镧对UV-B胁迫下大豆幼苗类黄酮含量与抗氧化能力影响

为进一步认识La(Ⅲ)提高类黄酮含量及减轻UV-B辐射伤害植物机制,以大豆幼苗为材料,采用水培实验的方法研究了La(Ⅲ)对UV-B辐射胁迫下大豆幼苗类黄酮抗氧化能力的动态影响.结果表明, UV-B辐射(T1:0.15W·m-2和T2:0.45W·m-2)胁迫下,大豆幼苗类黄酮含量在胁迫期和恢复期均先升后降,质膜透性、MDA含量先升(1～5d)后降(6～11d),类黄酮对O·-2和·OH的清除率与其含量变化趋势近同.各处理组类黄酮含量La(Ⅲ) UV-B>UV-B>La(Ⅲ)>CK, La(Ⅲ) T1>La(Ⅲ) T2;质膜透性、MDA含量UV-B>La(Ⅲ) UV-B>CK>La(Ⅲ), La(Ⅲ) T2>La(Ⅲ) T1;类黄酮对O-2和·OH清除率La(Ⅲ) UV-B>UV-B>La(Ⅲ)>CK, La(Ⅲ) T1, La(Ⅲ) T2,表明La(Ⅲ)对类黄酮的调控作用,提高了清除活性氧自由基的运行效率,降低了MDA浓度,维持了质膜正常透性,且对低剂量(T1)的防护效果优于高剂量(T2),进而在防御系统层面实现了La(Ⅲ)对UV-B辐射伤害大豆幼苗的防护效应.     

实时定量RT-PCR方法检测雌二醇诱导原代培养青鳉鱼肝细胞的基因表达

利用原代培养的雄性青鳉鱼肝细胞进行了相同雌二醇(E2)浓度(100 nmol·L-1)下的不同时间(2、4、6、8d)和相同暴露时间(4d)下的不同浓度(1、10、100、1000、10000 nmol·L-1)的雌二醇(E2)实验,采用实时定量RT-PCR方法对青鳉鱼VTG-Ⅰ、VTG-Ⅱ、CHG-H、CHG-L和ERα的基因表达进行了研究,结果表明,VTG-Ⅰ、VTG-Ⅱ、CHG-H、CHG-L和ERα的基因表达与E2的暴露浓度呈现很好的剂量-效应关系,且1nmol·L-1E2暴露就能显著诱导肝细胞内VTG-Ⅰ、VTG-Ⅱ、CHG-H、CHG-L和ERα的基因表达.作为生物监测雌激素活性的in vitro方法,实时定量RT-PCR的灵敏度高于其它已经发表的方法.因此,实时定量RT-PCB方法与原代培养青鳉鱼肝细胞相结合的方法在环境雌激素效应的评价上具有很大地应用潜力.     

固体废物浸出毒性浸出方法标准研究

对国内外浸出方法标准体系、研究方向、应用目标、方法的特点和缺陷进行了系统总结,介绍了《固体废物 浸出毒性浸出方法 硫酸硝酸法》(HJ/T299—2007)和《固体废物 浸出毒性浸出方法 醋酸缓冲溶液法》(HJ/T300—2007)的模拟场景、方法学探讨和实验研究结果. 目前,HJ/T299—2007已经成为我国危险废物浸出毒性鉴别的指定标准方法,而HJ/T300—2007也被用于特定危险废物和一般工业废物进入生活垃圾填埋场的入场检验. 新制定的浸出方法标准的环境保护目标和模拟场景假设明确,实验参数由理论计算和系统的实验获得,具有较充分的方法学依据. 尽管如此,对于该标准的客观、全面的评估还需要经过长期的执行过程才能获得,新的浸出方法标准只是在现有研究基础上的阶段性成果,还要随着环境管理的需要和细化以及研究的不断深入而加以补充和修改.      

我国湖泊富营养化防治与控制策略研究进展

随着全球人口的不断增加,工业化、城市化以及农业现代化的快速推进,湖泊富营养化问题已日益成为全球性的水环境污染问题。近年来,我国经济发展提速,资源利用强度加大,导致湖泊氮、磷营养盐严重富集,某些湖泊生态系统结构遭受破坏,功能紊乱,一些区域的湖泊蓝藻水华频繁爆发,湖泊富营养化呈现迅猛发展的趋势,并对区域经济发展与生产、生活用水保障带来挑战。尽管为了防控湖泊富营养化,我国各级政府投入了大量人力与物力,但在一些湖泊富营养化频繁区,一些防治与控制措施还没有收到理想而满意的效果。文章在综述国内外湖泊富营养化防治与控制策略研究的基础上,阐述了我国在富营养化研究方面存在的主要问题,提出了我国湖泊富营养化分区、分类控制的新思路。     

不同生长期的Pseudomonas putida 5-x细胞对工业废水中Cu~(2+)的吸附

研究了不同生长阶段的Cu2 + 吸附细菌Pseudomonasputida 5 x对Cu2 + 的吸附容量 .结果表明在低硫培养基中 ,当P putida 5 x细胞生长刚进入对数生长期时 ,单位细胞对Cu2 + 的吸附溶量最低 .而当生长进入稳定生长期的后期或死亡期的早期时 ,单位细胞对Cu2 + 的吸附量最大 .实验结果还表明 ,高浓度的Cu2 + 对对数期细胞的吸附能力有一定的抑制 ,而对死亡期的细胞影响较小 .早期研究已证明细胞对重金属离子的吸附和细胞表面某些对重金属离子具有亲和性的功能基团 (如某些膜蛋白及羰基化合物 )有关 .利用透视电子显微镜观察了不同生长阶段的细胞表面结构及对铜离子的吸附效果 ,发现生长后期细胞表面吸附有较多的Cu2 + ,这表明生长后期的细胞表面可能含有较多的这类功能基团     

Selected organochlorine pesticides (OCPs) in surface soils from three major states from the northeastern part of India

Eighty-two surface soil samples were collected from forest, grassland, tea estate, wildlife sanctuary, wetland, and roadside areas from the northeastern states of India, viz., Tripura, Manipur, and Assam. Thirteen different organochlorine pesticides (OCPs) were detected from background soils using gas chromatography electron capture detector. Manipur soils were found to be with higher concentration of dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), and endosulfan followed by Tripura and Assam. The spearman correlation coefficient shows significant correlation between HCHs, DDTs, and endosulfan isomers (r ²?>?0.5 and p?<?0.05). Additionally, α-HCH, δ-HCH, o,p′-DDE, and endosulfan-sulfate shows good correlation with total organic carbon in soil (r ²?=?0.5, p?=?0.05), indicating that the soil organic matter could enhance adsorption of these compounds, also demonstrating that the present OCPs in the background soil were from similar source. Further principal component analysis evaluates that most of the higher volatile compounds where clustered together in soil. However, after comparing with different states of Indian soil samples, the concentrations of OCPs in the present study areas are much lower and comparable with background soil across the globe.     

臭氧激光雷达技术及应用研究进展

差分吸收臭氧激光雷达是完善光化学立体监测体系的重要技术,因其高时空分辨率的廓线探测优势而得以迅速发展,目前已被广泛应用于对流层臭氧浓度的遥感探测。阐述了臭氧激光雷达的原理,归纳总结了雷达系统及关键技术的国内外最新研究进展,梳理了臭氧激光雷达在环境领域的应用现状,并基于我国城市臭氧污染问题现状和管理需求,初步探索设计了臭氧激光雷达监测网络业务应用的整体框架。指出了臭氧激光雷达技术及应用中存在厂家众多但缺乏统一的技术规范和行业标准,数据质量及准确性有待提高,与标准分析方法产生数据的可比性较差等不足之处;提出了核心部件国产化,系统小型化、自动化及商用化,多平台以及与其他监测方式联用等发展趋势。     

Distribution characteristics of polycyclic aromatic hydrocarbons in sediments and biota from the Zha Long Wetland, China

In this paper, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in biota (reed, grass, mussel, fish, and red-crowned crane) and sediments collected from seven locations in the Zha Long Wetland. PAHs were recovered from the sediments and biota by ultrasonic extraction and then analyzed by means of gas chromatography-mass spectrometry. The total PAH concentrations were 244–713 ng/g dw in sediments, 82.8–415 ng/g dw in plants and 207–4,780 ng/g dw in animals. The total sediment PAH concentrations were categorized as lower to moderate contamination compared with other regions of China and the world. In the plant samples, the accumulation abilities of reed roots and stems for PAHs were higher than those of grass roots. In addition, the concentration of individual PAHs in mussel muscles was the highest in all of the animal samples, followed by fish, feeding crane fetuses, and wild crane fetuses. Compositional analysis suggests that the PAHs in the sediments from the Zha Long Wetland were derived from incomplete biomass combustion. Risk assessment shows that the levels of PAHs in sediments are mostly lower than the effects range mean value (effects range mean), whereas only naphthalene in all sample sites was higher than the effects range low value. It is worthwhile to note that benzo(b)fluoranthene, benzo(k)fluoranthene, indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were detected in crane fetal, which have potential carcinogenicity for organisms from the Zha Long Wetland.     

Some technical issues in managing PCBs

Polychlorinated biphenyls (PCBs) were important industrial chemicals featuring high thermal and chemical stability and low flammability. They were widely used as dielectric and thermal fluid in closed electro-technical applications (transformers, capacitors…) and also in numerous dispersive uses, ranking from auto-copying paper to sealant or coatings. During the 1960s, severe environmental consequences started becoming apparent. The stability of PCBs contributed to their persistence in the environment, their lipophilic character to bio-magnification. Fish-eating species seemed threatened in their existence. In Japan and in Taiwan, thousands of people consumed PCB-contaminated oil. The production of PCBs stopped completely during the 1980s. Usage could continue in closed applications only. In this paper, particular attention is given to two issues: the cleaning of PCB electric transformers and the potential impact of PCB-containing building materials. Other contributions will cover the management and treatment of PCB-contaminated soil, sludge or fly ash. The complete survey is being prepared by request of the Knowledge Center for Engineers and Professionals.     

Medium optimization for the production of anti-cyanobacterial substances by Streptomyces sp. HJC-D1 using response surface methodology

Bioremediation using isolated anti-cyanobacterial microorganism has been widely applied in harmful algal blooms (HABs) control. In order to improve the secretion of activated anti-cyanobacterial substances, and lower the cost, a sequential optimization of the culture medium based on statistical design was employed for enhancing the anti-cyanobacterial substances production and chlorophyll a (Chl a) removal by Streptomyces sp. HJC-D1 in the paper. Sucrose and KNO₃ were selected as the most suitable carbon and nitrogen sources based on the one-at-a-time strategy method, and sucrose, KNO₃ and initial pH were found as major factors that affected the anti-cyanobacterial ability of the isolated stain via the Plackett–Burman design. Based on the response surface and canonical analysis, the optimum condition of culture medium was obtained at 22.73 g l^-1 of sucrose, 0.96 g l^-1 of KNO₃, and initial pH 8.82, and the Chl a removal efficiency by strain HJC-D1 increased from 63?±?2 % to 78?±?2 % on the optimum conditions.