污灌区土壤重金属累积影响因素研究

本文研究了大气沉降、化学肥料施用、污水灌溉3个外源因素对污灌区土壤中重金属Hg、Cd、Pb累积的影响,结果表明:污灌区大气干湿沉降和施肥输入土壤中3种重金属元素的数量顺序为Pb>Cd>Hg。污灌水中重金属Hg、Cd、Pb含量的高低与相对应的灌区土壤中重金属的累积量的多少基本一致,对土壤Cd累积影响最大的是污水灌溉,对土壤Hg累积影响最大的是大气沉降,污灌与大气沉降对土壤Pb累积影响作用相近,施肥对3种重金属元素累积影响最小。     

再生水短期灌溉对土壤-作物中重金属分布影响的试验研究

再生水是农业灌溉的重要水资源。该文在田间小区开展了为期4年的再生水灌溉试验，研究了重金属在土壤-作物系统中的转化与分布规律。结果表明：短期内重金属在土壤中的累积不明显，且土壤和作物籽粒中的重金属含量都远低于国家标准规定的允许值，再生水短期灌溉对土壤环境和作物均不会造成污染影响；同时，不同再生水灌溉水量条件下，土壤中重金属含量无显著差异，再生水灌溉带入土壤中的重金属量小于作物收获所带走的重金属量，带出量和带入量对土壤中重金属平衡的影响较小。     

The transfer of heavy metals to barley plants from soils amended with sewage sludge with different heavy metal burdens

Purpose

Our main aim objective was to evaluate the transfer of Cd, Cr, Cu, Ni, Pb and Zn to barley (Hordeum vulgare) grown in various soils previously amended with two sewage sludges containing different concentrations of heavy metals. This allowed us to examine the transfer of heavv metals to barley roots and shoots and the occurrence of restriction mechanisms as function of soil type and for different heavy metal concentration scenarios.

Material and methods

A greenhouse experiment was performed to evaluate the transfer of heavy metals to barley grown in 36 agricultural soils from different parts of Spain previously amended with a single dose (equivalent to 50 t dry weight ha^?1) of two sewage sludges with contrasting levels of heavy metals (common and spiked sludge: CS and SS).

Results and discussion

In soils amended with CS, heavy metals were transferred to roots in the order (mean values of the bio-concentration ratio in roots, BCF_Roots, in brackets): Cu (2.4)?~?Ni (2.3)?>?Cd (2.1)?>?Zn (1.8)?>?Cr (0.7)?~?Pb (0.6); similar values were found for the soils amended with SS. The mean values of the soil-to-shoot ratio were: Cd (0.44)?~?Zn (0.39)?~?Cu (0.39)?>?Cr (0.20)?>?Ni (0.09)?>?Pb (0.01) for CS-amended soils; Zn (0.24)?>?Cu (0.15)?~?Cd (0.14)?>?Ni (0.05)?~?Cr (0.03)?>?Pb (0.006) for SS-amended soils. Heavy metals were transferred from roots to shoots in the following order (mean values of the ratio concentration of heavy metals in shoots to roots in brackets): Cr (0.33)?>?Zn (0.24)?~?Cd (0.22)?>?Cu (0.19)?>?Ni (0.04)?>?Pb (0.02) for CS-amended soils; Zn (0.14)?>?Cd (0.09)?~?Cu (0.08)?>?Cr (0.05)?>?Ni (0.02)?~?Pb (0.010) for SS-amended soils.

Conclusions

Soils weakly restricted the mobility of heavy metals to roots, plant physiology restricted the transfer of heavy metals from roots to shoots, observing further restriction at high heavy metal loadings, and the transfer of Cd, Cu and Zn from soils to shoots was greater than for Cr, Ni and Pb. Stepwise multiple linear regressions revealed that soils with high sand content allowed greater soil-plant transfer of Cr, Cu, Pb and Zn. For Cd and Ni, soils with low pH and soil organic C, respectively, posed the highest risk.     

污泥和水溶性重金属盐的植物有效性比较研究

采用盆栽方法研究了污泥中重金属的植物有效性,并与等量重金属盐进行了比较。结果表明,施用污泥50 g/kg土和100 g/kg土能明显增加番茄和玉米苗期地上部Zn、Cu、As的含量,对Cr、Ni、Pb含量影响不大。施用污泥可以降低玉米苗期地上部Cd的含量。施用污泥与施用等量水溶性重金属盐比较,污泥重金属有效性低于水溶性重金属盐的有效性。在土壤污泥施用量为50 g/kg时,污泥重金属在番茄苗期的Zn、Cu有效系数分别为80.9%和54.8%;玉米苗期Zn、Cu的有效系数分别为53.4%和70.3%;污泥用量为100 g/kg土时,污泥重金属在玉米苗期的Zn、As有效系数分别为74.5%和64.4%。     

辽宁省污灌区土壤重金属污染特征与生态风险评价

针对当前污灌区土壤污染研究中存在的问题,提出了一种模糊识别模型评价土壤综合环境质量,并对潜在生态风险指数法进行改进,用以计量重金属潜在生态风险。采用建立的方法对辽宁省污灌区土壤环境质量和重金属潜在生态风险进行了评价,结果显示:Cd是辽宁省污灌区首要重金属污染物,而Hg、Pb、Ni污染较为普遍;重金属的来源主要是灌溉污水和农田施肥;以工业废水为灌溉用水的灌区污染情况比以河水为灌溉用水的灌区污染严重;污灌区重金属元素污染程度大小依次为:Cd>Pb>Ni>Hg>Cu>Cr>As,而重金属潜在生态风险从大到小则依次为:Cd>Hg>Pb>Cu>Ni>As>Cr。总体来看,辽宁省污灌区存在一定程度的重金属污染,且具有较为明显的复合型污染特点,其潜在生态风险超出警戒水平,各灌区应根据各自污染特点和风险等级制定相应的污染防治对策。     

Metal accumulation by bermudagrass grown on four diverse soils amended with secondarily treated sewage effluent

Land treatment is increasingly being utilized as a method of waste disposal for both sewage effluent and sludges. While there has been considerable attention directed toward the fate of metallic constituents of sewage sludges, there have been fewer studies of the fate and mobility of metals appled to soils in sewage effluent. This study was undertaken utilizing secondarily treated sewage effluent amended to contain less than 1 mg l^?1 each of Cd, Cu, Ni, Pb, and Zn. The effluent was applied weekly for a period of 1 yr on large undisturbed monoliths of four diverse soils enclosed in lysimeters and sprigged to common bermudagrass (Cynodon dactylon L.). Soil samples were collected periodically and extracted with DTPA to measure plant available metals. Vegetation was harvested, weighed, subsampled and analyzed for total metal content. Total plant uptake of Cd, Cu, Pb, and Ni during the year was less than 1% of that applied. Vegetative uptake of Zn was as high as 2%. Metal uptake was greatest in the soil with the lowest initial pH. Heavy metal concentrations in plant tissue exhibited a cyclic trend. A similar increasing cyclic trend was evident in the DTPA extractable metals in the surface 0 to 12.5 cm of the treated soils. Decreases in plant and DTPA extractable metals occurred when the soils dried, allowing O₂ to enter. Vegetative concentrations of Cd, Cu, and Ni exceeded normal ranges of 0.2 to 0.8, 4 to 15, and 1.0 mg kg^?1, respectively, for vegetation while Pb and Zn were near normal. Only Cd concentration of vegetation posed a threat to grazing animals.     

香薷属植物在重金属修复中的应用进展

香薷属植物应用于重金属修复经历了矿区植物资源调查和比较、室内模拟研究、田间规模修复以及修复后处置研究,已经初步形成一个植物修复技术的完整体系。在现有技术条件下,把生态修复模式、品种驯化及诱导剂"配方"应用到香薷属植物修复土壤重金属污染对提高修复效率具有重要意义。     

奎河污灌区土壤重金属As变化系统动力学分析

污灌污染是一个亟待解决的土壤环境问题,研究污灌区土壤重金属污染状况及其动态对于土壤重金属污染修复具有现实意义。该文以奎河污灌区为例,通过文献资料搜集和现场监测获取相关数据,采用单因子污染指数法和内梅罗综合污染指数法评价了污灌区重金属污染状况,结果表明土壤As轻度污染,水田样点超标率达89.93%,旱地样点超标率达82.39%,水田综合污染指数为1.39,旱地综合污染指数为1.19。以As为例,采用系统动力学方法分析了As含量的变化。结果表明在当前种植制度下,土壤As的消除是一个漫长的过程,需要到2016年土壤As质量分数才会降低到30mg/kg以下,2024年后才会低于25mg/kg,达到当地土壤As背景值更需要到2073年。清除作物秸秆和根系对于消除土壤As污染有益,尤其是远期效果明显,而表层土壤的流失对于土壤As的清除作用显著。     

夏玉米污水灌溉时水分与氮素利用效率的研究

用田间实验研究污水灌溉条件下夏玉米水分与氮素的利用效率。试验设置了高、中、低3个不同灌水水平下的9个对比处理，结果表明：灌水量、灌溉水质、施肥量对夏玉米叶面积指数、株高和产量的影响很小；不同灌溉水量条件下，污水灌溉夏玉米的耗水规律与清水灌溉的耗水规律十分接近，且累积耗水量随灌溉水量的增大而增加；水分利用效率与灌溉水质和施肥无关，仅随灌溉水量的增加而减少。清水灌溉处理玉米的吸氮量高于污水灌溉处理玉米的吸氮量；氮的利用效率与灌水量和施肥无关，仅与灌溉水质有关，且污水灌溉氮的利用效率高于清水灌溉氮的利用效率。     

Arsenic and heavy metal accumulation by Athyrium yokoscense from contaminated soils

Abstract

Athyrium yokoscense, a type of fern that grows vigorously in mining areas in Japan, is well known as a Cd hyperaccumulator as well as a Cu, Pb and Zn tolerant plant. However, no information is available on As accumulation of A. yokoscense, although it often grows on soils containing high levels of both heavy metals and As. In this study, young ferns collected from a mine area were grown in media containing As-spiked soils or mine soil in a greenhouse for 21 weeks. Athyrium yokosense was highly tolerant to arsenate and survived in soils containing up to 500 mg As (V) kg^?1. The addition of 100 mg As (V) kg^?1 resulted in the highest fern biomass (1.95 g plant^?1) among As-spiked soils. Although the As concentration of the fern was lower than other As hyperaccumulators, such as Pteris vittata, A. yokoscense could hyperaccumulate As in mature and old fronds. Arsenic was accumulated most efficiently in old fronds (922 mg kg^?1) in the media containing 5 mg As (III) kg^?1. Moreover, higher As accumulation was found in the roots of the ferns, with a range from 506 to 2,192 mg kg^?1. In addition, in the mine soil with elevated concentrations of As and heavy metals, A. yokoscense not only hyperaccumulated As (242 mg As kg^?1 in old fronds), but also accumulated Cd, Pb, Cu and Zn at concentrations much higher than those reported for other terrestrial plants. Athyrium yokoscense accumulated Cd mostly in fronds in high concentrations, up to 1095 mg kg^?1, while it accumulated Cu, Zn and Pb mainly in the roots and the concentrations were 375, 2040 and 1165 mg kg^?1, respectively.     

污泥及其复合肥对蔬菜产量及重金属积累的影响

通过盆栽和小区试验初步探讨了污泥复合肥对蔬菜的增产效应及其对蔬菜吸收累积重金属的影响。结果表明 ,污泥复合肥可显著提高蔬菜产量 ,蔬菜可食部分中的Cu、Zn、Cd含量均在国家食品卫生标准范围内 ,但Pb的含量超出了国家食品卫生标准     

Nutrient inputs to soils and their uptake by alfalfa through long-term irrigation with untreated sewage effluent in Mexico

Abstract. The effects of long-term waste water irrigation on soil fertility and nutrient supply to alfalfa ( Medicago sativa ) have been investigated in an area near Mexico City Waste water irrigation has improved the nutrient balance of the soil in respect of total nitrogen and available phosphorus. In contrast Na has displaced Ca and diminished the Ca saturation of the soil. In consequence, Ca in alfalfa tissue has decreased and phosphorus and sodium increased after 80 years of waste water irrigation. Estimates of the N-balance suggest that substantial amounts of N are being lost, probably with consequent eutrophication of the groundwater.     

Effects of heavy metal accumulation in apple orchard soils on microbial biomass and microbial activities

Abstract

The effects of heavy metals (Cu, Pb, and As) accumulated in apple orchard surface soils on the microbial biomass, dehydrogenase activity, and soil respiration were investigated. The largest concentrations of total Cu, Pb, and As found in the soils used were 1,010, 926, and 166 mg kg^?1 soil, respectively. The amounts of microbial biomass C and N, expressed on a soil organic C and soil total N basis, respectively, were each negatively correlated with the amounts of total, 0.1 M HCI-extractable, and 0.1 M CaCl₂-extractable Cu as logarithmic functions, the correlation coefficient being lowest for the 0.1 M CaCl₂extractable Cu. Nevertheless, they were not correlated with the soil pH which was controlling the solubility of Cu in 0.1 M CaCl₂. The dehydrogenase activity expressed per unit of soil organic C was also negatively correlated with the amounts of total, 0.1 M HCI-extractable Cu, and 0.1 M CaCl₂-extractable Cu as logarithmic functions. However, the correlation coefficient was highest for the 0.1 M CaCl₂-extractable Cu. Although the soil respiration per unit of soil total organic C did not show any significant correlations with the total concentrations of heavy metals, it showed negative significant correlations with the amount of 0.1 M HCI-extractable Cu, and to a greater extent, with the amount of 0.1 M CaCl₂-extractable Cu. Both the dehydrogenase activity and respiration per unit of soil total organic C increased significantly with increasing soil pH. These results suggested that in apple orchard soils with heavy metal accumulation the microbial biomass was adversely affected by the slightly soluble Cu, whereas the microbial activities by the readily soluble Cu whose amount depended on the soil pH. The respiration per unit of microbial biomass C showed a positive significant correlation with the logarithmic concentration of total Cu. Furthermore, the contribution of fungi to substrate-induced respiration increased with increasing total Cu content in the soils.     

The movement of metals applied to soils in sewage effluent

Water, Air, & Soil Pollution - Land treatment is increasingly being utilized as a method of waste disposal for both sewage effluent and sludges. While there has been considerable attention...     

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。     

肥料重金属含量状况及施肥对土壤和作物重金属富集的影响

本文对肥料中重金属的含量状况以及施肥对土壤和农作物重金属累积影响的研究进展进行了系统分析和总结。过磷酸钙中锌（Zn）、 铜（Cu）、 镉（Cd）、 铅（Pb）含量高于氮肥、 钾肥和三元复合肥,有机-无机复混肥料中的Pb含量高于其他化肥。有机肥如畜禽粪便、 污泥及其堆肥中的重金属含量高于化肥,猪粪中的Cu、 Zn、 砷（As）、 Cd含量明显高于其他有机废弃物,鸡粪中铬（Cr）含量高;污泥和垃圾堆肥中Pb或汞（Hg）含量高。商品有机肥Zn、 Pb和镍（Ni）含量高于堆肥,Hg含量高于畜禽粪便。多数研究表明,氮磷钾配施与不施肥相比土壤Cd和Pb含量增加,施用有机肥比不施肥提高土壤Cu、 Zn、 Pb、 Cd含量。施用化肥对农作物重金属富集的影响不明确,而施用有机肥可提高作物可食部位Cu、 Zn、 Cd、 Pb 的含量,影响大小与有机肥种类、 用量、 土壤类型和pH以及作物种类等有很大关系。在今后的研究中应着重以下几个方面, 1）典型种植体系下土壤重金属的投入/产出平衡; 2）不同种植体系下长期不同施肥措施对土壤重金属含量、 有效性影响的动态趋势; 3）典型种植体系和施肥措施下土壤对重金属的最高承载年限; 4）现有施肥措施下肥料中重金属的最高限量标准。     

Potential Pb,Cd, Zn and B contamination of sandy soils after different irrigation periods with sewage effluent

Long-term use of sewage water for irrigation enhances the accumulation of trace elements in the soil and may contribute to contamination in low-lying areas. Therefore, this study investigated the extent of pollution introduced by Pb, Cd, Zn and B to the sandy soils of Abu Rawash and El-Gabal El-Asfar areas, Egypt, which have been irrigated with sewage water for up to 67 yr. Results revealed that prolonging the periods of irrigation was associated with significant increases in the total and available forms of Pb, Cd, Zn and B. These elements tended to accumulate in the surface layers, with the exception of B which increased at lower depths. The relative percentage of the available to total element forms reflected the low solubility and availability of both Pb and B compared with Cd and Zn. However, in all cases, the concentrations of these elements have not accumulated to toxic levels after 67 yr of sewage irrigation. Nevertheless, care and good management should be considered in the future with continuous use of sewage water for irrigation.     

冬小麦再生水灌溉时水分与氮素利用效率的研究

农田水氮利用效率的研究可为农田灌溉和施肥提供相应的科学依据。该文用田间实验研究再生水灌溉条件下冬小麦水分与氮素的利用效率。田间试验设置了高、中、低3个不同灌水水平下的清水灌溉加施肥、再生水灌溉加施肥和再生水灌溉不施肥(仅施底肥)9个处理，试验结果表明：灌水量、灌溉水质、施肥量对冬小麦株高的影响很小；叶面积指数随灌水量的减少而减小；再生水灌溉加施肥条件下的产量最高。不同灌溉水量条件下，冬小麦再生水灌溉的耗水规律与清水灌溉的耗水规律十分接近，且累积耗水量随灌溉水量的增大而增加；水分利用效率与灌溉水质和施肥无关，仅与灌水量有关，且随灌溉水量的增加而减少。氮的利用效率受灌水量、灌溉水质、施肥量的影响较小。     

Compost use in viticulture: Effect on heavy metal levels in soil and plants

Abstract

The purpose of this study was to examine the long‐term effect of compost application on the heavy metal content in soil, leaves, and fruit of grape (Vitis vinifera). Two types of compost were tested in a vineyard. One was compost with a low heavy metal content, which was derived from sewage sludge and bark (SB compost). The other type was compost with a higher concentration of metals, which was derived from municipal solid waste (MSW compost). For 6 years, the levels of zinc (Zn), copper (Cu), nickel (Ni), lead (Pb), cadmium (Cd), and chromium (Cr) in their total (aqua regia digestion), EDTA‐extractable, and DTPA‐extractable forms were monitored in soil, leaves, musts, and wines. The resulting data clearly demonstrate that SB compost did not cause any significant increase in heavy metal levels in the soil and the plants. Thus, this type of compost can be used for soil fertilization with no danger either to the environment or to crops. In contrast, the use of MSW compost caused a significant accumulation of Ni, Pb, Cd, and Cr in the soil, in vegetation, and in musts. Skin‐contact fermentation dramatically decreased the heavy metal content of the wines. The concentration of heavy metals in plant tissues was found to be positively correlated with the DTPA‐extractable form of the metals in the soil, but not correlated with the total or the EDTA‐extractable forms.