雨水管道沉积物中典型无机氮的干期粒径分布

以南京江北新区分流制雨水管道沉积物为研究对象,考察不同粒径沉积物中铵态氮（NH₃-N）和硝态氮（NO₃^--N）干期分布特征,分析其随干期长度的变化关系,并探讨沉积物理化性质及微生物菌群结构对NH₃-N和NO₃^--N干期分布的影响.结果表明：粒径≤0.075mm的沉积物中NH₃-N占比最高（交通区30.8%,商业区36.7%）;交通区粒径≤0.075mm的沉积物中NO₃^--N占比最高（33.0%）,而商业区粒径0.075~0.15mm沉积物中NO₃^--N占比最高（34.4%）;干期长度与交通区0.075~0.15mm粒径段的沉积物中NO₃^--N含量及商业区粒径≥0.3mm的沉积物中NH₃-N含量之间的相关性均最显著;雨水管道沉积物中NH₃-N和NO₃^--N的干期分布与O-H和N-H等官能团、表面极性和亲水性、微观形貌等有一定关联;交通区雨水管道沉积物中Gemmobacter等反硝化优势菌种（相对丰度总和为20.15%）对NO₃^--N干期分布影响更显著.     

Mercury levels in sediments of central Mediterranean Sea: a 150+ year record from box-cores recovered in the Strait of Sicily

To evaluate the degree of anthropogenic mercury pollution, Hg contents have been measured for box-core sediments sampled along three nearshore–offshore transects in the Strait of Sicily and well constrained for their mineralogy, bulk geochemistry and TOC%. Hg values are generally low (from 15 to 70 μg kg⁻¹); however, depth profiles clearly display upcore rising concentrations (up to 202 μg kg⁻¹ near the SE Sicily coast) that are attributed to anthropogenic load. Based on ²¹⁰Pb chronology, these trends are more dramatic across the last 20–30 years. Geogenic influence is thought to explain some anomalies related to volcanic emission and geothermal activity. Combined effects due to eastward flowing of the Modified Atlantic Water (MAW) and sea bottom morphology drove major anthropogenic accumulation.     

Concentration and fate of persistent organochlorine pesticides in estuarine sediments using headspace solid-phase microextraction

The concentration and fate of persistent organochlorine pesticides (OCPs) in estuarine surface sediments in Erh-jen and Lan-yang rivers, Taiwan were investigated using headspace solid-phase microextraction (HSSPME) method to evaluate the possible pollution potential and guideline for OCP concentrations in Taiwan. The HSSPME method exhibits a good analytical performance with low detection limits for OCP determination in sediment. In addition, results obtained using the developed HSSPME method were in good agreement with those obtained using Soxhlet extraction in a certified sample. The developed analytical method was further applied to the determination of concentrations of OCP residues in surface sediments from the estuaries of the selected rivers in Taiwan. A total of 20 surface sediments from each river was collected from 10 sampling stations. The total OCP concentrations in sediments from Erh-jen River ranged from 0.17 to 5.04 ng/g-dw with the mean values of 0.25–1.24 ng/g-dw for HCHs, 0.10–0.89 ng/g-dw for cyclodienes and 0.16–0.64 ng/g-dw for DDTs. The concentrations of OCPs in sediments from Lan-yang River were in the range 0.37–0.9 ng/g-dw with an average of lower than 0.5 ng/g-dw. HCHs and DDTs were abundant in the estuarine sediments from the selected rivers. Results obtained in this study show that the origin of OCPs in the surface sediments from Erh-jen River is a combination of erosion of the weathered soils and long-range atmospheric transport, while the OCP concentrations found in Lan-yang River could be regarded as the background levels of OCPs in Taiwan.     

Heavy Metal Contamination and Distribution in the Urban Environment of Guangzhou, SE China

Ever-increasing heavy metal accumulation in the urban environment of Guangzhou, the largest light industrial production base and one of the most rapidly developing cities in China, poses a serious threat to environment as well as to human health in the region. As a sink or source, urban deposits are good indicators of the level and extent of heavy metal accumulation in the surface environment. The aim of this preliminary study was to examine the distribution of heavy metal contamination in the urban environment of Guangzhou. It was based on a systematic sampling of road dusts and corresponding gully sediments along major roads running mainly through commercial and residential to industrial districts of the city. In addition to road dusts and gully sediments, ceiling dusts from the Pearl River Tunnel were also collected to characterize anthropogenic emissions dominated by traffic-related activities. In general, the level of Cd, Cu, Pb and Zn contaminations were more severe on the industrialized side of Guangzhou than on the western side where heavy traffic and industrial activities were limited. The primary determinants of the level of heavy metal contamination and the distribution of this contamination in the urban environment of Guangzhou were the site-specific conditions of its urban setting, particularly the types of industries, the nature of the traffic flow, sample residence times and variations in grain size of the particulate contaminants. This study highlights the complexity of the urban system and indicates that in just such a system individual urban components should be interlinked to assess the long-term environmental and health effects of heavy metal contamination. Among the heavy metals tested – Cd, Cu, Pb and Zn – the level of Zn contamination was the most severe and widespread, and thus requires immediate attention.     

杭州城区河道底泥重金属污染及潜在生态风险评价

对杭州城区34条河道45个点位河道底泥进行采样,分析了pH及汞、砷、铅、铬、镉、铜、锌、镍等重金属含量,并进行污染及潜在生态风险评价。结果表明,监测点位的底泥为中性偏碱性,重金属含量分布不均,且范围波动很大,部分河道底泥重金属中汞、铅、镉、铬、锌、镍等有不同程度的超标,少数河道镉、铬、锌污染严重;按《农用污泥中污染物控...     

2006年春季长江口砷形态分析及其生物有效性

于2006年春季在长江河口开展野外调查.采集水和表层沉积物样品,并进行总砷、砷形态分析和生物有效性评估.将过滤水样用于测定溶解态砷含量,而未过滤水样经酸消解后用于测定总砷含量,两者之差则为颗粒态砷含量.结果表明.长江口青草沙水源地各层水体中总砷含量为0.88-1.35ug·L-1(涨憩),2.37-3.35ug·L-1(落憩).溶解态和颗粒态砷含量均随潮汐变化明显,各形态砷含量在落憩时均高于涨憩时,颗粒态砷所占总砷的比例也是落憩时明显高于涨憩时.以0.3 mol·L-1磷酸溶液为萃取剂.在微波辅助下可以有效地将沉积物中砷酸盐[As(V)]、亚砷酸盐[As(Ⅲ)]、一甲基胂酸盐(MMA)和二甲基胂酸盐(DMA)提取出来,然后利用高效液相色谱一氢化物发生.原子吸收光谱(HPLC-HG-AAS)联用技术进行检测.结果表明,长江口表层沉积物中总砷含量为6.3-30.7 mg·kg-1,主要为无机砷形态,在江心沙洲及离岸沉积物中且以砷酸盐为主.而在近岸沉积物中以亚砷酸盐为主;利用醋酸纤维素/氧化铁复合膜方法(FeO/CAM)所得沉积物中有嫂砷含量占总砷含量0.6%-3.9%,平均约为2.1%.有效砷含量与总砷含量没有显著相关性,与亚砷酸盐含量呈显著正相关性,与砷酸盐含量呈显著负相关性.结果还表明,长江口南支沉积物中的砷形态分布特征及其生物有效性受城市支流输入和排污活动影响显著.     

河流沉积物重金属污染质量控制基准的研究 Ⅱ.相平衡分配方法(EqP)

以重金属污染严重的江西乐安江表层沉积物为对象，利用热力学相平衡分配法（ＥｑＰ）和相关基础数据库，研究探讨了该流域沉积物中重金属污染的数值型质量控制基准（ＳＱＣ）。结果表明，铜矿采矿活动导致某些江段沉积物中铜实际污染程度远高于相应的ＳＱＣ水平。另外，由于沿江中、小工矿企业废水的随意排放，同样造成附近沉积物中铅、锌、铬等重金属含量不同程度地超出各自的基准数值。此ＳＱＣ的建立为制订该流域沉积物质量管理标     

区域水化学条件对淮南采煤沉陷区水域沉积物磷吸附特征的影响研究

在淮南潘谢采煤沉陷区水域的潘集(PJ)、顾桥(GQ)、谢桥(XQ)各选一研究站点,研究区域水化学条件下溶液离子组分对表层沉积物磷(P)吸附特征的影响.等温吸附实验分别在纯水、NaCl、CaCl2、NaHCO3和NaHCO3+CaCl2共5组环境溶液中进行,其中前4组设置为探讨各组分对P吸附的单独作用,最后1组代表各组分的综合作用.结果表明,环境溶液设置对P的吸附特征有重要影响,Ca2+能显著增强沉积物对P的吸附潜能,而弱碱性环境(NaHCO3组)则不利于沉积物对P的吸附,实际水化学条件下的作用则表现为二者的综合,但Ca2+增强作用要显著大于碳酸盐弱碱性缓冲体系的弱化作用.3个站点沉积物P的零吸附平衡浓度(EPC0)的均值分别为0.059、0.032和0.040 mg·L-1,总体上有向水体释磷的趋势,PJ站点释放潜能要高于GQ和XQ站点,与研究水域营养水平密切相关.由于特殊的沉积环境,研究水域P释放潜能比富营养化程度较高的湖泊要弱,接近于营养水平较低的水体.     

典型电器工业区河涌沉积物中有机污染物特征分析

为评估制造业对纳污水体有机物的污染影响,了解污染河道中有机物的种类、含量及赋存特性,采用极性和非极性逐步分离的方法对广东佛山市顺德区容桂街道内河涌沉积物中的有机物进行了综合的物理图谱解析研究.结果表明,污染沉积物中共检出包括烷烃类、烯烃类、多环芳烃、苯系物、杂环类、邻苯二甲酸酯类、醛酮、极性化合物、含硅物质以及烷酸酯类等10大类有机污染物共171种.按检出污染物种类的数量分析,烷烃类>极性化合物>多环芳烃>醛酮类>杂环>苯系物、邻苯二甲酸酯类>烷酸酯类>含硅物质>烯烃.按照有机物相对丰度分析,烷烃类>极性化合物>烷酸酯类>烯烃类>多环芳烃>邻苯二甲酸酯类>含硅物质>醛酮>杂环类>苯系物.在相对含量最高的烷烃类有机污染物中,十九烷在同类物质中占比高达14.83%.毒害性持久性有机污染物多环芳烃的总有机物占比为2.33%,检测中还发现大量有机醇、酚等和涂料工业,邻苯二甲酸酯类等塑料工业以及和电子工业产业相关的有机硅类等物质.和同类研究相比,该区域检出51种、占总有机物55.5%丰度的烷烃类物质种类更丰富,含量更高.本研究对制造业纳污河涌沉积物的有机污染物分析研究,为同质污染河涌的污染治理提供参考.     

黄河三角洲滨海湿地表层沉积物重金属区域分布及生态风险评价

对黄河三角洲滨海湿地表层沉积物重金属含量变化区域分布特征进行了分析,探讨了沉积环境对重金属分布的影响,采用Hakanson潜在生态风险指数法综合评价了黄河三角洲滨海湿地沉积物中重金属污染状况和潜在风险程度.结果表明,黄河三角洲滨海湿地表层沉积物Hg、Cu、Pb、Zn、Cd和Cr的均值分别为0.034、18.733、19.393、65.317、0.235和62.940μg.g-1.黄河三角洲滨海湿地重金属分布存在区域差异,现行河口区重金属含量最高,鲁北古代黄河三角洲区重金属含量次之,废弃河口区为最低.重金属区域分布受水动力条件的影响显著,黏土含量对重金属的富集和分布也起到一定控制作用.黄河三角洲滨海湿地表层沉积物质量状况良好,综合污染指数为0.10～4.14,处于低污染状态,Cr是主要污染因子,均值为0.63.6种污染物的污染程度由高到低的顺序为Cr>Cu>Zn>Cd>Pb>Hg.综合潜在生态风险指数介于0.46～51.88之间,具有较低的潜在生态风险.6种污染物潜在生态风险参数由大到小顺序为Cd>Hg>Cu>Cr>Pb>Zn,Cd是黄河三角洲的主要潜在生态风险因子.