Biogeochemical characteristics of settling particulate organic matter in Lake Superior: A seasonal comparison

To assess settling particulate organic matter (POM) seasonality and its availability to the benthic community, settling particulate matter was studied in terms of mass fluxes and main biogeochemical characteristics (including organic carbon (OC), nitrogen, and stable carbon and nitrogen isotopic values) at two Lake Superior offshore sites over the course of a year. Fourier transform infrared spectroscopy (FTIR) and hydrolysis, extraction, and derivatization were used to provide further compositional information. Carbon and nitrogen content, isotopic and wet chemical data, and FTIR spectra show that summer particulate material is mainly autochthonous, with higher proportions of amide and carbohydrate. FTIR shows that spring particulate material contains relatively high proportions of clay minerals, indicating major sources from sediment resuspension and/or spring runoff. Distinct amino acid distributions at the two sites, revealed by principal component analysis (PCA) based on amino acid mol% composition, possibly result from differences in OM sources and the degree of degradation occurring at the two sites. Carbohydrate (PCHO), total hydrolyzable amino acid (THAA) and FTIR data suggest that the nutritional value of bulk POM to benthic heterotrophs should be lower in spring than summer-fall, although both periods exhibited high sinking fluxes of total mass and OC. Due to sediment resuspension events and an oxic water column, organic matter eventually buried in Lake Superior’s sediments has probably experienced extensive alteration due to several cycles through the water column and the bacterially-active sediment-water interface.     

造成香港空气污染的环流聚类特征及对细颗粒物的影响

对2012年5月至2013年5月香港空气污染期间89个污染日的天气环流形势通过模糊聚类的方法进行统计分类,得到大陆冷高压型、入海高压型、东北部热带气旋型和南部热带气旋型4种天气类型。结合细颗粒物(PM_2.5)及其主要组分、气态污染物的日变化特征以及气象参数的相关性分析不同天气型影响下的污染事件在不同季节的污染特征。入海高压型污染事件发生时PM_2.5主成分中二次水溶性无机离子(SIA)的占比明显比其他类型高,尤其是硝酸铵,可能与该天气型造成的高相对湿度、低温度的大气环境有关,进一步研究发现,春季污染事件中二次水溶性无机离子的增长与其前体物的非均相氧化反应有关;秋季硫酸盐的增长与均相氧化反应相关;冬季受季风影响,污染物的跨界输送贡献较大。大陆冷高压天气型造成大范围的下沉运动,静稳大气易导致污染物的积累,在PM_2.5主成分中二次水溶性无机离子和有机物(OM)占比均有增高,秋、冬季二次水溶性无机离子前体物的非均相氧化反应与有机物的光化学氧化反应是造成该污染特征的主要原因之一。在东北部热带气旋型污染事件中有机碳与元素碳质量浓度的比...     

Geochemical study of submicron particulate matter(PM1)in a metropolitan area

Air pollution has become a major problem in urban areas due to increasing industrialization and urbanization.In this study ambient concentrations of PM1 and metal concentrations as well as source contributions were identified and quantified by using Positive Matrix Factorization(PMF)in receptor modeling in the Metropolitan Area of Porto Alegre,Brazil.The PM1 samples were collected on PTFE filters from December 2012 to December 2014 in two sampling sites.Major ion and trace element concentrations were assessed.The average concentrations were 12.8 and 15.2μg/m³ for Canoas and Sapucaia do Sul sites,respectively.Major ion contributions of PM1 were secondary pollutants such as sulfate and nitrate.Trace elements,especially Cu,Pb,Zn,Cd,and Ni also made important contributions which are directly associated with anthropogenic contributions.Our results show significantly higher levels in winter than in summer.Most of the PM1 and the analyzed PM species and elements originated from anthropogenic sources,especially road traffic,combustion processes and industrial activities,which are grouped in 7 major contributing sources.A back-trajectory analysis showed that the long-range transport of pollutants was not relevant in relation to the contribution to PM1 and metal concentrations.This work highlights the importance of urban planning to reduce human health exposure to traffic and industrial emissions,combined with awareness-raising actions for citizens concerning the impact of indoor sources.     

Dynamics of coarse particulate matter in the turbidity maximum zone of the Gironde Estuary

There is a lack of studies devoted to coarse particulate matter (CPM) in estuaries, although this fraction can disturb activities that filter large volumes of water, such as industrial or fishery activities. In the macrotidal and highly-turbid Gironde Estuary, a monthly sampling of CPM was performed in 2011 and 2013 at two stations in the Turbidity Maximum Zone (TMZ) to understand its seasonal, tidal and hydrological dynamics. Regardless of the season and station, low quantities of CPM (few g m⁻³) were observed in comparison with suspended particulate matter (several 10³ g m⁻³). The highest concentrations were consistently recorded in bottom waters and at the upstream station. Whereas there is no clear link between the CPM present in the column water and spring or neap tides, an increase in the CPM size has been identified at the two stations after a flood event, fact potentially critical regarding filtering functioning of estuarine activities.     

西昆仑大红柳滩花岗岩中黑云母地球化学特征及地质意义

西昆仑大红柳滩岩体被认为与伟晶岩锂（铍）矿化密切相关。为约束大红柳滩岩体形成时的物理化学条件、岩石成因类型及源区性质,本文选取大红柳滩岩体作为研究对象,对花岗岩中的黑云母进行背散射观察（BSE）和电子探针分析（EPMA）。研究结果表明：大红柳滩二云母花岗岩与正长花岗岩中的黑云母属铁质黑云母,具有富硅、铝、铁和钾,贫镁、锰、钠和钙的特征;黑云母花岗岩中黑云母为铁质黑云母和镁质黑云母,具有富镁,贫铝、铁的特征。二云母花岗岩和正长花岗岩中黑云母具有高的Al^Ⅵ值（0.7~0.9）,与电气石、石榴子石和白云母等过铝质矿物共存。黑云母花岗岩中的黑云母具有高的MgO含量（9.30%~10.11%）,黑云母与角闪石共存。通过黑云母成分估算二云母花岗岩、正长花岗岩及黑云母花岗岩中黑云母结晶温度分别为661℃~673℃、621℃~669℃、685℃~714℃,固结压力分别为332~404 MPa、356~377 MPa、248~270 MPa,对应侵位深度分别为12.46~14.98 km、13.18~14.38 km、9.18~10.01 km,氧逸度分别为-15.8~-15.0、-16~-15、-14.9~-14.0。综合研究结果表明,大红柳滩地区二云母花岗岩与正长花岗岩为壳源物质重熔的产物,具有典型强过铝质S型花岗岩的特点,而黑云母花岗岩是具有幔源物质混入成因的Ⅰ型花岗岩。本研究成果为大红柳滩岩体不同岩性花岗岩成岩时的物理化学条件、岩石成因类型以及源区性质等方面提供了新资料。

     

洱海沉积物间隙水中溶解有机质的地球化学特性

对洱海沉积物间隙水中溶解有机质(DOM)含量、紫外可见吸收、荧光以及分子量等的垂直分布特征进行了研究。结果表明,DOC含量在沉积物水界面明显富集,随后急剧下降,6cm处达到最小值,随后呈上升趋势。DOC与吸光度值、荧光发射光谱强度之间具有一定的线性相关关系。DOM的E3/E4值范围在1～6之间,绝大多数在1～35之间。表征DOM中腐殖质来源的指标荧光指数值处于148～159之间,说明DOM以陆源输入为主。此外,洱海沉积物间隙水DOM分子量分布呈多峰分布模式,重均分子量(M_w)值在1462～1953Da之间,数均分子量(M_n)值在547～900Da之间,多分散性系数ρ值在202～305之间。随着沉积深度增大,M_w和M_n有略微的增大趋势,但变化不大。沉积物的氧化还原条件、微生物活动以及铁、锰氧化物等在沉积剖面的差异是控制间隙水中DOM各种地球化学特性的主要因素。     

长江悬浮颗粒物中磷的赋存形态

2006年9~10月在长江采集悬浮颗粒物样品,应用改进后的SEDEX法对磷的赋存形态进行了分析.结果表明,自生磷灰石磷是长江悬浮颗粒物中磷的主要赋存形态.涪陵至万州江段,碎屑磷灰石磷的含量较高,弱吸附态磷和有机磷含量较低,磷的赋存形态主要受悬浮颗粒物含量的影响;香溪至葛洲坝下江段,弱吸附态磷和有机磷含量较高,碎屑磷灰石磷含量较低,磷的赋存形态主要受浮游植物生长及泥沙粒径的影响;城陵矶至大通江段,有机磷、碎屑磷灰石磷和铁结合态磷含量较高,弱吸附态磷含量较低,磷的赋存形态主要受泥沙粒径和洞庭湖输入的影响.长江悬浮颗粒物中生物可利用磷占颗粒态磷的45.6%,长江上游水体中生物可利用磷含量较低,下游含量较高.     

Spherical particles as tracers of atmospheric ceramic industry

Castellón province houses the nucleus of ceramics production in Spain (93%). This nucleus, located around in the villages of Castellón, Villarreal, Alcora and Onda, has gone through a special process of industrial expansion. The emissions, most of them of particulate material, can constitute a real environmental problem. A study designed to identify the crystalline and glassy phases in the depositable particulate material has been carried out by SEM/EDX and X-ray diffraction methods. Quartz, calcite, illite, kaolinite, chlorite, and feldspars have been the main crystalline phases identified. The number of spherical morphology particles found in the depositable material is remarkable. The vitreous material found was spherical nodules. Due to the shape, size (1–10 μm), and chemical composition of these particles, they can be excellent tracers of the ceramics industry emissions.The presence of Zn, Ba, or Fe are due to the massive use of these substances as opacifying and pigmentation agents in many ceramics frits and glaze compositions. This fact gives a valuable information that will facilitate the studies guided to obtain important aims such as: toxicology, average size of a particle, formation mechanisms, etc.     

安徽省大气颗粒物污染特征分析

对2016年全年颗粒物监测浓度数据进行统计分析,得到了安徽省颗粒物污染的空间分布、浓度和粒径,以及污染传输特征。结果表明,淮河以北、沿江和江淮之间、长江以南和皖南山区城市颗粒物污染随地理位置不同表现出明显的区域化特征,污染程度由北向南减轻,污染过程明显表现出由北向南逐步扩散传输的规律,污染程度越重,污染深入南方的范围越广,持续时间也越长。冬季污染较重的城市,上午出现明显的高浓度时段,全天变化为"双峰双谷"型。夏、秋季节夜间细颗粒物(PM_2.5)浓度贡献比增加。PM_2.5与PM₁₀(可吸入颗粒物)质量浓度比值冬季最高,春季较低。污染重的城市冬季PM_2.5占比高。     

The effects of surface area, grain size and mineralogy on organic matter sedimentation and preservation across the modern Squamish Delta, British Columbia: the potential role of sediment surface area in the formation of petroleum source rocks

Surface sediment samples were collected from the Squamish River Delta, British Columbia, in order to determine the role of sediment surface area in the preservation of organic matter (OM) in a paralic sedimentary environment. The Squamish Delta is an actively prograding delta, located at the head of Howe Sound.Bulk total organic carbon (TOC) values across the Squamish Delta are low, ranging from 0.1 to 1.0 wt.%. The carbon/total nitrogen ratio (C_org/N) ranges from 6 to 17, which is attributed to changes in OM type and facies variations. The <25-μm fraction has TOC concentrations up to 2.0 wt.%, and a C_org/N ratio that ranges from 14 to 16. The 53–106-μm fraction has higher TOC concentrations and C_org/N ratios relative to the 25–53-μm fraction. The C_org/N ratio ranges from 9 to 18 in the 53–106-μm fraction and 5.5–10.5 in the 25–53-μm fraction. Surface area values for bulk sediments are low (0.5–3.0 m²/g) due to the large proportion of silt size material. Good correlation between surface area and TOC in bulk samples suggests that OM is adsorbed to mineral surfaces. Similar relationships between surface area and TOC were observed in size-fractionated samples. Mineralogy and elemental composition did not correlate with TOC concentration.The relationships between surface area, TOC and total nitrogen (TN) can be linked to the hydrodynamic and sedimentological conditions of the Squamish Delta. As a result, the Squamish Delta is a useful modern analogue for the formation of petroleum source rocks in ancient deltaic environments, where TOC concentrations are often significantly lower than those in source rocks formed in other geological settings.     

北京市大气可吸入颗粒物的化学成分和来源

2007年3月至2008年5月,在北京市成府路东口设立采样点,共采集监测周期为一周的PM2.5(直径小于2.5μm的大气可吸入颗粒物)样品56个,用HR-ICP-MS方法测量了15种元素的含量,并在此基础上应用主因子分析法对PM2.5中这些元素的来源进行探讨。同时,在2008年奥运会和残奥会期间开展了24h时间间隔的密集采样,特别分析了机动车限行期间细颗粒污染物的浓度特征。结果表明,2007年春季至2008年春季期间北京市大气PM2.5平均浓度为72.9μg/m3,超过美国环保局（USEPA）制定的PM2.5年平均浓度限值15μg/m3的近5倍。机动车限行期间北京成府路东口采样点大气PM2.5的平均浓度为40.7μg/m3。通过因子分析方法确定北京PM2.5的3种可能来源：①交通排放、工业排放和燃煤,特征元素为Cu、Zn、As、Sn、Sb、Cd、Pb;②本地扬尘和远源沙尘细颗粒;③可能与成土母岩风化有关的土壤颗粒的再悬浮和/或迁移,其方差贡献率分别为41.2%、31.4%和12.2%。     

北京市大气可吸入颗粒物的化学成分和来源

2007年3月至2008年5月,在北京市成府路东口设立采样点,共采集监测周期为一周的PM2.5(直径小于2.5μm的大气可吸入颗粒物)样品56个,用HR-ICP-MS方法测量了15种元素的含量,并在此基础上应用主因子分析法对PM2.5中这些元素的来源进行探讨。同时,在2008年奥运会和残奥会期间开展了24h时间间隔的密集采样,特别分析了机动车限行期间细颗粒污染物的浓度特征。结果表明,2007年春季至2008年春季期间北京市大气PM2.5平均浓度为72.9μg/m3,超过美国环保局（USEPA）制定的PM2.5年平均浓度限值15μg/m3的近5倍。机动车限行期间北京成府路东口采样点大气PM2.5的平均浓度为40.7μg/m3。通过因子分析方法确定北京PM2.5的3种可能来源：①交通排放、工业排放和燃煤,特征元素为Cu、Zn、As、Sn、Sb、Cd、Pb;②本地扬尘和远源沙尘细颗粒;③可能与成土母岩风化有关的土壤颗粒的再悬浮和/或迁移,其方差贡献率分别为41.2%、31.4%和12.2%。     

三塘湖盆地石头梅地区二叠系芦草沟组有机质富集特征

为了研究三塘湖盆地石头梅地区二叠系芦草沟组有机质富集特征,通过对岩芯详细观察和泥岩系统取样,开展了有机碳、岩石热解、主量元素、微量元素测试分析。结果表明,三塘湖盆地石头梅地区芦草沟组泥岩有机质丰度较大,TOC含量最高12.4%,最大生烃潜量94.41 mg/g,有机质类型以I型和II型为主。有机质成熟度较低,为未熟—低成熟。研究区芦草沟组沉积时期初始古生产力中等,气温较高,水体深度较大,为半深湖—深湖环境,水体主要为停滞水体环境,缺氧还原条件,水体盐度较高,以咸水条件为主。根据地球化学参数,研究区芦草沟组自下而上可以划分出3个层段,对比3个层段中古环境的变化特征,发现同为低水动力深水缺氧还原条件下,适宜的温暖气候条件和适宜的半咸水—咸水盐度条件,以及高初始古生产力有利于有机质富集,从而形成油页岩,同时优选B3层段为油页岩最有利发育层段。     

大气颗粒物中水溶性有机物的理化性质和污染特征研究进展

水溶性有机物(WSOM)是颗粒物的重要组成部分,来源广泛,组成复杂,对大气能见度、全球气候变化以及人体健康均有影响。本文主要综述了近5年国内外有关WSOM的研究成果,主要结论如下:(1)脂肪族化合物是WSOM的主要化学组分,而芳香族化合物含量相对较低;(2)WSOM相对于水溶性无机离子的占比增加时,气溶胶的吸湿增长因子相对较低;(3)不同来源的WSOM,其吸光性能差异较大,生物质燃烧源对WSOM的吸光贡献最大;(4) WSOM主要来自于生物质燃烧和光化学反应的二次生成,其秋、冬季浓度水平明显高于春、夏季,城区和郊区浓度水平均明显高于地区背景点。     

黄海秋季典型站位沉降颗粒物的垂直通量

2002年9月,在海州湾外侧(E1站)、黄海冷水团(E2站)和黄、东海毗邻水域(E3站)分别放置沉积物捕获器采集沉降颗粒物,研究其垂直通量.结果显示,E1、E2和E3站底层颗粒物沉降通量分别为215.44 g/(m2·d)、165.51 g/(m2·d)、873.91 g/(m2·d),POC沉降通量分别为3.15 g/(m2·d)、2.22 g/(m2·d)、10.49 g/(m2·d).生源颗粒物是E1站位次表层POC的主要来源.E3站水体底层的大量悬浮颗粒物主要来自沉积物的再悬浮,再悬浮强烈程度及影响深度均高于E1站.通过模型计算出E2站底层颗粒物再悬浮比率平均(±SD)为95.65(±2.14)%,底表沉积物再悬浮通量占总再悬浮通量的百分比(X值)为89.53%,显示秋季底部平流对黄海冷水团区再悬浮通量影响不大,但这种影响在夏季相对较强.E2站POC净沉降通量为192 mg/(m2·d),生源颗粒物是此站位POC通量的主要贡献者.由于温跃层的长期存在,营养盐贫乏,生物生长受到抑制,导致黄海冷水团区秋季POC通量小于夏季.     

辽宁省典型地区大气颗粒物重金属元素分布特征及对土地质量影响研究

大气颗粒物是大气质量评价中的一个通用的重要指标,近年来,对于大气颗粒物污染这一热点问题开展了大量的研究。文中选取辽宁省沈阳市、锦州市和葫芦岛市等典型地区研究大气颗粒物(TSP、PM10、PM2.5)中Cd等重金属元素的分布特征。结果表明,辽宁省大气可吸入颗粒物中Pb和Zn的含量最高,其次是Cu、Mn、As、Cr、Cd。燃煤、燃油和工业污染源等方面可能是造成这些元素含量较高的主要原因。此外,文中还对大气颗粒物对土地质量的影响研究进行一些有益尝试。研究表明,大气颗粒物中重金属元素含量对土地质量的影响是显而易见的。政府管理部门应该重视对大气颗粒物中重金属元素含量的监控,努力减少其对土地质量的影响。     

大气颗粒物矿物相组成与微观形貌研究进展

矿物颗粒是大气颗粒物的重要组成部分,其物相组成和微观形貌等特征既对人体危害的机理研究具有重要意义,同时蕴藏着颗粒物来源及变化等有用信息。自上个世纪80年代至今,大气颗粒物中矿物颗粒物相组成及微观形貌的研究大致经历了3个阶段,主要体现在研究方法和手段的不断探索与进步,研究对象由总悬浮颗粒向PM_2.5甚至更细颗粒物以及由全颗粒分析向单颗粒分析转移,不断重视原生矿物变化及次生矿物生成机理研究。本文提出发生硫化现象的原生矿物及二次成因硫酸盐颗粒是未来研究的重要方向之一。     

宜昌市矿产资源特点研究

简要叙述了宜昌市自然经济状况,初步分析了区内矿产资源的区域成矿地质背景,并总结了其时空分布规律,重点从数量、质量、价值、分布以及它们在宜昌市国民经济和社会发展中的地位等方面总结了区内矿产资源的特点,从而筛选出优势矿产与潜在优势矿产.     

岷江上游某水电站工程边坡软岩的崩解特性研究

炭质岩层常作为主要岩层或者夹层频繁出现在广西各时代地层单元中,因其易风化裂碎、崩解软化及工程性质对环境敏感,给广西地区公路工程建设带来诸多复杂问题。通过既有地质资料搜集、野外地质调查、取样测试等研究手段,对广西地区炭质岩的分布及组合特征、矿物组成、有机质特征开展研究,并对炭质岩崩解的影响因素及相应工程措施进行了探讨。研究表明：(1)广西地区炭质岩从新元古界至古近系均有分布,主要包括24个地层单元,其基本物质组成以黏土矿物、石英和碳酸盐岩矿物为主,且有机质含量较高,属于中-高级烃源岩的炭质岩类;(2)炭质岩所含黏土矿物中的伊利石和伊/蒙混层、高含量有机质以及硫化物是炭质岩在自然暴露状态下发生崩解的主要物质因素;(3)炭质岩边坡发生崩解的主要原因可分为4类：构造活动、黏土矿物的吸水膨胀性和受热脱水性、有机质和还原性矿物氧化分解反应、自然因素的影响。相关研究成果可为炭质岩地区边坡工程、隧道工程及路基工程的设计施工及处治工作提供重要参考。     

Amino sugars in suspended particulate matter from the Bay of Bengal during the summer monsoon of 2001

Amino sugars (AS) are important constituents of organic matter. However, very little is known about their cycling in marine waters. In this research, we assessed the distribution and cycling of these compounds in waters of the Bay of Bengal. For this purpose, samples of suspended particu late matter (SPM) were collected from 8 depths (surface to 1000 m) at 6 locations during the 166th cruise of the ORV Sagar Kanya in the Bay of Bengal in July/August 2001. The SPM samples were analysed for particulate organic carbon (POC), particulate nitrogen (PN) and AS concentrations and composition. The AS varied between 0.4 and 17.5 nmol/l. Concentrations were high in the surface waters and generally decreased with increasing depth. AS concentration decreased from the south to north. AS accounted for 0.01 to 0.71% and 0.05 to 2.37% of POC and PN, respectively. Rapid decrease in AS-C% and AS-N% with depth indicates that these compounds were preferentially degraded relative to bulk POC and PN. The composition of AS suggests that glucosamine (GLU-N) and galactosamine (GAL-N) were present in the surface SPM samples, and their abundance decreased from surface downwards. Relatively, low values of GLU-N/GAL-N ratio indicate that the organic matter was mostly derived from the detritus of micro-organisms. Our data suggest that chitin, a polymer of the glucosamine produced by many marine organisms was not the major source of AS in the Bay. Rapid cycling of these compounds indicates their importance in the cycling of nitrogen in marine waters