二球悬铃木不同器官对空气中Cu、Ni、Pb和Zn的累积作用

以交通繁忙区(污染点)和相对清洁区(对照点)道路两侧的二球悬铃木〔Platanus acerifolia ( Ait.) Willd.〕为研究对象,测定了不同器官(包括主干、老树皮、2年生枝条、1年生枝条、腋芽、叶片和果实)中Cu、Ni、Pb和Zn的含量,并对污染点二球悬铃木各器官中4种重金属元素的累积量和污染指数及二者的分布比例进行分析。结果表明：二球悬铃木体内重金属元素的含量因样点、器官及元素的不同而呈现不同的变化规律,污染点4种重金属元素的累积量及其分布比例、污染指数及其分布比例则因器官和元素的不同而有明显差异。总体上看,污染点各器官的Cu、Ni、Pb和Zn的含量均高于对照点且差异显著(P<0.05);4种重金属元素相比较,均以Zn含量最高,Cu含量次之,而Ni和Pb含量则较低;在不同器官中同一重金属元素的含量也有明显差异,其中,Cu、Ni和Zn含量均在腋芽中最高,Pb含量在2年生枝条中最高。4种重金属元素的累积量及其分布比例均在叶片中最高,在老树皮中次之,在1年生枝条、2年生枝条和腋芽中均较低;而4种重金属元素的污染指数及其分布比例则在老树皮中最高,在叶片中次之。研究结果显示：二球悬铃木各器官对空气中的重金属元素均有一定的吸滞能力,并且叶片和老树皮的吸滞能力明显优于其他器官。     

Pb 在水花生愈伤组织中的超微定位及对矿质元素的影响

水体重金属污染已经成为一个日益严重的环境问题, 了解水体重金属污染原理、处理水体重金属, 已经成为一个必需解决的课题。由于重金属元素具有难降解、易积累、毒性大等特点, 另外还能被水生植物富集吸收进入食物链危害人畜健康。因此, 植物对重金属毒害的抗性机理以及提高植物抗重金属胁迫能力的探索研究越来越引起人们的关注。虽然在铅(Pb2+)胁迫下植物的抗氧化反应已经有了一些报道, 但有关于植物愈伤组织受到重金属胁迫后变化的研究报道较少。鉴于此, 研究将分布广泛的挺水植物水花生进行愈伤组织培养, 克服了光照、温度、水分及植物生长发育在自然状态下的不可控制性, 使实验数据更具重复性和科学性。经过70%酒精30s、5%次氯酸钠10min 和0.1%升汞10min 消毒后, 在激素为6-BA(3.0 mg/L)和NAA(0.2mg/L)的1/2MS 培养基中培养出水花生茎段的愈伤组织并以此作为研究对象, 以常见的污染环境的重金属离子—Pb2+为胁迫因子。研究了在不同Pb 处理浓度(0、0.2、0.4、0.8 和1.6 mmol/L)下愈伤组织对Pb 的积累、亚细胞分布、亚显微定位及矿质元素的影响。结果表明, 随着培养液中Pb 浓度的增加, (1)愈伤组织体内的Pb 含量极显著上升, 富集系数为2341—2681; (2)各亚细胞组分中的Pb 含量都呈逐渐上升的趋势, 但分配比例明显不均, 分布规律为细胞壁>细胞器>可溶性部分, Pb 胁迫与处理浓度间存在显著的剂量—效应关系, Pb在亚细胞分布与对细胞超微结构的损伤关系密切; (3)超微定位观察发现在细胞壁上分布有大量的Pb 颗粒,细胞内膜结构及基质中也都存在Pb; ⑷Pb 对各亚细胞组分中矿质元素的影响不同, 其中抑制了大量元素P、K、Mg 和微量元素Na、Zn、Mn 的吸收; Ca 在细胞壁中先升后降, 细胞器中逐渐减少, 可溶性部分中则是逐渐增加; Fe 和B 在各亚细胞组分中均表现出先升后降; Cu 在前两个组分中总体呈上升趋势, 可溶性部分中则是先升后降; Si 在细胞壁中逐渐减少, 细胞器中呈先升后降的趋势, 而可溶性部分中无法测出。可见, Pb 打乱了各亚细胞组分中离子平衡, 导致愈伤组织正常生理活动紊乱, 这些都是Pb 毒害水花生愈伤组织的主要表现。       

淮南矿区大气及二球悬铃木叶片中重金属含量及其相关性分析

对淮南市污染区(矿区)和对照区(相对清洁区)空气中TSP、PM10-100、PM5-10、PM2.5-5和PM2.5的日均质量浓度进行了测定,并对TSP中Cd、Cr、Cu、Ni、Pb和Zn的质量浓度和二球悬铃木〔Platanus×acerifolia(Ait.)Willd.〕叶片中Cd、Cr、Cu、Ni、Pb和Zn含量的动态变化进行了分析,同时对二球悬铃木叶片中重金属含量与TSP中重金属质量浓度和各类空气颗粒物日均质量浓度的相关性进行了分析。结果表明:在60 d采样期内,空气颗粒物日均质量浓度和叶片中重金属含量均呈波动的变化趋势,其中污染区空气中TSP和PM2.5的日均质量浓度均显著高于对照区,污染区PM10-100、PM5-10和PM2.5-5日均质量浓度总体上低于对照区;污染区空气TSP中6种重金属元素的质量浓度均高于对照区,污染区二球悬铃木叶片中的Cd、Cr、Cu、Ni和Zn含量均高于对照区但Pb含量低于对照区。相关性分析结果表明:污染区二球悬铃木叶片中重金属含量与空气TSP中重金属质量浓度多数呈正相关,叶片中重金属含量与空气中PM2.5日均质量浓度也均呈正相关,其中叶片中Cd含量与PM2.5日均质量浓度的相关性达显著水平。研究结果表明:在淮南矿区,可将二球悬铃木叶片中的重金属含量作为空气PM2.5污染状况的监测指标。     

不同铅水平下紫茎泽兰细胞内铅的分布和化学形态的分析

该研究运用差速离心法和化学试剂逐步提取法,分析了重金属铅在紫茎泽兰亚细胞内的分布和主要化学形态。结果表明:随着Pb浓度的升高,紫茎泽兰的叶、根、茎中各亚细胞组分Pb含量逐渐增加;紫茎泽兰中的Pb在叶片分布于可溶性部分和细胞壁中,两者占总量的75.34%~84.63%;茎也主要分布于可溶性部分和细胞壁中,占总量的36.10%~57.14%和20.07%~36.52%;而在根中则富集于细胞壁和可溶性部分,分别占39.2%~49.78%和28.27%~37.62%,其他细胞器中的Pb含量均较少。紫茎泽兰叶中的Pb以盐酸提取态和水提取态为主,两者占总量的58.74%~73.04%;茎中的Pb以醋酸提取态和氯化钠提取态为主;而根中的Pb则以醋酸提取态和盐酸提取态占优势,两者占总量的39.15%~52.91%。     

复合胁迫下茭白体内镉、铅的亚细胞分布和植物络合素的合成

以茭白（Zizania latifoliaTurcz.）的单季茭品种‘蒋墅茭’和双季茭品种‘葑红早’为试材,进行Cd2＋、Pb2＋的单一及复合胁迫处理,测定了茭白根系和叶片中的非蛋白巯基（NPT）、谷胱甘肽（GSH）、植物络合素（PCs）的含量,同时测定了茭白植株各亚细胞组分中Cd2＋、Pb2＋的积累量,以探讨茭白对重金属镉、铅胁迫的耐性机理。结果表明：Cd2＋、Pb2＋的单一及其复合胁迫均能促进两茭白品种根系和叶片中NPT、GSH、PCs的含量及茭白各亚细胞组分中Cd2＋、Pb2＋积累量的显著增加;复合胁迫时两茭白品种的NPT、GSH、PCs含量及各亚细胞组分中Cd2＋、Pb2＋的积累量均高于单一胁迫,茭白的不同部位间,以根系中的NPT、GSH、PCs含量显著高于叶片;茭白各亚细胞组分中Cd2＋、Pb2＋的积累量表现为：细胞壁高于原生质体,而可溶性部分高于细胞器。     

南京市14种绿化树种对空气中重金属的累积能力

分析了南京化工厂（污染区）和江苏省林科院（对照区）不同绿化树种叶片重金属元素（Pb、Cd和Cu）的含量,揭示了14种绿化树种对3种重金属污染物的累积能力。结果表明,城市绿化树种对大气重金属污染物具有一定的吸收净化能力,并依重金属和树种的不同具有明显差异;同种植物对不同重金属的累积量也有很大差别,其中对Cu的累积量最高;采样区植物叶片重金属含量明显高于对照区;对Pb累积量高的树种有：杨树、广玉兰、女贞和紫叶李; Cd累积量高的树种为杨树;Cu累积量高的树种为构树;累积3种重金属综合能力最强的树种有杨树、构树、雪松、广玉兰、悬铃木、栾树。     

6种交通重金属污染物在悬铃木叶、枝条组织中的分布研究

以南京市常见行道树二球悬铃木为试材,通过对交通繁忙区和相对清洁区道路两边悬铃木叶和一年生枝条中6种重金属元素在组织水平分布的研究,揭示其在悬铃木各组织中可能的分布机理,以及对重金属可能的抵御机制。结果表明,置于空气污染下悬铃木叶片与一年生枝条各组织具有累积重金属元素的能力,且污染区相对含量高于清洁区（除Ni外）;叶片各组织累积能力大小为下表皮＞上表皮、海绵组织＞栅栏组织。悬铃木一年生枝条表皮因具有皮孔、表皮毛和蜡质,故也有一定的重金属累积能力;悬铃木表皮系统是重要的重金属吸滞组织,且累积于表皮的重金属元素可通过表皮进入皮层和髓,这与一年生枝条内重金属元素的运输途径有关,具体运输机理有待于进一步探讨。根据悬铃木各组织重金属的分布,认为叶片和茎的表皮系统更能反映空气污染的真实情况,且这两种材料采集容易、破坏性小,建议在空气污染监测中大力采用。     

铬污染人工湿地薏米对铬的积累和分布

通过桶栽构筑微型垂直流人工湿地,在生活污水中添加不同浓度的Cr~(6+)(0、20、40 mg·L~(-1),用K_2Cr_2O_7配置),研究了在铬(Cr)污染条件下薏米不同器官和亚细胞水平对铬的积累及分布。结果表明:薏米根茎叶铬含量均随铬处理浓度的提高和处理时间的延长而显著增加,根部铬含量最高,其次是叶片,茎部铬含量最低。随着铬处理浓度的增加和时间的延长,细胞壁和液泡中的铬含量大幅上升,但细胞器中铬含量上升幅度较低,根部细胞壁、细胞器、可溶部分及液泡铬含量均显著大于茎、叶相关细胞组分,根、茎、叶亚细胞水平铬含量分布均依次为细胞壁液泡细胞器。其中,细胞壁铬含量极显著大于液泡以及其他细胞器,薏米根部把大部分铬隔离在细胞壁中,从而降低了地上部分对铬的吸收,导致地上部分干重、鲜重的受抑制程度均低于根系,表明根部细胞壁是降低铬在薏米体内积累的重要屏障,也是薏米在低浓度铬胁迫下能够存活的根本保证。     

矿区道路两侧雪岭云杉叶片重金属富集效应

采矿及矿产品运输过程会对环境造成重金属污染进而对生物体产生危害。为定量描述艾维尔沟矿区道路两侧重金属污染程度、明确雪岭云杉叶片对重金属的吸收富集效应,通过采集雪岭云杉叶片和土壤样品,测试其铅(Pb)、锌(Zn)、镉(Cd)、砷(As)、铜(Cu)、铬(Cr)的含量,分析重金属的富集效应和空间分异特征。结果表明:(1)雪岭云杉叶片和土壤中各重金属含量差异显著(P0.05),叶片中Pb的含量显著高于其余重金属(P0.05),平均达86.28μg/g,土壤中Zn、Cu超过了国家土壤质量标准的一级限制值,而As比三级限制值大41%;(2)以背景区(板房沟林场)的土壤和雪岭云杉叶片重金属为评价标准,研究区雪岭云杉叶片重金属综合污染指数为2.05,属中度污染,其中As和Pb单项污染指数较高,达3.65和2.57。研究区土壤重金属综合污染指数为1.69,属轻度污染;(3)随距离增加,除土壤和叶片中Pb含量表现为负线性递减外,As和Cu均表现为先升高后降低,土壤中Cr、Zn逐渐升高,但叶片中Cr逐渐降低,Zn变化不大;(4)冗余分析(RDA)结果显示土壤中Cu、As、Pb与雪岭云杉死树胸径和树高呈正相关关系,而Cr、Zn与其呈负相关。采矿及运输已对土壤和雪岭云杉的生长造成影响,本文对天山雪岭云杉森林的生态修复与保育具有一定的借鉴作用。     

桉树对矿区污染土壤中Cu和Cd的耐受机制

为明确桉树对土壤中Cu和Cd的耐受机制,采用某矿区实际污染土壤进行盆栽实验,研究了桉树对Cu和Cd的吸收和累积,分析了桉树根、茎和叶中Cu和Cd的亚细胞分布。实验结果表明,随土壤污染程度的增加,重金属的转运系数降低,Cu和Cd滞留在桉树根部。重度污染土壤中,桉树根部的Cu和Cd分别占植株总量的43%和90%。随污染程度的增加,桉树根部Cu和Cd的含量先增加后稳定,重度污染土壤中,桉树根部Cu和Cd的累积系数降低,对Cu和Cd的吸收受到限制。桉树吸收的Cu和Cd主要分布在根、茎和叶的细胞壁组分(45%),随土壤污染程度的增加该比例大致保持稳定。重度污染土壤中,Cu和Cd在桉树根部可溶组分中的比例增加。综上所述,根部的滞留作用、根部的吸收限制、细胞壁固持作用及可溶组分的区隔化作用,是桉树耐受污染土壤中Cu和Cd的主要机制。     

Heavy Metal Contents in Tissues of Dominant Species of the Benthos and in Bottom Sediments of Zolotoi Rog Bay, Sea of Japan

Data on heavy metal contents in polychaetes and free-living nematodes inhabiting the bottom sediments of Zolotoi Rog Bay near the port of Vladivostok are reported. Chronically high contents of heavy metals (Fe, Cu, Zn, and Cd) were found in the bottom sediments and in the infauna. The levels of some toxic elements in tissues of the polychaete Dorvillea (Schistomeringos) japonica inhabiting polluted sediments of Zolotoi Rog Bay were higher than in worms of this species from relatively clean areas of the Sea of Japan. Similar high concentrations of Fe were found in the polychaete Capitella capitata and the nematode Oncholaimium ramosum. The highest concentrations of Fe, Zn, Cu, and Cd were found in tissues of the free-living nematode O. ramosum. Chronic heavy pollution of the bottom sediments leads to a decrease in the biodiversity of the infauna and to specific metal-tolerant communities.Original Russian Text Copyright © 2005 by Biologiya Morya, Davydkova, Fadeeva, Kovekovdova, Fadeev.     

杭州市六种常见绿化树种叶片累积空气重金属特征及与环境因子的相关性

该研究选取杭州市2个污染区常见的6种绿化树种叶片作为材料,以清洁区为对照,采用电感耦合等离子体发射光谱法,测定受试树种叶内及对应样点降尘、土壤中Pb、Cd、Cr、Cu、Ni和Zn的含量,分析叶片的吸污能力以及重金属含量与土壤、降尘的相关性。结果表明:(1)污染区树种重金属含量明显高于对照区,绿化树种对环境重金属污染物有一定的吸收能力,重金属含量在不同的树种中具有明显差异;所测树种叶内Zn含量最大,Pb次之,Cd最小,指示能力则以枸骨(Ilex cornuta)对Cd和Pb、圆柏(Juniperus chinensis)对Cu、茶花(Camellia japonica)对Ni、广玉兰(Magnolia grandiflora)对Zn为最强。(2)3个样点树种叶片与对应样点土壤、降尘中重金属元素含量的相关性分析和回归分析表明,叶片重金属含量与土壤重金属含量的相关性较小,而与降尘呈显著正相关。因此,绿化树种叶片作为空气重金属污染的累积器和监测器是科学合理的,且上述4种树种对杭州市空气中6种重金属污染的指示作用具有一定参考价值,可作为监测城市空气质量的特型树种。该研究结果为减少城市空气重金属污染提供了科学依据和理论支持。     

Evaluation of Environmental Quality of Atmosphere by Determination of Element content in Plants and Soils in Tianjin

165 plants and 40 soil samples were collected at seven areas in Tianjin. The analysis of sulphur and heavy metals in these samples showed the polluted degree of the air. It is indicated that the plants at smeltery (polluted industry area) contain Zn, Cu, Cd, Pb highest and NJ, S higher. The content of heavy metals in these plants were 3 to 11 times higher than that of the background value. In business-traffic area and park, the amount of Zn, Cu, Ni, Cd in the plants were 1.5 to 3.5 times higher than the background value. In the other area, such as culture-education area, road and suburbs, the pollution is not significant, and in the clean area (Panshan), all elements in the plants are the lowest. As to the soils in polluted industry area (Smeltery), the amount of Ph, Cu, Cd, Zn and S was 725, 348, 9, 3 and 14 times higher than that of the background value respectively. Among them, most of Pb, Cu were deposited in surface layer. In soil of business-traffic area, Pb, Cu, Cd, Zn and S were 2 to 10 times higher than the background value, and in the soil of clean area, all elements are also the lowest. The stomata of plants which were blocked by the particles going down from the air resulted in increase in the stamotal diffusive resistance and the order of the resistance in the different places are as follows: polluted industry areas > parks > business-traffic areas > road > clean areas. These results are in agreement with the polluted state of the plants and soils in above mentioned areas.     

道路边际土壤重金属分布格局的神经网络模拟——以现代黄河三角洲为例

在实地采样的基础上,应用MLP神经网络模型和GIS技术,对现代黄河三角洲3类不同道路两侧边际50m带状区域内的土壤重金属含量进行了逐栅格模拟.结果表明:东部和北部的自然保护区以及东北沿海地区道路边际土壤重金属含量较低,西南部人口密集区重金属含量较高.研究区道路边际土壤的Mn、Zn、Cr、Cu、Pb、Cd等重金属平均含量分别达到509.57、61.26、58.55 、32.40、26.07mg/kg和0.27mg/kg,Cd污染较为严重,其余金属含量均低于国家土壤环境质量I级标准.道路对其边际重金属的累积作用明显,但对环境尚未造成广泛和显著的危害.不同道路类型的土壤重金属含量高速公路RG>省道RS>县乡公路RX(除Pb外).在风向、土壤性质和地表植被覆盖等主要因素的影响下,道路边重金属含量在30m以内达到峰值,但因重金属扩散机理的差异,变化规律有所不同.     

Biological Cycles of Mineral Elements in a Young Mixed Stand in Abandoned Mining Soils

Phytoremediation as a sustainable and inexpensive technology based on the removal of pollutants from the environmentby plants is becoming an increasingly important objective in plant research.In this study,biological cycles of five nutrientelements(N,P,K,Ca,and Mg)and eight heavy metal elements(Fe,Cu,Zn,Mn,Cd,Ni,Pb and Co)were examined in youngpaniculed goldraintree(Koelreuteria paniculata Laxm)and common elaeocarpus(Elaeocarpus decipens)mixed standsin an abandoned mining area.We found that after vegetation restoration in abandoned mining areas,the organic matterand concentrations of nutrient elements were significantly increased and the heavy metal elements were significantlydecreased,the annual retention,uptake and return were 75.0,115.4,and 40.3 kg/hm~2 for nutrient elements,and 1878.0,3231.0 and 1353.0 g/hm~2 for heavy metal elements,respectively,with the utilization coefficient,cycling coefficient andturnover rate of 0.92,0.35 and 0.32 for nutrient elements,and 1.24,0.42 and 1.92 for heavy metal elements,respectively.Our results suggested that the vegetation restoration in abandoned mining areas had significant effects in improvingenvironmental conditions,enhancing soil available nutrients,and ensuring human health.     

The Distribution of Heavy Metals in Urban Street Dusts of Karak City,Jordan

Street dust samples from urban and suburban areas were collected from the city of Karak, Jordan, during the summer season of 2004. Samples were analyzed for their heavy metal concentrations (Pb, Cu, Zn, Ni, Fe, Cr, Cd, and Mn). The results showed that all heavy metals are higher in city urban areas than the surrounding suburbs. The distribution and concentrations of heavy metals in all areas show automobile originated sources such as emissions and wear and tear of automobiles were the main source of pollution. Despite the fact that the city of Karak and the capital Amman are under the same climatic conditions and same type of fuel used in both cities, the heavy metal concentrations of street dust samples were lower in Karak than Amman due to the lower traffic density.     

Biological Cycles of Mineral Elements in a Young Mixed Stand in Abandoned Mining Soils

Phytoremediation as a sustainable and inexpensive technology based on the removal of pollutants from the environment by plants is becoming an increasingly important objective in plant research. In this study, biological cycles of five nutrient elements （N, P, K, Ca, and Mg） and eight heavy metal elements （Fe, Cu, Zn, Mn, Cd, Ni, Pb and Co） were examined in young paniculed goldraintree （Koelreuteria paniculata Laxm） and common elaeocarpus （Elaeocarpus decipens） mixed stands in an abandoned mining area. We found that after vegetation restoration in abandoned mining areas, the organic matter and concentrations of nutrient elements were significantly increased and the heavy metal elements were significantly decreased, the annual retention, uptake and return were 75.0, 115.4, and 40.3 kg/hm^2 for nutrient elements, and 1 878.0, 3 231.0 and 1 353.0 g/hm^2 for heavy metal elements, respectively, with the utilization coefficient, cycling coefficient and turnover rate of 0.92, 0.35 and 0.32 for nutrient elements, and 1.24, 0.42 and 1.92 for heavy metal elements, respectively. Our results suggested that the vegetation restoration in abandoned mining areas had significant effects in improving environmental conditions, enhancing soil available nutrients, and ensuring human health.     

Spatial patterns,hotspot, and risk assessment of heavy metals in different land uses of urban soils (case study: Malayer city)

A study on identification of hotspots, spatial patterns, and risk evaluation of heavy metals in urban soils of Malayer city (Iran) was carried out. Fifty-nine composite surface soil samples were collected from six different land uses (urban parks, streets, and squares, boulevards, residential and agricultural areas) in Malayer city, and the total heavy metals were measured by atomic absorption spectroscopy. Average concentrations of Cd, Pb, Cu, and Zn, As, Cd, and Pb were 0.66, 15.51, 12.25, and 96.8 mg/kg, respectively. Among the six land uses, heavy metal contamination was heavier for street, while low contamination could be found for residential and urban parks. The spatial distribution of Pb in surface soil was similar to those of Cd, and Cu was similar to those of Zn with decreasing values from the central areas to the suburb. Also, there were several hotspots for studied heavy metals that Cd and Pb were mainly occurred in locations of heavy traffic in the city center and Cu and Zn in the west and northwestern in the city. The calculated result of risk evaluation showed that much of the city suffered from moderate to severe pollution by four of these heavy metals.     

湖南省主要水系底泥重金属污染特征及其生态风险评价

为全面了解湖南省主要水系底泥中重金属含量及其潜在生态风险,在湖南省内的湘、资、沅、澧以及洞庭湖5个主要水系共采集了75个位点的底泥样品,分析了重金属元素含量和来源分布特征,并采用地累积指数法、内梅罗指数法和潜在生态风险指数法对其污染程度和潜在生态风险进行评价。结果表明,As、Cd、Cr、Cu、Mn、Pb和Zn的平均含量分别为32.87、7.59、78.09、70.69、1182.60、85.64 mg/kg和482.44 mg/kg。湘江和洞庭湖的污染相对严重,底泥中重金属含量明显高于资江、沅江和澧水;相关性分析表明多种重金属具有相同污染来源;地累积指数评价结果显示,湖南省主要水系底泥中Cd为重污染水平,Zn为中度污染,Cu、Mn和Pb均为轻度污染,而As和Cr污染程度为清洁;内梅罗指数法评价结果表明,除Cr为轻度污染外,湖南省主要水系底泥中其他6种重金属污染均为重污染级别;潜在生态风险评价结果显示,湖南省总体潜在生态风险属于中等级别,各水系潜在生态风险大小顺序为洞庭湖>资江>湘江>澧水>沅江,重金属Cd的潜在生态风险级别为很强,其他重金属元素都属于轻微级别。