广东某硫酸废渣堆渣场周围土壤铊污染的地累积指数评价

对广东某含铊黄铁矿冶炼废渣堆渣场周围土壤铊污染状况进行了研究与评价。结果表明,废渣周围土壤已受到了明显的铊污染,污染物主要集中在土壤0~16.5 cm范围,并且表现出沿垂直方向向下迅速降低的特点;土壤表层的铊吸附量未达到饱和状态,铊污染物将继续在土壤表层发生累积作用。地累积指数法评价的结果是:废渣下伏土壤0~6 cm范围铊达到中度污染水平,而在土壤约14.5 cm以下没有受到铊的污染;相对于下伏土壤,废渣外围土壤污染更为严重,其中土壤0~1cm铊已经达到中~强度污染,土壤1~5 cm范围铊为中度污染,而在土壤约14.5 cm以下没有受到铊的污染。地质累积指数法应用于土壤铊污染评价是可行的,但是不能表明铊在土壤中存在状态、迁移能力以及生物有效性。     

广东某硫酸厂含铊冶炼废渣堆放场土壤铊剖面特征及迁移行为

重点研究了广东某硫酸工业废渣堆放场周围土壤剖面中铊的污染特征及迁移影响因素。研究表明,铊污染物主要集中在土壤0~16.5cm范围,并且表现出沿垂直方向向下迅速降低的特点。土壤中铊污染物活动态的比例很高,主要以铊的铁锰氧化物结合态(TlFe/MnOx)存在,铊的可交换态(Tlexc)、铊的碳酸盐结合态(Tlcar)、TlFe/MnOx在土壤中迁移性强,而铊的有机结合态(Tlorg)和铊的残余态(Tlres)迁移性相对较弱。土壤pH值是影响铊污染物在土壤中迁移的主要因素,铁锰氧化物/氢氧化物、有机质、土壤粒度组成、CEC(阳离子交换容量)是影响铊迁移的次要因素。     

生态指数法在土壤评价中的应用

作者建议以温度、水分、大陆性系数(KK值)、地形以及土壤的一系列属性作为评价土壤肥力及生产力的依据。并将此法应用于淮阴市的土壤评价上,取得了较满意的结果。     

模糊数学和污染指数法在土壤重金属污染中的应用

依据土壤质量评价中所存在的模糊性和渐变性的特点,采用模糊数学和污染指数法对长春市土壤中重金属(Pb、Cu、Ni,Zn)综合污染状况进行环境质量评价,并进一步对各评价因子在不同功能区的污染程度和来源进行分析.结果表明,长春市土壤环境质量基本上为二级水平,已超过中国土壤自然背景值.各功能区土壤环境优劣顺序为工业区＞住宅区＞郊区耕地＞公园＞开发区;不同功能区各评价因子在土壤中污染水平差异较大,主导污染因子为Ni,已经达到中度污染水平,除此之外,Pb污染较重.     

基于地积累指数法和潜在生态风险指数法评价广西某蔗田土壤重金属污染

采用地积累指数法和潜在生态风险指数法对广西某蔗田土壤中重金属污染进行评价。结果表明:4种重金属元素的地积累指数污染程度由强到弱依次为:CdZnPbCu,潜在生态危害指数污染程度由强到弱依次为:CdPbCuZn,其中Zn的影响程度发生了变化。2种评价方法的结果存在差异,蔗田土壤的地积累指数污染程度处于无污染情况,而潜在生态危害指数污染程度处于低度危害程度。潜在生态危害指数考虑外源重金属的富集程度和不同重金属的生物毒性的影响,使其评价结果更准确。     

综合指数质量评价模型在太原市土壤重金属污染评价中的应用

采用3种综合指数质量评价模型,以太原盆地土壤重金属元素背景值为评价标准,计算了太原市表层土壤重金属的综合污染指数.对比分析3种评价模型以后,认为用加权叠加综合指数评价模型能客观地反映太原市土壤重金属真实的污染状况.在此基础上,对太原市重金属进行了环境质量分区,并统计出不同环境质量区占总调查面积的百分比.     

Hakanson指数法在评价土壤重金属生态风险上的应用进展

Hakanson指数法是目前重金属元素潜在生态风险评价的常用方法。该方法开始被应用于研究河流沉积物重金属污染评价中,后逐步被引进到土壤重金属污染的研究,并被广泛使用。分析发现,Hakanson指数法对于评价土壤重金属生态风险是有效的,但也存在不足之处。本文综述了众多专家学者在利用Hakanson指数法进行土壤重金属生态风险评价中的研究成果,介绍了利用土壤重金属元素形态、修改毒性响应系数和生态危害风险指数等对Hakanson指数模型进行改进的方法和步骤,讨论了Hakanson指数法在评价土壤重金属生态风险方面的应用进展。     

有机质在土壤重金属污染治理中的应用

根据对土壤重金属污染的严重性和目前国内外对此治理方法的分析，提出有必要在较大污染面积的土壤上实行有机质改良；还阐述了有机质对重金属污染净化作用的主要机制及调控措施。有机质改良法兼顾了经济效益、环境效益及社会效益三者的统一，是土壤重金属污染治理的一个最佳方向之一。     

基于内梅罗指数法的复垦村庄土壤重金属污染评价及空间分布

以复垦村庄——山西省泽州县西郜压煤搬迁村庄为研究区,采集和测定了村庄内18个样点中Hg,As,Pb,Cd,Cr的重金属含量,并通过内梅罗指数法对重金属污染程度进行评价和空间分析。研究表明:西郜村中土壤的重金属综合污染程度达到了中度污染程度,其中Hg元素污染程度最高;0—20cm土壤中重金属污染程度要高于20—40cm土壤;研究区耕地处重金属污染程度较轻,而土路处由于交通运输及人类活动从而导致重金属污染程度较高,对于宅基地区域,重金属污染程度较高区域都分布在修建年代不久的宅基地所在位置,研究结果可为开展村庄复垦重金属治理提供一定借鉴。     

基于三次样条插值法的土壤中有机氯污染研究

根据2003年、2007年以及2009年的北京官厅水库地区表层土壤中有机氯农药(OCPs)残留实验数据,应用三次样条插值法对缺失年份的数据进行了补充,并预测了2010年的数据。在此基础上,分析了各采样点OCPs浓度时间变化规律及原因,探讨了影响有机氯农药降解的因素,并且参照国家土壤环境质量评价标准,对区域表层土壤中有机氯的污染现状进行了评价。结果显示:部分样点OCPs含量随着时间的变化存在反弹,判断存在OCPs的外源性输入;土壤质地对OCPs降解速率有很大程度上的影响,立地植被的影响不显著;对比国家土壤质量一级标准来看,2003年至2009年均未检出总六六六(∑HCH)超标样点,采样点的总滴滴涕(∑DDT)浓度至2009年也均下降至国家土壤环境质量标准一级限值内;预计到2010年,采样点总六六六浓度基本保持恒定,总滴滴涕仍维持良好的降解趋势。     

Dissolution of slag fertilizers in a paddy soil and Si uptake by rice plant

Abstract

Maize (Zea mays L.) cv. Ganga 2 was grown in refined sand at three levels of copper: deficient (0.00065 mg L^-1), adequate (0.065 mg L^-1), and excess (6.5 mg L^-1), each at three levels, deficient (0.00065 mg L^-1), adequate (0.065 mg L^-1), and excess (6.5 mg L^-1) of zinc. Excess Cu magnified the zinc deficiency effects in maize by lowering further the biomass, the concentration of leaf Zn, activities of carbonic anhydrase, aldolase, and ribonuclease and intensified the visible foliar symptoms of Zn deficiency. The effects of Cu deficiency, low dry weight, the concentration of leaf Cu and activities of cytochrome oxidase and polyphenol oxidase were enhanced by excess Zn. Synergism was observed between combined deficiency of Cu and Zn and Cu or Zn deficiency, because the depression in the parameters characteristic of Cu or Zn deficiency was more pronounced when both Cu and Zn were deficient than when Cu or Zn was deficient. Antagonism was observed in some parameters between combined excess of Cu and Zn and Cu or Zn excess. Dry weight was decreased further when both Cu and Zn were in excess than when either Cu or Zn was in excess. After the infiltration of Cu and Zn together to the leaf discs from deficient Cu-deficient Zn treatment, the increase in the concentration of leaf Zn and the activities of aldolase, carbonic anhydrase, polyphenol oxidase, and cytochrome oxidase was more pronounced than after the infiltration of Cu or Zn singly. Discontinuance of excess Zn supply from the excess Zn-deficient Cu treatment increased the concentration of leaf Cu and activities of polyphenol oxidase and cytochrome oxidase and lowered the concentration of Zn. Similarly the discontinuance of excess Cu supply from the leaf discs in the “excess Cu-deficient Zn” treatment increased the leaf Zn concentration and the activities of carbonic anhydrase and aldolase.     

Proposed assessment of the vulnerability of European soils to pollution using a soter shell approach

After recent unanticipated occurrences of environmental pollution caused by the time-delayed and sudden release of contaminants previously believed to be held firmly in soils, awareness has increased that the vulnerability of soils to chemical degradation needs to be assessed and mapped. Although some soils appear to be capable of receiving and holding chemical compounds while at the same time retaining their ecological functions, others are readily damaged. Procedures for identifying areas where vulnerable soils occur are presented, with special reference to the minimum soil data sets that would be required in a small scale study at the European level using geographical information systems. These data can readily be compiled, stored and processed with the relational database management system developed for SOTER, The 1:1 million world soil and terrain digital database project of the International Society of Soil Science, which is co-ordinated by the International Soil Reference and Information Centre. the proposed initial soil vulnerability programme would essentially serve to increase awareness about areas prone to chemical soil degradation, and will form the basis for implementing soil pollution assessment programmes at larger scales (1:1 M to 1:250 000). the latter national or regional programmes would include the identification of the major sources of soil pollution, and measurement of the accumulated load and the rate of loading according to uniform and standardized procedures, providing the conceptual basis for developing process based models to assess where particular types of soil degradation are likely to occur.     

Availability and plant uptake of nutrients following the application of paper pulp and lime to tropical acid soils

Availability and plant uptake of nutrients were evaluated in three tropical acid soils (Kandiudult) amended with paper pulp and lime under greenhouse conditions. Amendments were applied to attain target pH values of 5.5, 6.0, and 6.5. A control treatment (no paper pulp or lime added) was also included. Rye grass (Lolium perenne L.) as a test plant was grown for three successive cycles of 40 days each. Extractable nutrients and cumulative nutrient uptake were determined. The application of paper pulp or lime resulted in a significant increase in exchangeable Ca and K and a decrease in exchangeable Mg and extractable Fe, Mn, and Zn. Amendment of soils with paper pulp or lime increased plant uptake of Ca and Mg and decreased that of K, Mn, and Zn. Both amendments behaved similarly, but the effect of lime seemed generally greater than that of paper pulp. Paper pulp in tropical acid soils behaved as a liming agent rather than an organic amendment. Similar to lime, amendment of soils with paper pulp resulted in an increase in availability of Ca and Mg and in a decrease in availability of K, Mn, and Zn for plants. Soil extractions appeared to be appropriate for assessing the availability of Ca, Mn, and Zn. Soil pH and effective cation exchange capacity positively influenced the availability of Ca and negatively the availability of Mn and Zn. Thus, the precision of predicting nutrient availability in paper pulp amended tropical acid soils could be improved by including soil pH or effective cation exchange capacity in relevant regression equations.