长江下游沉积物中重金属污染现状与特征

对长江下游沉积物中的重金属Co、Cr、Cu、Ni、Pb、Zn、Mn、Hg和As进行全量和醋酸提取态(包括水溶态、可交换态和碳酸盐结合态)分析.结果表明,大部分重金属主要来源于地壳元素的自然释放,但Cu、Zn、Hg和As在最近十几年因受到人为排放的影响质量比有所增加.长江江苏段的重金属质量比普遍高于入海口上海段;位于悬浮物易沉降地区的靖江重金属质量比明显偏高.Cu和Zn总体质量比较高,且醋酸提取态所占比例较大,对长江下游存在潜在的生态风险.     

Perfluorooctanoic acid and perfluorooctane sulfonate in the sediment of the Roter Main river, Bayreuth, Germany

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are widely distributed in aquatic ecosystems. Their sources are known but few studies about their accumulation potential in river sediments exist. The aim of this study is to assess the concentrations of PFOA and PFOS in sediments in relation to their levels in river water receiving effluent from a waste water treatment plant (WWTP). PFOS accumulates by a factor of about 40 relative to river water, PFOA only up to threefold. In contrast to previous suggestions, in this case the enrichment on sediment is not correlated to the total organic carbon contents.     

溶解氧对河流底泥中三氮释放的影响

作为内源污染的底泥沉积物中营养物的释放引起了越来越多的关注。通过大型静态土柱模拟实验,研究氮在上覆水和孔隙水中的分布特性和释放特性。在控制氧气条件、底泥有机质含量和粒径大小的条件下,连续观测氨态氮、亚硝态氮和硝态氮的浓度及其垂向分布特性。结果发现：时间分布上,通氧条件明显影响水体底泥中三氮释放与反硝化作用达到平衡的时间;垂向分布上,三期实验的上覆水的无机氮以氨态氮为主,不同的通氧条件下,各柱的孔隙水的三氮浓度比上覆水高,且三氮在沉积物中随深度增加而增加;氨态氮和硝态氮浓度则以孔隙水的为高,随深度增加而增加;低溶解氧水平加快底泥释放氨氮速度和增大释放量。     

PCDD/F and PCB multi-media ambient concentrations, congener patterns and occurrence in a Mediterranean coastal lagoon (Etang de Thau, France)

Ambient concentrations, congener patterns and multi-media distribution of PCDD/Fs and PCBs were determined in air, water, sediment and mussels in a semi-enclosed marine ecosystem (Thau lagoon, France). summation operator2,3,7,8-PCDD/F and summation operator7ICES PCB air concentrations (0.2-1.4 and 31-57pg m(-3), respectively) were typical of rural areas. Concentrations in the water column were very low for PCDD/Fs (163-476fg L(-1)) and low for PCBs (138-708pg L(-1)). PCDD/F and PCB concentrations found in surface sediment (0.15-1.6 and 2.5-33ng g(-1) d.w., respectively) and mussel (13-21pg g(-1) d.w. and 10-39ng g(-1) d.w., respectively) were medium levels. PCDD/F congener patterns observed in air, water particulate phase and sediments were similar suggesting direct coupling among these compartments and atmospheric inputs of PCDD/Fs into the lagoon. Conversely, for the same set of samples, similar patterns were not observed for PCBs in the mentioned compartments.     

福建近岸海域沉积物污染现状与防治措施

根据福建沂近岸海域环境综合调查数据资料，对沉积物质量现状进行了分析评价，结果表明，海域沉积物主要受到金属铅的污染，污染物的主要入海途径是入海河口，并结合海域自然环境和沿岸社会发展的特点，提出相应的防治措施。     

Assessment of heavy metal pollution in wetland soils from the young and old reclaimed regions in the Pearl River Estuary, South China

Soils were sampled in three types of wetlands from the young (A) and old (B) reclaimed regions of the Pearl River Estuary. They were analyzed for total concentrations of heavy metals to investigate their distributions and pollution levels in both regions. Results showed that most heavy metals in ditch and riparian wetlands did not significantly differ from those in reclaimed wetlands in A region, while significantly lower for Cd, Cu, Pb, and Zn in reclaimed wetlands in B region, suggesting higher effects of long-term reclamation. Iron, Cr and Cu were identified as metal pollutants of primary concern and had higher contributions to the total toxic units compared to other metals. Almost all metals exceeded their lowest effect levels and Fe and Cr even exceeded the severe effect levels. Multivariate analysis shows that Fe and Mn are controlled by parent rocks and other metals mainly originate from anthropogenic source.     

Persistent organic pollutants in soils and sediments from James Ross Island, Antarctica

Soil and sediment samples from James Ross Island were analyzed for their PCB, OCP and PAH contents. Soil concentrations ranged between 0.51 and 1.82 ng g(-1) for seven indicator PCB congeners, between 0.49 and 1.34 ng g(-1) for HCH congeners, between 0.51 and 3.68 ng g(-1) for the sum of p,p'-DDT, DDE, and DDD, and between 34.9 and 171 ng g(-1) for the sum of 16 EPA PAHs. Sediment levels from 0.32 to 0.83 ng g(-1) were found for PCBs, from 0.14 to 0.76 ng g(-1) for HCHs, from 0.19 to 1.15 ng g(-1) for DDTs, and from 1.4 to 205 ng g(-1) for PAHs. A prevalence of low-mass PAHs, less chlorinated PCBs, and more volatile chemicals indicates that the long-range atmospheric transport from populated areas of Africa, South America, and Australia is the most probable contamination source for the solid matrices in James Ross Island.     

河湖底泥修复技术的研究进展

本文综述污染底泥的修复技术,探讨其发展状况及存在的问题。指出物理修复见效快,但成本高;化学修复成本较低但易造成二次污染;生物修复投入低,处理量大,但处理效率低,。将这三类技术联合使用,取长补短,具有较广阔的发展前景。     

底质中石油和酚类浸溶试验

研究小东江水闸至斜岭全程１０Ｋｍ河段底质中石油和酚类污染物含量的沿程分布,并对底质进行浸溶试验,结果表明,该河段底质中石油平均含量为２７．５８ｍｇ／ｋｇ,酚类为０．０９８ｍｇ／ｋｇ,石油平均浸出率为３５％,酚类平均浸出率为４９％,在一定的条件下,可能导致水体的二次污染。     

高效液相色谱荧光检测湖泊沉积物间隙水中的微量硫醇

提出了测定天然水中微量低分子质量硫醇的灵敏、可靠方法,即采用7-氟苯并-2-氧-1,3-二唑-4-磺酸铵盐(SBDF)柱前衍生化、逆相高效液相色谱分离和荧光检测技术。文中详细研究了一些洗脱条件,如流动相的组成、pH值和洗脱模式对色谱保留行为的影响,从而获得了最佳的洗脱条件。对于被研究的5种低分子质量硫醇,获得了其浓度在25~250nmol/L范围内的标准曲线和测定限。本方法成功地测定了湖泊沉积物间隙水中的微量硫醇。