应用污染负荷指数法评价攀枝花地区金沙江水系沉积物中的重金属

本文对攀枝花地区金沙江水系沉积物中8个重金属元素的地球化学特征、空间分布特征进行了研究,并应用污染负荷指数法对各重金属的污染程度进行了评价。研究发现,重金属在支流与金沙江交汇点下游处含量高于上游处,重金属污染不严重,属轻度污染。污染程度为:Mn>V>Pb>Zn>As>Cr>Cu>Co。污染较严重的是攀钢冶金区、攀钢选矿区、攀钢采矿区以及攀钢尾矿坝。     

成都地区蔬菜中重金属污染分析与评价

通过对成都地区的9种蔬菜152个样品的可食部分中重金属元素的分析研究，查明了蔬菜中重金属汞、砷、铅、锡的含量及分布特征。结果表明，锡和铅是成都地区蔬菜中的主要污染元素，在检测的蔬菜样品中，锡和铅的超标率分别为29．4％和22％，最高超标分别为5.60倍和2.86倍，汞和砷无超标现象。     

河南农田土壤重金属污染状况及其评价

在河南境内取自农田土壤102例表层样品，分析了其中的Cr、Zn、Cu、Pb、Ni、As等8种重金属元素的含量。结果表明：河南农田土壤中除Cr偶有超出我国《土壤环境质量标准》（GB15618—1995）二级标准的土样外，其他项目均不超标，重金属污染由高到低排序为Cr〉Zn〉Ni〉Cd〉Hg〉Cu〉Pb〉As。重金属元素在河南各土壤利用类型中分布规律不明显，按4种主要土壤利用类型考查来看，重金属污染程度大小排序为：果园地〉水田〉菜地〉其他粮田；河南农田土壤综合污染指数总平均为0．981，土壤总体为尚清洁，重金属污染处于警戒水平；河南农田土壤中Cr含量较高的土壤主要是粗骨土与石质土，其天然本底值较高。     

龙湾涌沉积物重金属污染现状评价

本文根据广州市番禺区龙湾涌沉积物重金属的调查结果,分析了沉积物重金属含量的空间分布,表明龙湾涌沉积物重金属含是沿河分布的差异与水流速度、工业排污位置有关,采用重金属潜在生态危害指数法评价了龙湾涌重金属对水生态系统的潜在危害,结果表明：产生生态危害的主要重金属污染物为Hg;其次为Cd、Cu、Pb、Cr、Zn。污染最严重断面是龙湾闸口,龙湾涌重金属潜在污染除龙湾闸口沉积物Cd属中等生态危害外,龙湾涌生态危害属于轻微。     

会理污灌区重金属污染的调查,评价及防治对策

本文调查、评价了会理县锌矿污灌区内水、土、作物的重金属污染状况。调查结果表明：污灌区内土壤、作物重金属污染严重,尤以镉污染突出。作物中镉含量与距污染源距离呈负相关（ｒ＝－０．９９５）。镉在水稻植株各部位的分布,以根系含镉量最高,茎叶次之,谷粒最少。评价结果表明农灌水的污染程度不大,土壤中Ｃｄ、Ｚｎ、Ｐｂ污染是土壤污染的主要表现,水稻的污染较玉米更为严重。Ｃｄ已对人体健康构成潜在危害。本文还针对污染区的重金属污染提出了相应的防治措施     

电镀废水污染区土壤重金属含量的测定及污染状况评价

运用原子吸收光谱法,测定了某地电镀废水污染区重金属污染土壤样品中cd、Ph、cu、zn4种元素的含量,RSD小于1％,加标回收率在92．78％-103．2％之间,表明测定结果可靠。依据测定数据、国家土壤环境质量二级标准、内梅罗指数法及潜在生态危害指数法,对电镀废水污染区土壤重金属污染状况进行评价。按二级标准评价结果为中度以上污染;以内梅罗综合污染指数法进行评价,土壤受到重度污染;用潜在生态危害指数法对污染生态风险进行评估,总潜在生态风险程度为重度。因此应对该区污染土壤进行治理。     

某搬迁铜冶炼企业原址用地土壤重金属污染空间分布特征及风险评价

文章以某搬迁铜冶炼企业原址的核心生产区作为研究区域,共采集土壤样品816份。在详细调查研究区域土壤重金属污染状况的基础上,通过单因子污染指数法、内梅罗综合污染指数法和潜在生态风险指数法对研究区域土壤中的重金属污染状况和潜在生态风险进行了风险评估。运用统计分析结合地理信息系统（GIS）插值方法研究了该场地土壤中重金属污染的空间分布特征,结果表明：研究区域内土壤受到砷（As）、铅（Pb）、钴（Co）、镉（Cd）和铜（Cu）五种元素不同程度的污染;单因子污染指数Pi最大值由大到小依次为As>Cd>Pb>Cu>Co。内梅罗综合污染指数评价结果表明,研究区域内污染在空间分布上呈集中趋势,而且随着地层深度的增加,污染占比和污染等级均呈下降趋势。潜在生态风险评价结果显示,研究区域内As和Cd存在极强潜在生态风险;Pb的潜在生态风险等级为强;Cu和Co为中等潜在生态风险。随着地层深度的增加,各风险等级占比均逐渐降低。研究区域总体呈现自上而下污染面积逐渐减小、污染浓度逐渐降低的趋势,其中土壤As的污染情况最为严重和普遍。     

应用地积累指数法和生态危害指数法对关中西部某铅锌冶炼区周边土壤重金属污染评价

采用近年常用于重金属污染的地积累指数法及生态危害指数评价法对关中西部某铅锌冶炼区表层土壤中重金属污染情况进行了评价.结果表明,两种方法均能对人为污染行为作出较为科学的评价,且两种方法可得到相似的评价结果:该冶炼区周边土壤Cd元素为中重度污染,Pb为中等污染,Zn和Cu为轻微污染.生态危害指数评价法和地积累指数评价法两种方法都是基于沉积学理论提出,两者各有侧重点,对于重金属污染的系统评价各具合理性;但在对土壤重金属污染进行评价时,有一定的局限性,建议在修正其参数后综合应用.     

唐岛湾岔河入海口沉积物重金属污染研究

在唐岛湾岔河入海口三角洲采集表层沉积物,采用X射线荧光光谱仪分析法检测Cu、Zn、Pb、Cd、Hg、As、Cr等共计7种重金属元素的含量。利用地累积指数法(J_(geo))及潜在生态危害系数法(ERI)对其重金属分布特征、潜在生态危害进行分析评价,结果表明:岔河入海口地区重金属污染整体较低,呈现出南北高中部低,且北部高于南部的分布特征,三角洲北部靠近人类活动密集区处于中等至较高重金属污染状态。     

南充市郊蔬菜基地土壤重金属污染状况调查与评价

分析了南充市郊蔬菜地土壤中的pH、有机质、N、P、K及重金属（Pb、Cd、As、Ag、Cr）含量,并用单项污染指数和综合污染指数评价方法,对土壤重金属污染状况进行评价。结果表明该地区多数蔬菜地未受到污染,属于清洁安全,但是仍然有一部分地区受到污染,从综合污染指数看,部分超过了3级水平,处于轻污染。     

Changes in concentrations of fluoroquinolones and of ciprofloxacin-resistant Enterobacteriaceae in chicken feces and manure stored in a heap

This study evaluated the impact of storing chicken manure on the degradation of enrofloxacin (ENR) and ciprofloxacin (CIP), and on the survival of CIP-resistant Enterobacteriaceae. At 24 d of age, half of 8900 chickens received ENR for 5 d. After the animals departed, their manure was stored in two heaps for 63 d. Enterobacteriaceae were cultured on media containing 0 to 32 mg L?1 of CIP. A total of 320 isolates were fingerprinted using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) to evaluate community structure. Initial concentrations of ENR and CIP in the heap were 22 and 1.8 mg kg?1, respectively. Seventy-three percent of the two fluoroquinolones were eliminated during storage. The administration of ENR led to a 5.1 log??? decrease in Enterobacteriaceae concentrations and emergence of CIP-resistant bacteria, which became dominant in the feces. concentrations decreased 1.2 to 2.3 log??? 2 d after the heaps were made and continued to decline during storage. No resistant were found by Day 63. The highest CIP minimum inhibitory concentration (MIC) values observed among isolates of and of both and sp. were 128 and 4 mg L?1, respectively. The dominant ERIC-PCR profiles changed over time. There was no relationship between genotype and resistance-isolated strains to CIP. Storing chicken manure in heaps appeared to be an effective way of limiting the entrance of CIP-resistant E. coli into the environment but did not prevent the dissemination of fluoroquinolones after land spreading.     

Flocculant in wastewater affects dynamics of inorganic N and accelerates removal of phenanthrene and anthracene in soil

Recycling of municipal wastewater requires treatment with flocculants, such as polyacrylamide. It is unknown how polyacrylamide in sludge affects removal of polycyclic aromatic hydrocarbons (PAH) from soil. An alkaline-saline soil and an agricultural soil were contaminated with phenanthrene and anthracene. Sludge with or without polyacrylamide was added while emission of CO₂ and concentrations of NH₄⁺, NO₃⁻, NO₂⁻, phenanthrene and anthracene were monitored in an aerobic incubation experiment. Polyacrylamide in the sludge had no effect on the production of CO₂, but it reduced the concentration of NH₄⁺, increased the concentration of NO₃⁻ in the Acolman soil and NO₂⁻ in the Texcoco soil, and increased N mineralization compared to the soil amended with sludge without polyacrylamide. After 112 d, polyacrylamide accelerated the removal of anthracene from both soils and that of phenanthrene in the Acolman soil. It was found that polyacrylamide accelerated removal of phenanthrene and anthracene from soil.     

燃煤电厂SCR烟气脱硝系统优化流场分析

以合山电厂600MW燃煤锅炉SCR脱硝反应系统的优化流场分析为例,研究数值模拟和冷态试验在电厂SCR系统流场分析中的应用。结果表明,数值模拟和冷态试验结果较为吻合,验证了数模优化方案的可行性。其中,速度场、浓度场和压降都满足设计要求,烟气经整流格栅优化后可以垂直进入催化剂层,模型中无明显积灰。     

“土壤污染防治面临两大挑战”——专访中国科学院南京分院院长周健民

<正>2016年,国务院印发了《土壤污染防治行动计划》(以下简称"土十条")。这是我国土壤环境管理历史上里程碑式的文件。在中国科学院南京分院院长周健民看来,土壤污染具有长期性、复杂性和潜伏性的特点,所以其修复过程比大气和水污染治理所需技术更为综合、时间更为漫长。"土壤污染治理面临两大挑战:一是土壤污染的底数不清,我们还没建立起详细而完整的地块污染数据库;     

Energetic valorization of SRF in dedicated plants and cement kilns and guidelines for application in Greece and Cyprus

A debate is still open on issues of waste to energy methodologies aiming to answer to questions of particular relevance, such as whether the concept of SRF/RDF production can be applied directly to MSW through the Mechanical–Biological Treatment (MBT) process, when selective collection acts as a virtual pre-treatment of the same, or if the use of SRF/RDF as alternative fuel in cement kilns is the most sustainable solution. In this study, two scenarios were analyzed and compared: (a) the use of SRF in a new dedicated thermal plant for electricity production and (b) the use of SRF as an alternative fuel in an existing cement plant. The comparative assessment was based on principles of Sustainable Waste Management embracing technical and cost issues, environmental protection, industrial ecology and symbiosis. The application of SWOT analysis showed that the use of SRF in cement kilns is more sustainable compared to its use in a new dedicated plant for electricity production.     

Retention and runoff losses of atrazine and metribuzin in soil

Minimizing herbicide runoff and mobility in the soil and thus potential contamination of water resources is a national concern. Metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one] and atrazine [2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine] dynamics in surface soils and in runoff waters were studied on six 0.2-ha sugarcane (Saccharum spp.) plots of a Commerce silt loam (fine-silty, mixed, superactive, nonacid, thermic Fluvaquentic Endoaquept) during three growing seasons under different best management practices. Metribuzin was applied in the spring as a postemergence herbicide and atrazine was applied following winter harvest. Both herbicides were applied on top of the sugarcane rows as 0.6- or 0.9-m band width application, or broadcast application, where the entire area was treated. Maximum effluent concentrations were measured from the broadcast treatment and ranged from 600 to 1100 microg L(-1) for atrazine and 250 to 450 microg L(-1) for metribuzin. Atrazine runoff losses were highest for the broadcast treatment (2.8-11% of that applied) and lowest for the 0.6-m band treatment (1.9-7.6%), with a similar trend for metribuzin losses. Measured extractable herbicides from the surface soil exhibited a sharp decrease with time and were well described with a simple first-order decay model. For atrazine, estimates for the decay rate (lambda) were higher than for metribuzin. Results based on laboratory adsorption-desorption (kinetic-batch) measurements were consistent with field observations. The distribution coefficients (Kd) for atrazine exhibited stronger retention over time in comparison with metribuzin on the Commerce soil. Moreover, discrepancies between adsorption isotherm and desorption indicated slower release and that hysteresis was more pronounced for atrazine compared with metribuzin.     

迎评促建期间大学生思想政治工作的开展与思考

搞好大学生思想政治工作对促进学校的建设工作意义重大.针对当前我院迎评促建工作中的学生思想上存在的误区,应进一步加强宣传、加强思想政治工作队伍建设以及不断总结过去和创新现在,根据当前迎评促建工作的实际,采取一定措施.     

噻呋酰胺在马铃薯和土壤中检测方法及残留动态研究

建立了马铃薯果实、植株和土壤样品中噻呋酰胺的分析方法,并测定了噻呋酰胺在马铃薯田中的残留消解动态及最终残留量。样品采用丙酮提取,二氯甲烷萃取,气相色谱-电子捕获检测器（GC-ECD）检测。当样品中添加的质量分数为0.001～0.05 mg·kg^-1时,平均添加回收率为85.76%～93.53%,相对标准偏差（RSD）为1.44%～7.33%,噻呋酰胺的最低检出质量浓度（LOQ）为0.001 mg·kg^-1。2009—2010年在天津和南京两地的田间残留试验结果表明：噻呋酰胺在马铃薯植株和土壤中消解较快,半衰期分别为6.08～6.30 d和4.92～7.07 d,施药后21 d的消解率均在91%以上;240 g·L^-1噻呋酰胺悬浮剂按推荐剂量480 g·hm^-2和1.5倍推荐剂量720 g·hm^-2兑水喷雾1次,在马铃薯收获期时噻呋酰胺在马铃薯果实和土壤中的最终残留量分别为质量浓度0.076 2～0.649 6 mg·kg^-1和0.020 7～0.305 0 mg·kg^-1。根据大田试验结果,建议噻呋酰胺在马铃薯中的最大残留限量标准为1.0 mg·kg^-1。     

中国资源节约型、环境友好型社会建设的胁迫与选择

中国是资源大国,同时又是人口大国.中国经济社会发展正在经历从资源过度消耗、牺牲环境促进经济规模的扩张到人与自然和谐,最终实现人类社会经济的可持续发展的过程.在分析中国资源节约型、环境友好型社会选择背景的基础上,阐明节约型与友好型社会的本质与内涵,提出了资源节约型、环境友好型社会建设的保障措施.     

Recent Changes in Stream Flashiness and Flooding,and Effects of Flood Management in North Carolina and Virginia

The southeastern United States has undergone anthropogenic changes in landscape structure, with the potential to increase (e.g., urbanization) and decrease (e.g., reservoir construction) stream flashiness and flooding. Assessment of the outcome of such change can provide insight into the efficacy of current strategies and policies to manage water resources. We (1) examined trends in precipitation, floods, and stream flashiness and (2) assessed the relative influence of land cover and flow‐regulating features (e.g., best management practices and artificial water bodies) on stream flashiness from 1991 to 2013. We found mean annual precipitation decreased, which coincided with decreasing trends in floods. In contrast, stream flashiness, overall, showed an increasing trend during the period of study. However, upon closer examination, 20 watersheds showed stable stream flashiness, whereas 5 increased and 6 decreased in flashiness. Urban watersheds were among those that increased or decreased in flashiness. Watersheds that increased in stream flashiness gained more urban cover, lost more forested cover and had fewer best management practices installed than urban watersheds that decreased in stream flashiness. We found best management practices are more effective than artificial water bodies in regulating flashy floods. Flashiness index is a valuable and straightforward metric to characterize changes in streamflow and help to assess the efficacy of management interventions.