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1.
采用光照培养箱培养及原子吸收分光光度法,研究了不同浓度(10~100mg·L-1)Cu2+、Pb2+单一及复合污染后玉米幼苗体内各器官中积累与迁移的动态变化规律。结果表明,在单一污染条件下,Cu2+、Pb2+在玉米体内的积累量与重金属处理浓度和处理时间呈正相关,分布顺序为根〉茎〉叶,积累量为Pb2+〉Cu2+,根茎间迁移率随着处理浓度增高逐渐减小,茎叶间迁移率变化规律为先减小后增大;复合污染后,随着处理浓度和处理时间的增加,Cu2+、Pb2+在玉米体内的积累量逐渐增大,其中(100+100)mg·L-1浓度下30d处理时积累量达到最大值,Cu2+、Pb2+在玉米各器官中的分布规律为根〉茎〉叶,积累能力为Pb2+〉Cu2+,根茎间的迁移率表现为在10~20d时随浓度增高逐渐上升,30d时逐渐下降,而茎叶间的迁移率则表现为随处理浓度的增加先升高后降低。Cu2+、Pb2+复合污染后玉米体内Cu2+、Pb2+的含量均大于单一处理,Cu2+、Pb2+复合处理具有协同效应。实验结果也证明玉米是一种易富集Cu2+、Pb2+的作物。  相似文献   

2.
《土壤通报》2020,(1):221-226
土壤重金属生态毒理学研究已成为当今生态与环境科学研究的热点。土壤弹尾目跳虫作为土壤模式生物,在土壤生态毒理学和生态环境评估研究中已被广泛应用。研究通过跳虫(F. candida)的标准土壤实验,利用电子显微镜技术,初步观察到暴露于土壤中高Cu浓度(1000,3000μg g-1)下的跳虫细胞微绒毛变形、部分线粒体扩大变形并出现囊泡化现象,这可能会导致细胞组织新陈代谢功能减弱进而影响跳虫的生理行为;同时,在高Cu暴露浓度下跳虫细胞内A型颗粒物大量存在,且其环边逐渐减少、变得模糊,这说明Cu的存在可能使A型颗粒物的结构和成分发生变化并变为储存Cu的重要细胞器。  相似文献   

3.
采用盆栽试验研究3种钝化剂(粉煤灰、磷灰石和膨润土)对黑土中铜(Cu)的化学形态、生物积累和有效性的影响。结果表明:3种钝化剂能显著降低Cu污染黑土中水提取态(DW)、TCLP提取态和二乙基三胺五乙酸-三乙醇胺(DTPA-TEA)提取态Cu含量,其中以膨润土的效果最为明显;Tessier连续提取测定发现,3种钝化剂显著降低非残留态Cu(水溶态和交换态、碳酸盐结合态、铁锰氧化物结合态和有机结合态)含量(p<0.01),增加残留态Cu含量,表明3种钝化剂通过改变黑土中Cu的化学形态,降低了黑土中Cu的可淋失性和生物有效性;与对照相比,添加钝化剂能显著降低水稻地上部分的Cu含量(p<0.01),如在400Cu mg/kg处理的土壤上,添加2.5%的粉煤灰、磷灰石和膨润土使米粉中的Cu含量分别降低21.8%,22.7%和31.9%。土壤中可淋失态和生物有效态Cu的分析表明,钝化剂主要是通过改变土壤中Cu的化学形态,降低土壤中Cu的生物有效性,以降低Cu在水稻中的积累;试验表明,Cu污染土壤中施用钝化剂可以修复Cu污染,降低水稻Cu污染风险。  相似文献   

4.
为了探讨外源性重金属暴露对鱼类呼吸反应的影响,利用鱼类的呼吸参数的变化来预警水体污染。尝试以斑马鱼为实验生物,进行了5种重金属离子对斑马鱼的急性毒性实验;应用生物早期预警系统(BIO-SENSOR 7008),研究了斑马鱼在不同重金属浓度暴露1 h后的呼吸反应变化情况及预警结果。结果表明,Hg^2+、Cu^2+、Cd^2+、Zn^2+、Pb^2+等重金属对斑马鱼的96 hLC50分别为0.14、0.174、6.497、44.48、116.432 mg.L-1;安全浓度分别为0.014、0.017、0.65、4.5、11.6 mg.L^-1;应用呼吸参数的预警浓度分别为0.08、0.08、4.8、7.5、105 mg.L^-1。其中系列浓度Hg2+暴露下斑马鱼呼吸频率和呼吸强度都显著升高(F=2.75,P〈0.05;F=28.95,P〈0.01);Cu^2+、Cd^2+等暴露对斑马鱼呼吸频率和呼吸强度先升高再降低(P〈0.01);Zn^2+暴露则对斑马鱼呼吸运动具有显著抑制作用(P〈0.01);而Pb2+对斑马鱼呼吸强度影响较小(P〉0.05)。斑马鱼呼吸参数作为生物监测指标来预警水体Hg^2+、Cu^2+、Zn^2+等重金属污染较为敏感。  相似文献   

5.
以苏州市7个县市的水稻籽粒为研究对象,在2006年采集的449份水稻籽粒样品的基础上,分析了稻米中Cu、Pb、Cd、Cr和Zn的积累特征,并评价了样品的健康风险。结果显示,苏州市水稻籽粒重金属积累平均含量均不超标,但水稻籽粒Pb存在29.49%的样点超标率,Cu、Cd和Cr的超标样点一般在4个以下。单因子污染指数评价结果显示,水稻籽粒重金属元素污染指数高低顺序为Pb>Cr>Cu、Zn>Cd,其中昆山和吴江水稻籽粒受到Pb的轻度污染。综合污染指数评价表明,水稻籽粒重金属污染处于警戒线级别,且水稻籽粒的污染是由于Pb的积累量较高引起的,其中太仓和张家港两市水稻籽粒属于安全等级,昆山、吴中、相城和常熟处于警戒线等级,吴江风险较高。暴露风险评价结果显示,研究区存在水稻籽粒Cr暴露风险,而水稻籽粒Pb仅在个别县市暴露风险高,整体风险并不高。  相似文献   

6.
为探讨赤子爱胜蚓谷胱甘肽(GSH)和丙二醛(MDA)含量变化对重金属污染土壤生态毒性的指示作用,在试验室模拟条件下,利用人工土壤和自然土壤,研究了重金属含量与蚯蚓GSH和MDA含量变化的剂量效应关系。结果显示,在人工土壤试验中,Cu可诱导蚯蚓GSH和MDA含量上升,暴露2 d、7 d、14 d后,Cu浓度与蚯蚓GSH含量的相关系数分别为0.556、0.807和0.775,与MDA含量的相关系数分别为0.760、0.672和0.544,均存在显著的剂量效应关系(p<0.05)。自然土壤试验结果显示,赤子爱胜蚓的GSH和MDA含量与土壤Cu全量的偏相关系数分别为-0.830(p<0.001)和-0.599(p<0.05),与Cd全量的偏相关系数分别为-0.697(p<0.05)和-0.690(p<0.05)。同时发现,赤子爱胜蚓GSH含量变化对土壤重金属响应的敏感性要高于MDA。  相似文献   

7.
为分析抗生素与重金属单一及复合污染对土壤过氧化氢酶活性的影响,以三种兽用抗生素恩诺沙星(Enrofloxacin,ENR)、土霉素(Oxytetracycline,OTC)、磺胺二甲嘧啶(Sulfamethazine,SM2)和重金属铜(Cu)为目标污染物,采用高锰酸钾滴定法,研究其对土壤中过氧化氢酶活性的影响。结果表明,单一污染下,中低浓度的ENR各处理对酶活性有一定激活作用,最大激活率为5.52%;OTC处理组随着污染物浓度的增加,对酶活性的抑制作用增大,抑制率最大为8.36%;SM2处理初期,中低浓度处理组对酶有激活作用,最大激活率为7.46%,处理21 d,高浓度处理组对酶活性有显著促进作用,激活率为1.71%。Cu在第28 d时对过氧化氢酶活性表现为抑制。复合污染下,ENR与Cu复合污染组对过氧化氢酶活性的影响随污染浓度增加先抑制后激活;OTC与Cu处理第7 d,各浓度组与对照差异均不显著,14 d后,高浓度组产生抑制作用,抑制率最高为3.58%;SM2与Cu高浓度处理组在第7 d对土壤过氧化氢酶活性表现为明显激活作用,激活率高达10.00%,14 d后转为抑制作用,28 d时抑制率最高为4.49%。研究表明,单一污染下,抗生素对土壤过氧化氢酶的影响与其类型、暴露浓度以及暴露时间有关。复合污染下,抗生素和Cu的交互作用存在差异,表现为拮抗和协同两种作用,不仅与抗生素种类、复合污染浓度比例、暴露时间有关,还与抗生素和Cu配位反应产生复合物的比例有关。  相似文献   

8.
采用以体数、鲜重和叶绿素为测试指标的浮萍生长抑制试验(ISO20079),评价了Cu和乙草胺单一和复合污染的毒性效应。结果表明,cu和乙草胺单一污染对浮萍上述指标均具有显著的抑制作用,且Cu的毒性大于乙草胺。Cu和乙草胺对浮萍的联合毒性作用与浓度组合及暴露时间密切相关:当采用浓度1:1进行试验时,暴露时间为24h的相加指数(AI)为0.057,联合毒性为相加作用;暴露时间为48、96、168h的AI分别为0.193、0.509、0.783,为协同作用。而当采用毒性1:1进行试验时,暴露时间为24h的AI为-0.163,为拮抗作用;48h的AI为0.029,为相加作用;96、168h的A1分别为0.471、0.585,为协同作用。总的来说,随着暴露时间的延长,联合毒性表现为协同作用。  相似文献   

9.
农户室内污染物浓度相关性分析   总被引:1,自引:0,他引:1  
本文对单一燃料使用时农户室内不同污染物浓度变化的相关关系,以及使用不同炉灶类型的农户PM2.5日均平均浓度和CO日均浓度间的相关性进行分析,力求通过污染物之间的相关关系,用一种污染物的浓度预测其他污染物的浓度,简化在农村实地检测室内空气污染水平的复杂性。研究结果表明,燃煤农户室内CO与PM2.5(R=0.841,P<0.01),CO与SO2(R=0.8878,P<0.01)浓度的变化都显著相关,燃柴农户室内CO与PM2.5浓度的变化(R=0.869,P<0.01)也显著相关;由于烟道内CO和SO2的浓度受外界环境影响较小,其相关关系非常显著(R=0.9846,P<0.01);CO和PM2.5水平之间的相关性与炉灶类型和燃料类型有关。  相似文献   

10.
向日葵对土壤中铜的积累作用研究   总被引:1,自引:1,他引:1  
温室内不同Cu浓度添加土壤的向日葵盆栽试验表明,向日葵植株的部分生物学性状如地上部干物质量、地下部干物质量、最大单叶面积随土壤中Cu浓度的增加而降低,土壤中添加20mg/kgCu对向日葵根部生长抑制作用最大,而植物高度在添加100mg/kgCu浓度时最高。且不同Cu浓度处理下向日葵对Cu的积累能力不同,但植物各部分Cu含量均随土壤中添加Cu浓度的增加而增加,但在100mg/kgCu浓度处理下,向日葵对Cu的积累主要集中在根部,地上部分Cu含量很低,在200mg/kgCu浓度处理下,向日葵叶中Cu含量超过根部,达857±297mg/kg干重,Cu积累的叶根比达1.27,说明当土壤Cu浓度较高时,Cu在向日葵地上部有较高的Cu积累,集中收获植株地上部分,可移出土壤中的过多有效铜,但生长受到抑制。使用向日葵修复高浓度Cu污染土壤时,还需考虑采用其他手段接种根际微生物、转基因、设施农业环境工程技术等来增加其生物产量。  相似文献   

11.
The effects of cadmium and copper on larval metamorphosis and mortality of cultured Capitella sp Y were investigated. Metatrochophore larvae were exposed to 0.013 (control), 0.030, 0.080, 0.120, and 0.170 mg Cd L?1 and 0.017 (control), 0.025, 0.060, and 0.075 mg Cu L?1 for 34 days. Larval mortality significantly (p < 0.01) increased with increasing Cd and Cu concentrations (Kruskal-Wallis test), with similar effects for both metals for day 10 (LC50 = 0.035 mg Cd L?1 and 0.035 mg Cu L?1). Metamorphosis was inhibited in larvae exposed to the two metals in the absence of food, the effect of Cu being the most severe. This study suggests that Cd and Cu exposure could be harmful to early developmental stages of Capitella sp Y producing a delay in recruitment into natural populations.  相似文献   

12.
铜和草甘膦对蚯蚓的毒性效应研究   总被引:2,自引:1,他引:2  
污染物的交互作用及其生态毒理效应已成为环境科学研究的主要方向。含铜杀菌剂与除草剂草甘膦[N-(膦酸甲基)甘氨酸]是农业生产中常见的农药,其在土壤中共存可能造成复合污染。草甘膦中含有羧基、氨基、磷酸基等配位基团对重金属阳离子和有机阳离子有很强的络合能力,草甘膦可以影响重金属的生物有效性、毒性以及重金属在生物体内的积累。本文以赤子爱胜蚓(Eisenia fetida)为例,采用室内模拟试验,单一试验设置5个铜浓度25 mg·kg-1、50 mg·kg-1、100 mg·kg-1、200 mg·kg-1和400 mg·kg-1,5个草甘膦浓度25mg·kg-1、50 mg·kg-1、100 mg·kg-1、200 mg·kg-1和500 mg·kg-1,并以去离子水做空白对照;复合试验设置2个铜浓度(低铜浓度25 mg·kg-1和高铜浓度200 mg·kg-1)分别与5个草甘膦浓度(0、25 mg·kg-1、50 mg·kg-1、100 mg·kg-1和200 mg·kg-1)复合;每个处理3次重复,试验期为35 d。研究了铜和草甘膦的单一及复合施用对蚯蚓的亚急性毒性效应。单一毒性试验结果表明,蚯蚓对低浓度铜的响应不敏感,而较高浓度铜使蚯蚓生物量的相对增长率受到显著抑制(α=0.01,r2=0.570),且未出现死亡,并且随着铜浓度的增加蚯蚓体内铜含量显著增加(α=0.01,r2=0.905)。与对照相比草甘膦的添加对蚯蚓的生长无显著影响。复合毒性试验结果表明,草甘膦和铜复合可以降低蚯蚓对铜的吸收,特别是当铜浓度较高时即200 mg·kg-1,草甘膦和铜复合可显著降低蚯蚓对铜的吸收,并且草甘膦能够减轻铜对蚯蚓生物量相对增长率的抑制,但差异并不显著。以上结果表明,铜比草甘膦的毒性大很多,铜与草甘膦复合能够减少蚯蚓对铜的吸收,缓解铜的毒性。因此本研究认为,在草甘膦和重金属共存的污染土壤中,草甘膦能够控制重金属的生物有效性和毒性。  相似文献   

13.
The contents of potentially toxic elements lead and cadmium and the essential element copper in various milk and dairy products consumed in Turkey were determined by differential pulse polarography (DPP), primarily to assess whether the intakes comply with recommended desired concentrations for essential and permissible levels for toxic elements. A simple and rapid DPP method has been developed for the simultaneous determination of cadmium, lead, and copper in samples. Using the differential pulse mode, half-wave peak potentials as E(1/2) were -0.58, -0.40, and -0.07 V for cadmium (Cd), lead (Pb), and copper (Cu), respectively. Marketed formulations of dairy products have been analyzed by calibration and standard addition methods. Recovery experiments were found to be quantitative. The linear domain ranges were 0.00-674.28 microg/L for Cd (R2 = 0.9999), 0.19-2.94 mg/L (p < 0.01) for Pb (R2 = 0.9997), and 0.41-133.46 microg/L for Cu (p < 0.01) (R2 = 0.9999). The studies have shown that the method is a rapid, reproducible, and accurate determination of these elements in milk and dairy products and can be used in the analysis of marketed formulations in the milk and dairy industry.  相似文献   

14.
为了探明温度对红色型豌豆蚜的世代累积效应,为利用生态措施防治豌豆蚜提供理论依据,本研究在人工设置的5个温度条件下(12℃、17℃、22℃、25℃和28℃)调查了红色型豌豆蚜连续3代的生长发育、繁殖力及生命表等。研究结果表明:红色型豌豆蚜在12℃时F_2代的若虫期较F_0和F_1代分别缩短16.0%和6.8%,而22℃和25℃下若虫期在3代间无显著差异;12℃时世代历期在F_2代较F_0和F_1代分别缩短10.5%和12.4%,17℃、22℃和25℃条件下世代历期在3代间差异不显著。在12℃下红色型豌豆蚜F_2代平均产蚜量较F_0和F_1代降低;而在持续高温25℃条件下后代繁殖力下降幅度最大,F_1和F_2代平均产蚜量较F_0代分别下降49.3%和50.9%,22℃下F_1和F_2代产蚜量与F_0代无显著差异。连续饲养红色型豌豆蚜,其成蚜体重在12℃和25℃下受影响最小,体重在3代间无显著差异;22℃下F_1代成蚜体重显著高于F_0和F_2代,12℃时体质量增长率有随代数增加逐代增长的趋势。随世代数增加红色型豌豆蚜在12℃和25℃条件下净增殖力(R0)降低、平均世代周期(T)缩短;25℃时F_1和F_2代的内禀增长率(rm)和周限增长率(λ)都较F_0代显著增长。表明在连续较低温或较高温胁迫下,红色型豌豆蚜后代繁殖力下降,体重无明显变化,但发育历期缩短,内禀增长率和周限增长率增长,表现出极强的环境适应能力,这可能是其种群数量上升的原因之一。  相似文献   

15.
Hydrocarbons and 2-alkylcyclobutanones in sesame seeds ( Sesamum indicum L.) irradiated at 0.5-4 kGy were used to determine the effect of subsequent steaming, roasting, and oil extraction from the roasted samples on the changes in their concentrations. The concentrations of radiation-induced hydrocarbons increased almost linearly (R(2) = 0.8671-0.9953) with the applied dose. The hydrocarbons, 1,7-hexadecadiene and 8-heptadecene, were detected only in the irradiated samples before and after three types of treatments at doses > or =0.5 kGy, but they were not detected in non-irradiated samples before and after treatment. These two hydrocarbons could be used as markers to identify irradiated sesame seeds. The concentrations of the three detected 2-alkylcyclobutanones, 2-dodecylcyclobutanone (2-DCB), 2-tetradecylcyclobutanone (2-TCB), and 2-(5'-tetradecenyl)cyclobutanone (2-TeCB), linearly increased with the irradiation dose. These compounds could be detected at doses > or =0.5 kGy but not in non-irradiated samples. The three types of treatments had no significant effect on the levels of 2-alkylcyclobutanones.  相似文献   

16.
This study was carried out to investigate the levels of copper (Cu) contamination in coffee fields in Kilimanjaro and Arusha regions, Tanzania, to increase the database on the contamination of soils by Cu-based fungicides in coffee fields. Surface (0–20 cm deep) soil samples were collected from different farms in Kilimanjaro and Arusha regions. Coffee, banana, and bean plant samples were collected from the locations of soil sampling. Soil and plant samples were analyzed at the Department of Soil Science, Sokoine University of Agriculture, Morogoro, Tanzania. It was found that the calcium chloride (CaCl2)–extractable Cu was less than the detection limit of flame atomic absorption spectrometry. Diethylenetriaminepentaacetic acid (DTPA)–extractable (24 to 366 mg Cu kg?1 soil) and aqua regia–extractable (80 to 806 mg Cu kg?1 soil) Cu levels were high enough to raise environmental alarm (based on European Union guidelines) in the Cu fungicide–treated soils as compared with natural Cu levels in untreated soils (1 to 12 mg Cu kg?1 soil for DTPA and 22 to 32 mg Cu kg?1 soil for aqua regia–extractable Cu). Coffee, banana, and bean plants grown on soils contaminated by Cu fungicides had varied concentrations of Cu that were greater than the concentrations of Cu in the plants collected from the uncontaminated soils. Stepwise regression analysis carried out to investigate the relationships between the soil properties and the concentrations of Cu in plants revealed a significant (P = 0.01) positive relationship (R2 = 0.4) between organic carbon and the concentration of Cu in banana leaves. Aqua regia–extractable Cu was positively correlated (P = 0.03, R2 = 0.4) with the concentrations of Cu in banana leaves. For bean leaves, electrical conductivity (EC) had a positive significant (P = 0.01) relationship (R2 = 0.56) with the concentrations of Cu in the plants. It is recommended that further research be carried out to investigate the dynamics and bioavailability of Cu for the different crops interplanted in the coffee fields.  相似文献   

17.
ABSTRACT

Presence of copper (Cu) and fluorine (F) in soils pose a risk of food web contamination when crops are grown on such soils. Greenhouse experiments involving 34 soil samples were carried out to explore the uptake of F and Cu by lettuce (Lactuca sativa L.). Each soil sample was divided into two parts. One set was irrigated with tap-water and another set was irrigated with F-contaminated water. Lettuce plants were grown for 60 days then harvested. Data were analyzed using stepwise regression analysis, t- or F-tests. Soils contained elevated concentrations of F and low to high concentrations of Cu. Soluble fractions of F were higher than reported values from other studies. It was observed that the soluble F or Cu contents in F-contaminated irrigated soils were significantly higher than the F or Cu contents in tap-water irrigated soils. Concentrations of F in lettuce were higher than normal F concentrations in plants. Soil EC was negatively related with the concentration of Cu in lettuce. A negative relationship occurred between the concentrations of F and Cu in the lettuce plants, signifying that the two pollutants have antagonistic relationships. The lettuce irrigated with F? contaminated water, accumulated higher concentrations of F than the lettuce irrigated with tap water, indicating that the F-contaminated water irrigated lettuce was more contaminated than the tap-water irrigated lettuce.  相似文献   

18.
Dendrobaena veneta is an earthworm species capable of consuming a wide range of organic wastes which may be used as a field indicator of municipal sewage sludge applied to land. The aim of the present 8-week laboratory experiment was to check viability, reproduction and the immune system of D. veneta maintained in soil without food additions (control 0s group) or in soil amended with 25% or 50% municipal sewage sludge (25s and 50s groups, respectively). Reproduction and immunity are important physiological functions whose detailed study can provide information on the effects of pollutants. After the 8-week exposure period, earthworm mortality (2 out 20 individuals) was recorded only in the 50s group. Reproduction was high in the 25s group (44 cocoons and 41 juveniles) whereas reproduction was almost completely inhibited both in the food-deprived control 0s group (1 cocoon, 3 juveniles) and in the 50s group containing a high amount of sludge (2 cocoons). Significantly increased numbers of non-invasively extruded coelomocytes were recorded 3 weeks after the start of the experiment in the 50s group, but they dropped to the food-deprived control level by the end of 8 weeks likely due to exhaustion of the immune system coping with sludge-derived microbes and/or toxins. In contrast, numbers of coelomocytes in the 25s group increased gradually reaching the maximum at the end of the experiments. In conclusion, high amounts of municipal sewage sludge are detrimental to worms, inhibiting reproduction and inflicting mortality. A moderate amount of municipal sewage sludge provides a good source of nutrients for D. veneta, supporting their growth and reproduction for at least 8 weeks. Immunological parameters might serve as useful indicators of earthworm exposure to sewage sludge.  相似文献   

19.
Population-specific differences in the responses of earthworms to simultaneous exposure to Cu and Zn were studied in microcosm experiments. Two populations of Aporrectodea caliginosa tuberculata (Eisen) with different metal exposure histories were chosen for the studies. Microcosms were prepared containing either uncontaminated soil or soils with low or high combined Cu/Zn -concentrations (79/139 or 178/311 mg kg−1 dry mass of soil, respectively). Earthworms from each population were introduced to the microcosm treatments with some microcosms serving as controls without earthworms. One series of microcosms was destructively sampled after 16 weeks incubation in a climate chamber. Survival, growth, reproduction and decomposition by earthworms in each treatment were measured. An additional microcosm series was sampled for soil and earthworm measurements at four weeks intervals to determine temporal changes in the availability of metals in the soils and their accumulation into earthworms. Cu and Zn were sequentially extracted from the soil samples of both microcosm series to estimate mobility and availability of the metals in the soil. Earthworms with long-term exposure history to metal-contaminated soil seemed to tolerate higher soil metal concentrations than earthworms without earlier exposure. Both earthworms and metals affected soil respiration (CO2 production) and nitrogen mineralization. In addition, earthworms seemed to decrease the mobility and bioavailability of metals in the soil through their burrowing activity.  相似文献   

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