三八河河口潮滩有机碳、油类、硫化物及微生物分布特征

为了评价烟台市牟平区三八河河口潮滩中主要污染物的分布及土著微生物的修复潜力,研究了潮滩沉积物中w(TOC),w(油类),w(硫化物)和微生物的水平及垂直分布规律. 利用单因子污染指数法对污染状况进行了分析. 结果表明:各因子污染指数由大到小为有机碳(TOC)>硫化物>油类,河口区域w(TOC),w(油类)和w(硫化物)明显高于对照点,越靠近河口表层(0～≤20 cm)沉积物污染越重,说明潮滩污染主要由河流排污引起. 垂直深度上污染物主要集中在亚表层(5～≤20 cm),0～≤50 cm深度范围内w(TOC),w(油类)和w(硫化物)随深度的增加呈先增大后减小的趋势. 微生物分布规律显示,外源有机物的输入可提高沉积物中异养菌总数和呼吸强度,潮滩微生物可通过呼吸过程实现有机碳的矿化和输出,具有一定的修复潜力.      

水相中有机化学品和卤素自由基反应速率常数的定量结构-活性关系模型

卤素自由基尤其是氯自由基在污水中难降解污染物的降解以及表层海水中环境微污染物的降解过程中发挥重要作用,能够影响污染物的环境持久性与毒性风险.在污水及表层海水中存在着多种多样的有机污染物,单纯依靠实验手段测定它们和氯自由基的反应速率常数费时费力并且成本较高.因此本研究通过发展氯自由基与有机污染物的反应速率常数的QSAR模...     

新常态下如何实现环境保护的纳什均衡

从自然资源和生态环境的公共性出发,认为以经济建设为中心的政策选择,促成了以淡视生态环境为前提的均衡策略,让经济发展与环境保护之间形成"坏"的纳什均衡,而新常态能够为经济发展和环境保护之间达成好的纳什均衡提供了改革保障、法制保障和经济保障,因此,新常态下的生态文明建设能够解套环境保护的"囚徒困境",最重要的任务是借助政府这一外力制定新的"游戏规则",以打破原有的"纳什均衡",通过建立健全环境成本内部化的政策措施和生态补偿机制、改革政绩考核机制实现对绿色发展的激励等措施,推进经济发展与环境保护之间达成理想的"纳什均衡"。     

基于淹水特征的分时段湿地生态系统管理——以南洞庭湖万子湖为例

利用2013年遥感影像和地形图制作地势图,将万子湖湿地洲滩分为27 m以下、27~28、28~29、29~30、30 m以上共5级地势阶梯。利用1983~2013年万子湖逐日平均水位数据分析不同地势阶梯洲滩在春汛期、洪水期、退水期、枯水期等4个时段的淹水特征,结合生物特性和人为干扰分析,确定万子湖湿地生态系统管理的边界范围和策略。研究表明:4个时段中的生态系统管理边界分别为29、31、29、28 m地势阶梯分界线,3个重点时段和管理区域为:春汛期,管理目标是产卵亲鱼保护,28 m以下洲滩是重点管理区域;退水期,管理目标是保障鱼类洄游,28 m以下洲滩和湖槽洄游通道是重点管理区域;枯水期,管理目标是洲滩上鱼类产卵场、幼鱼索饵场和越冬候鸟栖息地的恢复与保护,28 m以下洲滩是重点管理区域。而生态系统管理重点则是去除过度人为干扰(包括洲滩过度开发、过度捕捞),恢复湿地生态系统整体性功能,应坚决停止重点区域内滩涂水面的养殖承包、引淤抬洲、洲滩植树等系列干扰性活动。     

Interactions between metal ions and the biopolymer in activated sludge: quantification and effects of system pH value

The quantification and effects of system pH value on the interactions between Pb(II) and the biopolymer in activated sludge were investigated. The biopolymer had two protein-like fluorescence peaks (Ex/Em = 280 nm/326–338 nm for peak A; Ex/Em = 220–230 nm/324–338 nm for peak B). The fluorescence intensities of peak B were higher than those of peak A. The fluorophores of both peaks could be largely quenched by Pb(II), and the quencher dose for peak B was about half of that for peak A. The modified Stern-Volmer equation well depicted the fluorescence quenching titration. The quenching constant (Ka) values for both peaks decreased with rising system pH value, and then sharply decreased under alkaline conditions. It could be attributed to that the alkaline conditions caused the reduction of available Pb(II) due to the occurrence of Pb(OH)₂ sediments. The Ka values of peak B were bigger than those for peak A at the same system pH values. Accordingly, the aromatic proteins (peak B) played a key role in the interactions between metal ions and the biopolymer.

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不同来源污泥接种餐厨垃圾厌氧发酵产氢效果研究

在相同接种配比(接种污泥占餐厨垃圾的质量分数为30%)条件下,研究了4种不同来源污泥(压滤污泥、厌氧污泥、曝气污泥和河底淤泥)添加或不添加缓冲剂时对餐厨垃圾厌氧发酵产氢效果的影响.结果发现,在不添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>河底淤泥>压滤污泥>曝气污泥,接种厌氧污泥的餐厨垃圾平均产氢量最高,达10.11mL(以每克挥发性固体(VS)计,下同);而添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>曝气污泥>压滤污泥>河底淤泥,接种厌氧污泥的餐厨垃圾平均产氢量也最高,为33.72 mL,且体系pH得以缓冲.     

废润滑油絮凝脱色试验研究

废润滑油的回收再生利用不仅可以节约石油资源,而且是防治废润滑油污染、保护环境的主要措施.针对有污染的传统酸-白土废润滑油再生工艺,提出了以絮凝为主的无污染再生新技术,重点考察了影响废润滑油脱色再生效率的各种因素.结果表明,在絮凝剂用量为1.2%(体积分数)、搅拌时间为5 min、反应温度为75℃、沉降温度为80℃、沉降时间为2.0 h的条件下,废润滑油絮凝脱色效果最佳.废润滑油经过絮凝脱色和白土精制后理化指标得到了较大改善,基本接近该级别新油SC40的标准.     

钼矿区土壤中重金属污染状况的分析与评价

对葫芦岛钼矿区土壤重金属污染的情况进行了详细研究。选择土壤样本80个,采用HNO3-HF-HClO4混酸对土壤样品进行处理,运用等离子体发射光谱仪(ICP-OES)测定土壤样品中Pb、As、Hg、Cr、Cd、Zn、Cu、Ni、Mo的含量,全面系统地评价土壤重金属污染现状。结果表明,该矿区土壤重金属As、Cd和Hg污染较为严重,平均含量分别达154.13mg/kg,74.92mg/kg和3.06mg/kg。不同片区间存在明显差别,污染强度以矿山山沿污染最高,其次是运输区、选矿厂及矿区附近山地,内梅罗综合指数分别为78.34、74.34、71.42、68.55。     

典型喀斯特地区土壤-作物系统镉的富集特征与污染评价

为了研究喀斯特地区Cd在表层土壤和农作物中的富集特征及影响因素,为土地安全利用提供理论依据,选择在重庆市黔江区中部采集表层土壤样品360件、深层土壤样品7件、85件水稻样品和73件玉米样品(配套采集根系土样),分析了土壤及农作物中Cd的含量、土壤中TFe2O3、Mn、有机质(Corg)、Se等含量和土壤pH.基于地统计...     

Environmental pollution by persistent toxic substances and health risk in an industrial area of China

Soil is an important environmental medium that is closely associated with humans and their health. Despite this, very few studies have measured toxicants in soils, and associated them with health risks in humans. An assessment of health effects from exposure to contaminants in soils surrounding industrial areas of chemical production and storage is important. This article aims at determining pollution characteristics of persistent toxic substances (PTS) in an industrial area in China to unravel the relationship between soil pollution by PTS and human health. One hundred and five soil samples were collected and 742 questionnaires were handed out to residents living in and around an industrial area around Bohai Bay, Tianjin in Northern China. Concentrations of organochlorine pesticides and polycyclic aromatic hydrocarbons (PAHs) were determined in soil. Mann-Whitney U and binary multivariate nonconditional logistic regression models were employed to analyze the relationship between health indicators of local residents and contaminant levels. Odds ratio (OR) and a 95% confidence interval (CI) for health incidences were also calculated. The average concentrations of DDT (73.9 ng/g), HCH (654 ng/g) and PAHs (1225 ng/g) were relatively high in the industrial area. Residents living in the chemical industry parks were exposed to a higher levels of PTS than those living outside the chemical industry parks. This exposure was associated with a higher risk of breast cancer (OR 1.87, 95% CI 0.12–30.06), stomach cancer (OR 1.87, 95% CI 0.26– 13.41), dermatitis (OR 1.72, 95% CI 1.05–2.80), gastroenteritis (OR 1.59, 95% CI 0.94–2.68), and pneumonia (OR 1.05, 95% CI 0.58–1.89).