险系数较大,在利用时应引起足够的重视。     

污泥污水在棉花上的施用: Ⅰ.对土壤性质的影响

A field experiment with cotton was conducted on a well drained,calcareous,clay loamy Typic Xerochreph to investigate the utility of sewage sludge as a partial substitute for fertilizers and the influence of tis application on the basic soil properties and heavy metal concentrations.The experimental design was completely randomized blocks with five treatments replicated four times each.Sewage sludge came from the treatment plant of the municipality of Volos,Central Greece,with the following characteristics:organic matter content 36.6%,pH(H2O1:5)6.89,CaCO3 53.4g kg^-1,total N 265.g kg^-1,ttal P33.5g kg^-1,and total K 968mg kg^-1 soil.Heavy metal concentrations were Cd 5.24,Pb 442,Ni38,Cu 224,Zn1812,and Mn 260mgkg^-1 dry weight,respectively.The soil was high in potassium(K)and poor in available phosphorus(P).The results showed that sewage sludge application increased cotton yield and K and P concentrations in cotton leaves,Soil pH was reduced in the case of higher sewage sludge rate.Electrical conductivity,organic matter content,totalN,and avaiable P were significantly increased.Total concentrations of Zn,Pb,and Cu were slightly increased.DTPA-extractable Zn,Cu,and Mn were also significantly increased.Available forms of all heavy metals,except Cd,were significantly correlated with organic matter content in a positive way and negatively with soil pH.     

Pollution and Ecological Risk Assessment of Heavy Metals in Farmland Soils in Yanqi County,Xinjiang, Northwest China

A total of 50 farmland soil samples were collected from the Yanqi County, Xinjiang, China, and the concentrations of eight heavy metal elements (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined by standard methods. The spatial distribution, pollution level and ecological risk status of heavy metals were analyzed based on GIS technology, the Geo-accumulation Index (Igeo), the Pollution Load Index (PLI) and the Potential Ecological Risk Index (RI). Results indicated that: (1) The average contents of Cd, Cr, Ni, Pb, and Zn of farmland soils exceeded the background values of irrigation soils in Xinjiang by 1.5, 1.40, 1.33, 2.63, and 4.92 times, respectively. Cd showed a no-pollution level, Zn showed a partially moderate pollution level, Pb showed a slight pollution level, and Cr, Cu, As, Mn, and Ni showed no-pollution level, compared to the classification standard. The PLI values of heavy metal elements of farmland soils varied from 0.83 to 1.89, with an average value of 1.29, at the moderate pollution level. (2) The Individual Potential Ecological Risk Index for heavy metals in the study area was ranked in the order of: As > Ni > Cu > Cd > Pb > Cr> Zn. The RI values of heavy metals of farmland soils varied from 3.45 to 11.34, with an average value of 6.13, at the low ecological risk level. (3) Cu and Mn of farmland soils were mainly originated from the soil parent material and topography of the study area. As, Cd, Ni and Pb were mainly originated from human activities, and Cr and Zn may originated from both natural and anthropogenic factors in the study area.     

蚯蚓活动对城市生活污泥重金属的影响

采用塑料温棚内垄式堆积污泥培养蚯蚓方式,研究了蚯蚓处理对污泥重金属的影响。结果表明,污泥经蚯蚓处理后,理化性质发生了显著的变化,污泥的pH值、有机质、总氮和总磷都有不同程度的降低;蚯蚓能吸收富集污泥中的重金属,其中对重金属Cd有较强的富集能力;蚯蚓处理使污泥中重金属含量均出现不同程度的下降,重金属Cr、Zn、Pb、Cd、Cu、Ni分别减少27.98%、31.46%、32.81%、13.85%、23.86%和22.92%。利用盆栽试验,研究了污泥施用于土壤后生菜体内重金属积累的情况,结果表明,生菜体内重金属Zn、Cu、Pb和Ni的含量为污泥处理高于蚓粪处理;Cr和Cd则分别为差异不显著和略有降低。     

Extractability and plant uptake of heavy metals in alum shale soils

Abstract

Fifty soil samples (0–20 cm) with corresponding numbers of grain, potatoes, cabbage, and cauliflower crops were collected from soils developed on alum shale materials in Southeastern Norway to investigate the availability of [cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), and manganese (Mn)] in the soil and the uptake of the metals by these crops. Both total (aqua regia soluble) and extractable [ammonium nitrate (NH₄NO₃) and DTPA] concentrations of metals in the soils were studied. The total concentration of all the heavy metals in the soils were higher compared to other soils found in this region. Forty‐four percent of the soil samples had higher Cd concentration than the limit for application of sewage sludge, whereas the corresponding values for Ni, Cu, and Zn were 60%, 38%, and 16%, respectively. About 70% the soil samples had a too high concentration of one or more of the heavy metals in relation to the limit for application of sewage sludge. Cadmium was the most soluble of the heavy metals, implying that it is more bioavailable than the other non‐essential metals, Pb and Ni. The total (aqua regia soluble) concentrations of Cd, Cu, Zn, and Ni and the concentrations of DTPA‐extractable Cd and Ni were significantly higher in the loam soils than in the sandy loam soils. The amount of NH₄NCyextractable metals did not differ between the texture classes. The concentrations of DTPA‐extractable metals were positively and significantly correlated with the total concentrations of the same metals. Ammonium nitrate‐extractable metals, on the other hand, were not related to their total concentrations, but they were negatively and significantly correlated to soil pH. The average concentration of Cd (0.1 mg kg^‐1 d.w.) in the plants was relatively high compared to the concentration previously found in plants grown on the other soils. The concentrations of the other heavy metals Cu, Zn, Mn, Ni, and Pb in the plants were considered to be within the normal range, except for some samples with relatively high concentrations of Ni and Mn (0–11.1 and 3.5 to 167 mg kg‘¹ d.w., respectively). The concentrations of Cd, Cu, Zn, Ni, and Mn in grain were positively correlated to the concentrations of these respective metals in the soil extracted by NH₄NO₃. The plant concentrations were negatively correlated to pH. The DTPA‐extractable levels were not correlated with plant concentration and hence DTPA would not be a good extractant for determining plant availability in these soils.     

Temporal variation of total and DTPA-extractable heavy metal contents as influenced by sewage sludge and perlite in a calcareous soil

Continuous application of sewage sludge (SS) as a source of organic matter, may increase available heavy metals (HMs) up to their critical levels. As a consequence their uptake by plants, risks of accumulation in food chain and groundwater pollution increases. To evaluate the effects of perlite and SS on total content and available fraction of iron (Fe), manganese (Mn), lead (Pb), copper (Cu), nickel (Ni), cadmium (Cd) and zinc (Zn) over 45 and 90 days a completely randomized pot experiment was conducted. Treatments consisted of SS (0, 2 and 4%) and combined SS and perlite levels (1:1, 1.5:0.5 and 0.5:1.5% SS:perlite). Mean available Fe, Ni, Cd, Mn and Zn fractions decreased over time by 7–27%, whereas, total contents did not change. Available HMs in SS-treated soils increased by 0.5–25%; whereas, only total Zn, Cu and Pb concentrations increased with SS application (although concentrations fall in the range of critical levels). The lowest (1.6 fold) and highest (22.1 fold) increases obtained for available Cu and Zn, respectively. Perlite could mitigate the adverse effect of high rate application of SS on amplification of HMs extractability. Therefore, their concomitant applications can be suggested considering the perlite durability and its positive effects on soil physical properties.     

蚯蚓对造纸污泥的养分和重金属处理效应研究

造纸污泥含有大量的养分和重金属等物质。试验采用室内培养试验,研究不同蚯蚓投放量对污泥中养分和重金属的处理效应。结果表明:蚯蚓的最佳投放量为中等投放量(22.5 g kg-1)。经过84天处理后,造纸污泥中有机质大量分解,最高分解率为24.95%;全量N、P、K的含量增加,其最大增量分别为2.65 g kg-1、0.64 g kg-1和0.32 g kg-1;碱解氮、速效磷、速效钾的最大减幅依次为24.78%、30.40%和10.77%。经蚯蚓处理后造纸污泥中重金属Mn、Cu和Zn的最大去除率依次为28.80%、28.80%和35.34%,蚯蚓体内Mn、Cu和Zn最高增加了8.03%、23.49%和27.06%,Mn、Cu和Zn的K值均小于1.0,其中Mn>Zn>Cu,说明蚯蚓对重金属Mn、Cu和Zn有明显的去除效应。     

Application of composted sewage sludges contaminated with heavy metals to an agricultural soil

To elucidate the mechanism of transfer of heavy metals into the food chain, an experiment was carried out with a calcareous soil, to which two different doses of a sewage sludge compost contaminated with either Cd or Zn, Cd, Cu, and Ni were applied. A crop of lettuce was then grown in the amended soils. The application of sewage sludge composts to a calcareous soil lowered the soil's pH, although the value was always around 8 at the end of the experiment. Electric conductivity rose with organic amendment. As anticipated, such an amendment improved the nutritional level of the soils, particularly Nand P, both total and available. Plant yields were negatively affected by organic amendments contaminated with heavy metals, the most dangerous in our experiment being Cd and Zn since this metals easily taken up by plants. As Ni and Cu form insoluble complexes with the organic matter of the sewage sludge composts they are not readily absorbed. Of the metals studied, Cd and Zn showed the highest bioavailability index.     

基于多元统计和地统计的肇源县表层土壤重金属来源辨析

土壤圈是地圈系统中对人类健康影响最显著的圈层之一。土壤重金属的自然和人为来源辨析对土壤修复和保障人体健康有重要意义。本研究以黑龙江省肇源县为研究区域,通过空间插值分析、主成分分析和聚类分析等方法,对区域土壤表层和深层土壤重金属As、Hg、Cd、Cr、Cu、Ni、Zn的含量和空间分异特征进行分析,进而对区域表层土壤重金属来源进行辨析。结果表明:成土母质作为表层土壤的重要物质来源对表层土壤重金属含量及空间分布有显著影响;肇源县表层土壤中Hg元素表现出全局范围较明显的富集现象,局部区域Cd元素表现出一定的富集现象,富集原因是人为污染造成的;嫩江上游汇水区土壤重金属元素的迁入,是表层土壤重金属As、Cd、Cr、Cu、Ni、Zn等元素在研究区范围内轻度富集的主要原因。     

中国五个典型城市污水厂污泥中重金属的形态分布研究

Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR （Community Bureau of Reference） sequential extraction procedure. The sludges contained considerable amounts of organic matter （31.8%- 48.0%）, total N （16.3-26.4 g kg^-1） and total P （15.1-23.9 g kg^-1）, indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China＇s control standards for pollutants in sludges from agricultural use （GB 4284-1984）. The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.     

大宝山矿区农田土壤重金属污染及其植物累积特征

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。     

Chemical extractability and availability of heavy metals after seven years application of organic wastes to a citrus soil

Abstract. The chemical extractability of heavy metals introduced into the soil during 7 years application of sewage sludge, composted municipal solid waste and sheep manure, and their availability to citrus plants were studied. The total content of metals in the soil (0-20 cm)was increased by the use of sludges and compost, but only the Ni content in the saturation extracts of soil was significantly increased. Total Cd, Cr, Cu, Ni, Pb, and Zn were sequentially fractionated into water-soluble plus exchangeable, organically bound, carbonate-associated, and residual fractions. Most of the heavy metals were present in carbonate and residual fractions, although substantial amounts of water-soluble plus exchangeable Cd, and organically bound Cu and Ni were found. No significant increases in the metal contents in leaves and orange fruits were observed, with the exception of Pb in leaves. Several statistically significant correlations between metal content in plants, metal content in soil fractions, and chemical characteristics of soil were also found.