浅析土壤环境中的镉的影响

由于工业的污染使土壤中镉的含量增加,从而直接导致对食物链的影响,文章以镉为例,进行研究.而研究高等植物是生态系统的重要组成部分,一个平衡、稳定的生态系统生产健康、优良的高等植物.因此,利用高等植物的生长状况诊断土壤污染,是土壤毒理诊断的重要方法之一.     

恐怖事件中恐怖分子常用化学武器的分类

为了作好"反恐怖"工作,必须了解和掌握恐怖分子采用的武器性能,文章简要介绍了恐怖分子所使用的四种化学武器的性能、毒性、毒物的初步识别等方法.     

试析我国湿地的退化、保护与恢复

湿地是地球表层最具独特的生态系统和过渡性景观,是地球表层系统最重要的"物种基因库",又是人类重要的经济、文化、科学和生活资料库.世界保护大纲将湿地与森林、海洋一起并列为全球三大生态系统.20世纪70年代以来,全球性的湿地消失和退化危机引发了严重的生态环境和社会问题,直接威胁到区域、国家乃至全球的可持续发展.本文从湿地的界定开始,分析了我国湿地的退化、保护与恢复,相信在我国政府和人民的共同努力下,我国湿地一定会恢复往日的景象.     

殡仪馆环境污染物分析

殡仪馆存在的环境污染问题日益受到公众和环保工作者的重视,其中以空气中存在的致病菌和遗体火化产生的废气为主.监测殡仪馆环境中存在的细菌总数以及遗体火化所排放的NOx,SO2,CO等污染物,并对采取控制措施前后的监测值进行对比,为治理殡仪馆环境污染,保护殡葬职工和死者家属的健康提供了科学依据.     

北方中小城市园林绿化中存在的问题及建议

进入新世纪,国家对生态环境越来越重视,城镇建设必须与生态环境相协调,走可持续发展的道路.城市绿化在改善生态环境方面具有巨大作用.在此就城市园林绿化过程中存在的问题及如何搞好城市园林绿化作了充分的阐述,希望对园林绿化工作的开展起到积极推动作用.     

典型飞机内腔结构腐蚀原因分析及防腐改进

以典型飞机平尾大轴为例,分析了内腔结构发生腐蚀的主要原因.围绕内腔结构防腐改进技术措施开展深入研究,研制成功了适用于细长内腔无气喷涂设备.应用SLF重防腐涂层和IMR纳米复合涂层替代现有内腔结构防护涂层,提高了防腐涂层抗环境腐蚀性能.采用DL-609厌氧胶对平尾大轴进行密封处理,有效地阻隔了腐蚀介质进入内腔.按照所建立的方法对典型飞机平尾大轴实施了腐蚀修理与防护处理.检查结果表明,内腔表面防腐状况有了明显改善.     

铅盐生产企业对周边生态环境的影响

通过连续多年的系统监测和分析,研究了小型铅盐生产企业对周边大气、水、土壤、河流底质和农作物等生态环境的影响.研究发现,生产车间和距其100 m以外的居民区大气中铅尘分别超标548倍和4倍;500 m以外的农田土壤中铅超标1.26倍;雨水排放口附近河道水质中铅超标1.08倍;雨水排放口附近及下游800 m处的河道底质中铅分别超标1.99倍和1.33倍;500 m以外种植的小麦籽粒中铅超标16.5倍.环境污染的程度与距污染源的空间距离呈负相关.在此,还对小型重金属生产企业的环境监测和防止污染的转移提出了建议.     

诺砂试制经济型地面砖的研究

论述了对诺砂采用压制成型法试制低成本地面砖的工艺流程、试验过程及其结果分析,并对其反应机理进行了简单的探讨,为诺砂的综合利用提供了一定的参考.     

新知

1废水发电机根据Broadbent的统计,1栋7层高的楼房安装这台废水发电机后可以每年节省1000美元的电费。在不久的将来就会进入消费市场了。2蜂巢轮胎     

天津市领导出席国务院节能减排天津分会场会议

9 月27 日,国务院召开节能减排工作电视电话会议.天津市委常委、常务副市长杨栋梁,副市长王治平出席天津分会场会议并讲话. 杨栋梁、王治平指出,温家宝总理在此次电视电话会议上所作的重要讲话,站在全局和战略的高度,对下一步做好节能减排工作提出明确要求,进行了系统部署.全市各区县、各部门、各单位要深入贯彻落实,把节能减排作为调整产业结构、转变发展方式的重要抓手,认真分析当前形势,进一步加大工作力度,确保圆满完成全年节能减排目标任务,保证"十二五"节能减排工作开好局、起好步.     

深圳市冬、夏两季大气中有机氯农药的研究

利用大流量主动采样器,选择深圳市13个有代表性采样点,于2009年12月~2010年1月和2010年6月,分2个采样时期对深圳市大气中有机氯农药(OCPs)进行监测.结果显示,深圳市冬、夏大气中,13个点位总有机氯农药浓度变化范围分别为742~3522 pg/m3(平均值1769pg/m3)和507~2197pg/m3(平均值1163pg/m3).冬季大气中有机氯农药主要是DDTs、林丹、七氯、氯丹、六氯苯,占有机氯农药总量的87%;夏季大气中有机氯农药主要为DDTs、氯丹、林丹,三者总量占有机氯农药的89%.研究表明,深圳市大气中存在“新”DDT的输入,认为工业DDT是其主要来源,而γ-HCH以及氯丹的高检出与林丹和用于杀灭白蚁的氯丹的继续使用有关.     

北京东南化工区土壤有机氯农药污染特征和分布规律

采集北京原东南化工区表层土壤样品,测定了土壤有机氯农药(滴滴涕、六六六和六氯苯)残留浓度,结果表明化工区土壤有机氯农药浓度较高,滴滴涕和六六六平均浓度高达5470ng/g和2110ng/g,比一般农业和城市土壤中的浓度高出很多;某些点位甚至超过国家土壤三级标准,高浓度的点位主要集中在原农药厂的生产车间和存储点。六氯苯由于来源和挥发性跟滴滴涕和六六六不同,所以六氯苯残留在化工区土壤中的分布相对比较均匀。化工区土壤滴滴涕和六六六的异构体组成特征表明工业区土壤的有机氯农药降解速度较慢,滴滴涕残留来源于工业滴滴涕和三氯杀螨醇,而六六六主要来源于工业六六六。化工区的有机氯农药污染主要来自于原农药厂的生产和存储,重污染点位对周围化工厂的有机氯残留有一定的影响。由于高残留浓度和较低的降解速度,化工区土壤有机氯农药残留的环境风险值得进一步关注。     

Upper Yellow River air concentrations of organochlorine pesticides estimated from tree bark, and their relationship with socioeconomic indices

Organochlorine pesticide(OCP) concentrations in tree bark from the upper Yellow River region were determined. Total OCP concentrations ranged from 2.7 to 82 ng/g dw, with a mean of 20 ng/g dw. Concentrations of total(Σ) DDTs(0.49–37 ng/g dw), HCHs(0.55–4.5 ng/g dw), and HCB(0.1–1.0 ng/g dw) were much higher than the other OCPs and accounted for 89% of the ΣOCP concentrations. p,p′-DDT was the dominant member of the DDT pesticide group and-HCH was the dominant HCH isomer. The p,p′-DDT/p,p′-DDE and-HCH/-HCH ratios suggested that there were recent DDT and-HCH releases. OCP concentrations in the air were estimated from the tree bark, and the estimated median ΣDDTs, ΣHCHs, and HCB concentrations in the air were 0.09, 0.14, and 0.024 pg/m3, respectively. The relationship between total OCP concentrations and socioeconomic and natural environment indices were assessed using multiple linear regression analysis, and a regression equation including all these factors was obtained. Population density and tertiary industry were the two dominant factors that appeared to affect OCP concentrations in the upper Yellow River region.     

苏州、无锡和南通城市地表灰尘中的有机氯农药

2009年7月在江苏省南部城市苏州,无锡和南通采集了58个城市地表灰尘样品, 使用加速溶剂萃取、气相色谱质谱法测定了样品中的22种有机氯农药(OCPs).结果表明,样品中有19种OCPs被检出,总OCPs含量为76.6mg/kg.六氯苯(HCB)、总滴滴涕(DDTs)和氯丹是样品中检测出的主要OCPs,检出率分别为100%、100%和82.8%,含量分别为26.8mg/kg(0.432~348mg/kg)、39.6mg/kg(1.95~559mg/kg)和6.17mg/kg(ND~145mg/kg).城市地表灰尘样品与中国城市大气样品中检测出OCPs的种类基本一致,而各化合物之间的比例不同.与郊区农田土比较,地表灰尘中检测出的OCPs种类多且含量高.样品中(DDD+DDE)/DDTs的比值显示地表灰尘中的DDT大部分已经降解.城市地表灰尘中的HCB含量较高,工业污染来源可能性较大,工业污染源释放的HCB已经通过大气传输影响到了城区.城市地表灰尘中的反式-氯丹与顺式-氯丹的比值平均为1.94,表明城市中仍有新近使用氯丹的现象.     

Levels and distribution of brominated flame retardants in the soil of Harbin in China

This study reports the presence of brominated flame retardants in the topsoil in and around Harbin, a city in northeastern China. Samples of soil were collected from 17 locations in 2006, and the levels of 9 polybrominated diphenylethers (PBDEs 17, 28, 47, 66, 99, 100, 153, 154, and 183) ranged from 2.45 to 55.9 pg/g dry weight (dw) with a mean of 26.3 pg/g dw. These levels are very low comparing with those for some cities in Europe and USA. BDE 209 and hexabromocyclododecane were the two dominant congeners, with mean concentrations of 520 pg/g dw and 1750 pg/g dw, respectively. The concentrations of the total nine PBDE congeners clearly decreased from urban areas to background, but the compositions of individual congeners di ered. Proportions of heavier congeners decreased while those of lighter congeners increased, along urban-rural-background transect, providing evidence for an urban fractionation e ect. Correlation analysis indicated similar sources for PBDEs, hexabromocyclododecane, and 1,2-bis(2,4,6-tribromophenoxy)-ethane from urban areas but pentabromoethylbenzene was probably present due to long-range atmospheric transport. Principal component analysis was used to determine the characteristics of the relationships among these brominated flame retardants in the field.     

地下河流域土壤中有机氯农药分布及来源分析

为研究有机氯农药在重庆青木关地下河流域土壤中的分布特征及来源,采用GC-μECD对17个代表性表层土壤样品进行分析.结果显示,研究区土壤中OCPs的含量范围是7.29~222.42ng/g,平均值为46.15ng/g.HCHs、DDTs在所有样品中均有检出,HCHs的含量范围是0.55~26.54ng/g,DDTs的含量范围是4.31~213.50ng/g.HCB的检出率达到88%,其含量范围是n.d.~1.78ng/g.研究区土壤中HCHs可能来源于工业HCHs残留和林丹的混合源,且由于环境影响,土壤中HCH的同系物之间发生了明显变化.DDTs主要来源于工业DDTs的非法使用,而非三氯杀螨醇类型的DDTs,并且仍有新的DDTs输入.与国内其他地区同类研究相比,本研究区土壤中HCHs、DDTs的残留水平较低;与国外相关研究相比,研究区内土壤中HCHs和DDTs的含量均高于德国、埃及、罗马尼亚土壤中HCHs和DDTs的含量.     

土壤及果树中HCH和DDT残留及分布规律研究

采用索氏提取、弗罗里土固相微萃取小柱净化结合GC-ECD测定了苹果园土壤和果树样品中4种六六六(HCH)和4种滴滴涕(DDT)的残留量,并对果树的根、枝、叶中HCH和DDT的分布规律进行了研究。实验结果表明,土壤和果树样品中均有HCH和DDT检出。土壤样品中两类农药的含量分别在0.51～3.97ng/g和1.46～15.55ng/g之间,其中β-HCH是六六六残留的主体,滴滴涕类的含量以p,p'-DDT为最高,并且(DDE+DDD)/DDT<1表明近期果园中有新的DDT输入。果树样品中,HCH和DDT的残留量分别在0.22～2.01ng/g和0.38～6.08ng/g之间,都要低于相应土壤中有机氯农药的浓度。果树中总OCPs的含量在4.88～17.94ng/g之间,是土壤和大气中OCPs污染共同作用的结果。根部的OCPs的含量明显高于枝和叶,其分布规律为根>叶>枝,这主要取决于根、枝、叶各组织的结构以及农药的理化性质。     

江汉平原中部表层土壤中有机氯农药分布及来源

以GC/ECD测定江汉平原中部24个表层土壤中25种有机氯农药的含量。所有有机氯农药均有检出,其中含量最高的是DDT类农药,HCHs类农药含量规律为δ-HCH>α-HCH>β-HCH>γ-HCH。研究区域农药含量较国内其他地方来说污染较低。通过成分的不同含量比较,发现该地区农药除了早期污染外,近期也有新的污染源。     

Passive air sampling of organochlorine pesticides in a northeastern state of India, Manipur

Thirty-six polyurethane foam disk passive air samplers (PUF-PAS) were deployed over a year during January to December, 2009 at three locations, i.e., Imphal (urban site), Thoubal (rural site) and Waithou (alpine site) of Manipur, to assess the seasonal local atmospheric emission of selected organochlorine pesticides (OCPs). The average concentration of HCHs monitored at mountain site during hot season (Mar, Apr, and May) and rainy seasons (Jun, Jul, Aug, and Sep) were 403 and 349 pg/m3, respectively. DDTs had a high concentration with 384 pg/m3 at rural site and 379 pg/m3 at urban site during hot seasons. Endosulfans and chlordane were found high in concentration during hot seasons (260 pg/m3) and low during retreating monsoon seasons (44 pg/m3) at rural site. Most of the OCPs concentrations were high during cultivation period. The OCP concentrations of rainy season were highly correlated (p < 0.01) with OCPs of hot seasons. Further, positive correlation (p < 0.05) was also obtained between cold seasons and retreating monsoon. Principal component analysis showed a significant correlation among the four seasons and distribution pattern of OCPs in air. Back trajectory analysis by using HYPSLIT model showed a long range air transport of OCPs to the present study area. Present OCP levels at Manipur is an outcome of both local emission and also movement of air mass by long range atmospheric transport.     

Organochlorine pesticides in soils under different land usage in the Taihu Lake region, China

A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field ＞ tree land ＞ fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT ＞1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.