重金属污染土壤清洗导致几种营养元素流失的研究

通过HCl、柠檬酸、EDTA这3种提取剂对Pb、Cd、Cu、Zn污染土壤的漫提试验，研究了土壤清洗洗脱重金属的效果，并探讨了土壤清洗导致K、Ca、Mg、Fe、Mn这几种营养元素的流失和有效性的改变。试验结果表明，土壤清洗能有效地洗脱土壤中的Ph、Cd、Cu、Zn，伺时也造成了土壤中K、Ca、Mg、Fe、Mn的流失，降低了其中部分营养元素的有效性。EDTA对重金属的洗脱能力大于HCl和柠檬酸。HCl漫提造成的K、Ca、Mg的流失量大于柠檬酸和EDTA，柠檬酸浸提造成的Fe流失量大于HCl和EDTA，EDTA漫提造成的Mn流失量大于HCl和柠檬酸。HCl和柠檬酸浸提降低了土壤K、Ca、Mg的有效性EDTA浸提提高了土壤K的有效性。降低了土壤Ca的有效性。在高浓度时（50mmol／L），EDTA显著地降低了土壤Mg的有效性。HCl漫提导致土壤K的有效性下降比柠檬酸严重，高浓度的EDTA浸提导致土壤Ca的有效性下降比HCl和柠檬酸严重。HCl、柠檬酸、EDTA浸提都能提高土壤中Fe的有效性．且EDTA的效应大于其它2种萃取剂；在低浓度时，3种提取剂都能提高土壤中Mn的有效性，且以柠檬酸的作用最为明显，当提取剂浓度增加时，Mn的有效性有所回落。     

广东省沿海城市居民膳食结构及食物污染状况的调研——对持久性卤代烃和重金属的人体暴露水平评价

自改革开放以来,广东沿海城市逐步成为经济发展的热点地区。飞速的经济发展、快速的城市化进程以及有机氯农药的历史使用等原因,使得广东省内环境介质受到持久性卤代烃和重金属污染,这些污染物最终主要通过食物影响到处于生物链终端的人类。本文运用随机抽样的方法对广东省经济较发达的12个沿海城市居民的膳食情况进行问卷调查,分析其膳食营养状况。同时,结合该地区食物中持久性卤代烃和重金属的污染水平,对居民通过食物摄人的污染物进行人体暴露水平评价。结果表明,广东省沿海城市居民对蛋类、豆制品、乳品及水果的消费量均高于广东省平均水平,而蔬菜、禽肉和谷物的摄入量却低于广东省平均水平。与国家推荐摄人量相比,居民对蔬菜的摄入量仅为推荐量的一半,乳品的摄入也明显偏低。若以每标准人为单位,广东省沿海居民日均摄入能量低于全国平均值,占参考摄入量的90％,视黄醇、硫胺素、核黄素的日均摄入量也低于我国推荐值,而蛋白质和脂肪的日均摄入量则明显超出推荐值。而且,广东省沿海城市居民每日通过食物对持久性卤代烃的摄人量没有超过世界粮农组织和世界卫生组织（FAO／WHO）规定的每日允许摄入量。讨论了膳食中铅、砷、镉、铬4种金属的人体暴露情况,金属铅、砷和铬的暴露水平处于安全线内,但是金属镉的日均摄入量与FAO／WHO规定的最大耐受量相同。     

The Global Exposure of Forests to Air Pollutants

The tall, aerodynamically rough surfaces of forests provide for the efficient exchange of heat and momentum between terrestrial surfaces and the atmosphere. The same properties of forests also provide for large potential rates of deposition of pollutant gases, aerosols and cloud droplets. For some reactive pollutant gases, including SO₂, HNO₃ and NH₃, rates of deposition may be large and substantially larger than onto shorter vegetation and is the cause of the so called "filtering effect" of forest canopies. Pollutant inputs to moorland and forest have been compared using measured ambient concentrations from an unpolluted site in southern Scotland and a more polluted site in south eastern Germany. The inputs of S and N to forest at the Scottish site exceed moorland by 16% and 31% respectively with inputs of 7.3 kg S ha^-1 y and 10.6 kg N ha^-1 y^-1. At the continental site inputs to the forest were 43% and 48% larger than over moorland for S and N deposition with totals of 53.6 kg S ha^-1 y^-1 and 69.5 kg N ha^-1 y^-1 respectively. The inputs of acidity to global forests show that in 1985 most of the areas receiving > 1 kg H⁺ ha^-1 y^-1 as S are in the temperate latitudes, with 8% of total global forest exceeding this threshold. By 2050, 17% of global forest will be receiving > 1 kg H^-1 ha^-1 as S and most of the increase is in tropical and sub-tropical countries. Forests throughout the world are also exposed to elevated concentrations of ozone. Taking 60 ppb O₃ as a concentration likely to be phytotoxic to sensitive forest species, a global model has been used to simulate the global exposure of forests to potentially phytotoxic O₃ concentrations for the years 1860, 1950, 1970, 1990 and 2100. The model shows no exposure to concentrations in excess of 60 ppb in 1860, and of the 6% of global forest exposed to concentrations > 60 ppb in 1950, 75% were in temperate latitudes and 25% in the tropics. By 1990 24% of global forest is exposed to O₃ concentrates > 60 ppb, and this increases to almost 50% of global forest by 2100. While the uncertainty in the future pollution climate of global forest is considerable, the likely impact of O₃ and acid deposition is even more difficult to assess because of interactions between these pollutants and substantial changes in ambient CO₂ concentration, N deposition and climate over the same period, but the effects are unlikely to be beneficial overall.     

我国污灌污水中重金属含量特征及年代变化规律

通过查阅文献数据库,统计发表的我国各地污灌污水中的重金属含量,并对数据进行统计分析,总结近30a来我国污灌污水中重金属的含量特征及年代变化规律。文献数据统计结果表明,近30a来我国污灌污水中重金属Pb、Cr、Zn、Ni的含量均值或中位值随年代逐步降低,Hg、As平均含量呈先上升后下降的趋势,Cu、Cd平均含量则是呈现先下降后上升的趋势;近30a来污灌污水中8种重金属浓度的平均值或中位值均低于农田灌溉水质标准（GB5084—2005）,但污灌污水中重金属浓度的90%分位值均超过该农田灌溉水质标准,污灌污水中重金属浓度75%分位值20世纪80年代Hg、Pb、Cd超标,90年代Hg、Cr、As超标,近10aCd、As超标。对污灌污水中Hg、Cd、As在污染源头控制中需要优先控制。     

Decreases in Condition and Fecundity of Freshwater Fishes in a Highly Polluted Reservoir

Despite many efforts for pollution abatement in aquatic ecosystems, there are still some cases of high accumulation of industrial pollutants due to past activities. In Flix reservoir (Ebro River, Spain), there are around 200,000–360,000 tons of industrial pollutants with a high concentration of heavy metals and organochlorides due to the activity of an organochlorine industry during more than half a century. This exceptional amount of pollutants provides a good opportunity (and need) to analyse their effects on fish populations under natural conditions, which is rarely available to ecotoxicologists. We compared the reproductive traits and prevalence of diseases and parasites at this impacted area with a neighbouring upstream reservoir unaffected by the pollution (reference sites) and also to downstream sites. Deformity, eroded fin, lesion and tumour (DELT) anomalies and ectoparasites were clearly more frequent at the impacted area for several fish species (common carp, roach and pumpkinseed). A significant negative impact of Flix reservoir on condition (eviscerated and liver weights, adjusted for fish size with analysis of covariance) and reproductive traits (gonadal weight and number of mature eggs, adjusted for fish size) was also detected for several fish species. The responses to the pollutants were species-specific, and common carp (Cyprinus carpio) was the species with the clearest effects on fitness-related traits at the impacted area, despite also being among the most tolerant to pollution.     

Responses of Photosynthetic Efficiency,Cell Shape and Motility in Euglena gracilis (Euglenophyceae) to Short-Term Exposure to Heavy Metals and Pentachlorophenol

Euglena gracilis was exposed for 24 hr to concentrationsof copper, nickel, lead and zinc ranging from 0.1 to 2.0 mg L^-1 and to pentachlorophenol ranging from 0.1 to 10.0 mg L^-1. Photosynthetic efficiency (PE) was inhibited by increasing concentrations of the heavy metals. Nickel was foundto be the least toxic of the metals to E. gracilis, whilethe other three metals exhibited similar levels of toxicity. Treatment with pentachlorophenol caused unusual responses of the photosynthetic apparatus probably due to the especially high toxicity of this substance. Both cell shape and motility turned out to be insensitive physiological parameters for the toxicity testing of the substances studied.     

生物质炭修复重金属及有机物污染土壤的研究进展

生物质炭是生物质原料在完全或部分缺氧条件下高温热解后的固体产物,它具有丰富的孔隙结构和较高的碳含量。该物质具有巨大的表面积和较强的阳离子交换能力等特殊性质,对受污染土壤中的重金属和有机物都具有很强的吸附能力,有效地降低这些污染物的生物有效性和在环境中的迁移,对改善土壤环境具有重大意义。近年来我国土壤污染严重,利用生物质炭修复受污染土壤的技术得到了广泛的关注。本文简述了生物质炭修复土壤污染的基本原理,探讨了与其他修复方法相比存在的优势,阐述了国内外近年来利用生物质炭修复污染土壤的研究进展,最后展望了今后需要进一步研究的领域。     

淡水鱼产气荚膜梭菌的分离及毒素型的鉴定

为研究产气荚膜梭菌在淡水鱼中的分布及毒素型,随机采取同一水库的鲤鱼、鲢鱼、鲫鱼、鲶鱼、黄鳝等淡水鱼样品420尾,细菌学方法分离肠内容物中的产气荚膜梭菌,PCR方法检测分离菌株的毒素基因确定毒素型,PCR扩增片段克隆后进行核苷酸序列分析并且与Genebank相应基因进行同源性比较。结果：自75份肠内容物样品中分离出产气荚膜梭菌;58株为C型（α、β毒素基因）,13株为A型（α毒素基因）,4株为B型（α、β、ε毒素基因）;三型菌株均能扩增出特异性2条带;检出基因与Genebank相应基因的同源性为98.15－99.29%。在淡水鱼检出产气荚膜梭菌的α、β、ε、β2毒素基因,在B型产气荚膜梭菌中扩增出2毒素基因均属首次,本研究对水体环境的污染及人类的食品安全有一定的指导意义。     

污泥混配土淋溶液中pH、氮磷及重金属含量的动态变化

以北京市大兴区庞各庄镇污水处理厂的堆肥污泥、生污泥和通州区的熟土为对象,探讨污泥混配土淋溶液中相关指标的动态变化.结果表明,生污泥、堆肥污泥和熟土混配后可降低土壤pH值,增加土壤全氮、全磷含量,同时也增加了土壤中重金属As、Cd、Ni、Cu、Ph的含量,生污泥系列淋滤液中Pb对地下水造成污染的可能性最大;堆肥污泥系列淋滤液中给地下水带来污染可能性最大的因子是As.但各处理中重金属的污染程度都很低,基本符合国家第II类地下水水质标准,因此淋滤液中的重金属基本不会对地下水造成污染.     

Effect of Fluctuating Hydrological Conditions on the Mobility of Heavy Metals in Soils of a Freshwater Estuary in the Netherlands

The objective of this study was to measure the mobility of heavy metals in freshwater estuary soils that are seasonally inundated and to characterize the distribution of sulfide precipitates in these soils. Precipitation and dissolution of labile sulfides may account for changing pore water concentrations of heavy metals in freshwater wetland soils that are subject to temporary flooding or fluctuating groundwater levels. The presence of authigenic zinc- and iron-(mono)sulfide in this type of soils during periods with a high groundwater level was demonstrated by electron microprobe analyses. Because sulfide precipitates are strongly associated with root remnants, fresh soil organic material may be an important intermediary in the sulfur cycling and, consequently, in the behavior of heavy metals in these freshwater soils. Oxidation of labile sulfides may be partly responsible for the increased zinc and sulfate concentrations in the pore water during periods with low groundwater levels. Heavy metals may also be mobilized by degradation of their host phase organic matter during periods with high biodegradation.     

重金属与农药复合污染研究现状及展望

农业生态环境与人类生存质量息息相关,而随着工农业的发展,进入环境中的污染物种类和数量明显增加,环境污染已不再是单一污染的理想状态。在农业生态系统中,重金属和农药复合污染较为突出,尽管总体研究还较薄弱,但也逐步成为近年来农业环境科学研究的热点。本文就重金属和农药复合污染在土壤-植物系统中环境行为、交互作用及机制等方面的研究进展和动态进行综合分析,并对一些研究热点和需要强化的方向进行展望。     

Hyperaccumulative Characteristics of Weed Species to Heavy Metals

Phytoremediation, which mainly employs hyperaccumulators to remove heavy metals from contaminated soils, is receiving more attention world-wide. The identification of hyperaccumulators is still a key step for phytoremediation. This research is devoted to identify some plants with hyperaccumulative characteristics from weed species. In a pot culture experiment, the hyperaccumulative characteristics of 13 weed species in 11 families to Cd, Pb, Cu and Zn were examined. The result showed that Taraxacum mongolicum and Rorippa globosa indicated some Cd hyperaccumulative properties. In a sample-analysis experiment conducted in a Pb?Zn mining area, T. mongolicum and R. globosa also displayed the same hyperaccumulative characteristics. However, in a concentration gradient experiment, Cd content in shoot of T. mongolicum was not higher than 100 mg/kg (DW, dry weight), the minimum Cd concentration for a Cd-hyperaccumulator in any treatment. The concentration of Cd in the stems and leaves of R. globosa were greater than 100 mg/kg, under the conditions of the soils spiked with 25 and 50 mg/kg Cd. The Cd accumulation factors and translocation factors in the shoots of R. globosa were higher than 1 too, and the plant biomasses did not decrease significantly (p?<?0.05) compared with the control. Thus, we conclude that only R. globosa showed the whole Cd-hyperaccumulator properties, which is a Cd-hyperaccumulator.     

不同土地利用方式下土壤重金属分布规律及其生物活性变化

为了解不同土地利用方式下土壤环境的质量状况,以崇明岛农田、生活区、工业区、湿地、公路旁和港口码头等6种土地利用方式的土壤为研究对象.研究了土壤重金属Cu,Cr,Pb的分布规律和土壤生物活性的变化.结果表明:与国家土壤环境质量一级标准相比,工业区土壤重金属Cu,Cr,Pb全量均值超标率最高,分别为109.43%,7.08%,147.54%,而湿地超标率最低.不同土地利用方式下土壤酸性磷酸酶和脲酶活性差异较大,但脱氢酶活性变化不明显;微生物中细菌占绝对优势,细菌和放线菌数量变化较小,而真菌数量变化较大;土壤微生物总数从大到小的顺序为:湿地>港口>公路旁>工业区>农田>生活区;而土壤呼吸强度没有显著性变化.     

酸雨地区蔬菜对重金属的吸收及重金属健康风险基准的估算

通过盆栽实验,以小白菜(上海青)、大白菜和萝卜为指示作物,研究了酸雨作用下Cu,Zn,Pb,Cd,Cr和Ni复合污染物在土壤-作物系统中的吸收与富集情况。结果表明,酸雨-重金属复合污染处理使Cu,Pb,Cr和Ni在蔬菜中积累量明显高于对照处理;Zn和Cd一般只有在复合污染处理中外源Zn或Cd含量较高时才明显高于对照处理。与对照相比,酸雨-重金属复合污染处理使Pb和Ni的富集系数增大,Cu的富集系数多数情况下增大,Cd的富集系数多数情况下减小,Zn和Cr富集系数的变化在不同蔬菜之间存在较明显的差异;重金属在不同蔬菜中的富集系数一般表现为萝卜>上海青>大白菜,蔬菜中不同重金属富集系数一般表现为Zn>Cd>Ni>Cu>Pb>Cr。酸雨-重金属复合污染条件下蔬菜中重金属积累量与其在土壤中总量之间的相关性均达到显著或极显著水平。以大宗蔬菜上海青、大白菜和萝卜为指示作物对酸雨地区蔬菜地中重金属的健康风险基准进行了估算,这对开展酸雨地区土壤重金属环境容量评价、重金属污染修复目标及地方性土壤环境质量标准的制订提供了参考依据。     

近20年山东省典型农田土壤中重金属含量变化特征及积累速率估计

以山东省基本农田为研究对象,于2009年采集60个0 ～ 20 cm耕层土壤样本,分析了土壤中Cu、Zn、Pb、Cd有效态含量和全量,并与1989年调查资料比较,研究近20年山东省土壤重金属全量和有效态含量变化特征.结果表明:山东省农田土壤Zn、Cu、Pb全量均有样点超过国家土壤环境质量二级标准(GB15618-1995),其中有28.78％的样点Cu超标,5.26％的样点Zn超标,8.00％的样点Pb超标,所有调查样点均未发现Cd超标.近20年,山东省农田土壤中Pb全量变化幅度最大,与1989年相比,褐土区增加了5.81倍;Cd全量在棕壤中变化幅度最小,仅增加了1.33倍.Zn、Cu、Pb、Cd全量在3种土壤中变化幅度为:褐土＞潮土＞棕壤.与1989年相比,山东省农田土壤有效态Cu含量增加1.22 ～ 1.70倍,Zn增加了11.50 ～ 16.60倍.山东省土壤重金属积累速率,褐土≈潮土＞棕壤.Cu、Zn、Pb的积累速率和年变化速率明显高于20世纪七八十年代太湖地区水稻土,Cd的积累速率和年变化率远远低于太湖地区水稻土.     

European Population Exposure to Airborne Pollutants Based on a Multivariate Spatio-Temporal Model

In this paper, we estimate the distribution of population by exposure to multiple airborne pollutants, taking into account the spatio-temporal variability of daily air quality and the high-resolution spatial spread of human population around Europe. In particular, we consider monitoring network data for five pollutants, namely carbon monoxide, nitrogen dioxide, ozone, coarse and fine particulate matters. The spatial information contained in the large dataset of daily continental air quality is exploited using a multivariate spatio-temporal model capable to cover cross correlation among pollutants, covariates, and missing data as well as spatial and temporal variability and correlation. At the same time, the model is simple enough to be feasible for the large dataset of daily continental air quality over three years. Maximum likelihood estimation is performed using the EM algorithm, and kriging-like spatial estimates are used to compute high-resolution exposure distribution. Moreover, a novel semi-parametric bootstrap technique is used to assess the exposure distribution uncertainty. In this way, we compare the daily population exposure of 33 European countries and three important metropolitan areas in years 2009–2011 using a single flexible model. Extensive tabulations and graphs are reported in the supplementary material.     

重庆市蔬菜区重金属污染现状

本文通过对不同区域菜地大气污染物和灌溉水、土壤、蔬菜重金属平均含量比较发现,污染区大气污染物均大于清洁区;灌溉水和土壤重金属在不同区域差异不大;不同蔬菜品种重金属在不同区域表现不一致,叶菜类基本表现为污染区大于清洁区,说明叶菜类蔬菜重金属污染主要由大气污染引起。苋菜、莴笋重金属含量较高,说明富集重金属能力较强。蔬菜重金属含量同食品卫生限量标准比较表明超标蔬菜品种为苋菜、莴笋、葱子,超标重金属为Pb、Cd、Cr。同一蔬菜品种莴笋重金属Pb、Cd、Hg、As平均含量在污染点的下风向高于上风向,说明Pb、Cd、Hg、As与大气污染有直接关系。蔬菜重金属相关性分析表明Cr、Hg具有明显的协同和拮抗作用。     

Environmental Evaluation of Metals in Sediments and Dragonflies Due to Sugar Cane Cultivation in Neotropical Streams

The use of fertilizers, containing different metals ions such as lead(II), chromium(III), cadmium(II), copper(II) and zinc(II), in the soil, for sugar cane cultivation, may cause impacts on the hydric resources of the adjacent areas. The scope of this study was to evaluate the impacts of sugar cane cultivation based on metal concentrations in sediments and dragonflies (Odonata). The bioavailability of such metals was determined in ten Neotropical streams. Six streams were located on areas with sugar cane cultivation, without riparian vegetation (classified as impacted area) and four streams were located on forested areas (reference sites). The results showed that there are high concentrations of metals in the sediments and dragonflies in streams located on impacted areas. The contamination by metals of aquatic insects of terrestrial adult life cycle, as Odonata organisms, represents a dangerous link for the transference of metals to upper trophic levels, as fishes, reptiles, birds and mammals.     

支流泥石流入汇对主河河型成因的影响

探讨了泥石流入汇后随主河水流运动的几种可能形态和运动特点,分析了泥石流入汇与主河河床演变的关系.根据所提出的河型分类模式,分析了泥石流对河型形成的影响,按河岸可动性与河床可动性的比值,将主河河床演变分为单股和多股;按主河水沙搭配指数的大小将主河分成低滩和高滩.对不同类型河流河床演变进行了分析,为进行泥石流入汇对主河水沙运动与河床演变的影响的研究奠定了基础.     

污泥施田后土壤和玉米植株中重金属分布特征

对施污泥剂量分别为10、30和60thm-2的土壤,采用修正的BCR三步连续提取法分步提取并分析Pb、Cd、Cu、Zn的不同形态。利用高压密封消解技术和电感耦合等离子体质谱(ICP-MS)分析Pb、Cd、Cu、Zn在玉米器官中的分布及其转移富集特征。施污泥土壤中重金属主要以残渣态存在。施污泥量为常规用量的6倍时,即相当于连续6年施污泥的土壤中重金属Pb、Cd、Cu、Zn的含量基本未超过我国土壤环境质量标准。4种重金属在弱酸性土壤中残渣态含量比例的高低依次为CuZnCdPb。施污泥土壤上Pb、Cd在玉米各器官中的平均含量顺序为:茎叶根籽粒;Cu为:根茎叶籽粒;Zn为:根籽粒茎叶。玉米对于各元素的EC值按高低顺序依次为CuZnCdPb。