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1.
对北京地区具代表性的环境功能区表层土壤饱和烃的组成与分布特征进行分析,并讨论了饱和烃污染物的来源。研究结果表明,在不同环境功能区表层土壤样品中均检测到了正构烷烃、类异戊间二烯烷烃、烷基环己烷和甾、萜烷烃等饱和烃化合物,其中正构烷烃和类异戊间二烯烷烃占优势。不同环境功能区和土壤类型的表层土壤样品中饱和烃的组成、分布特征和来源均存在明显差异,其中城区土壤受人为污染最为严重。表层土中饱和烃类化合物的来源比较复杂,既有人为污染源,又有天然来源。其中,中-低碳数正构烷烃主要是人为来源,高碳数正构烷烃主要为生物来源;类异戊间二烯烷烃、烷基环己烷和甾、萜类化合物则主要来源于矿物油、化石燃料和生物质不完全燃烧的产物等。  相似文献   

2.
分子标志物参数在识别土壤多环芳烃(PAHs)来源中的应用   总被引:6,自引:0,他引:6  
土壤中PAHs污染物的成因十分复杂,常见的污染源包括生物质的高温降解产物、石油等化石燃料及其不完全燃烧产物等,其输入方式主要有大气中所含PAHs的干、湿沉降、水体输入、固体废弃物排放等。不同成因的PAHs组成特征有一定差别,并可能具有独特的分子标志物或分子化合物组合特征,由此,可以根据环境介质中PAHs的组成特征判断污染物来源或成因类型。目前,分子标志物特征参数已成为追踪PAHs污染来源的有效手段。介绍了近年来国内外在运用PAHs分子标志物特征参数识别土壤中PAHs污染源方面的主要研究进展、应用潜力及存在的问题。  相似文献   

3.
针对影响水库水质的主要污染物以及污染物的来源,采用水质单因子评价法与水质综合污染指数评价法相结合的方式,分析水库水质特征。结果表明:所监测的3个断面水环境质量逐年好转。影响水库水质的主要限制因素是总氮的输入,农业面源营养流失是水库的主要污染源。发现污染源并有效的治理可以显著提高水库水环境质量,有效指导水环境修复。  相似文献   

4.
利用氮、氧稳定同位素识别地下水硝酸盐污染源研究进展   总被引:1,自引:0,他引:1  
氮污染特别是地下水硝酸盐污染已成为一个相当普遍而重要的环境问题。地下水硝酸盐污染与人类健康和环境安全密切相关。为控制地下水硝酸盐污染,最根本的解决办法就是找到硝酸盐的来源,减少硝态氮向地下水的输送。由于不同来源的硝酸盐具有不同的氮、氧同位素组成,人们利用NO3-中δ15N和δ18O开展了硝酸盐污染源识别研究。本文综述了利用氮、氧同位素识别地下水硝酸盐污染源及定量硝酸盐污染源输入的研究进展及目前存在的问题,并提出几个值得重视的研究方向。  相似文献   

5.
汾河下游丰水和枯水期的河流硝酸盐污染来源特征   总被引:2,自引:0,他引:2  
[目的]对汾河径流丰水期和枯水期的河流硝酸盐污染来源特征进行对比分析和研究,为汾河下游氮源污染治理提供理论支持。[方法]通过研究2018年汾河下游水体硝酸盐及其氮、氧同位素不同时期的变化,分析排入河流的硝酸盐来源雨期性变化特征,并引入IsoSoure模型,定量计算各污染源对汾河下游水体硝酸盐的贡献。[结果]在丰水期和枯水期,δ~(15)N值变化范围为3.45‰~11.19‰,δ~(18)O值变化范围为-0.72‰~3.17‰,硝酸盐污染源主要为农业化肥、土壤有机氮、生活污水与粪便;硝酸盐污染源主要与汾河下游周围土地利用类型相关,丰水期临汾段与M_5采样点硝酸盐污染源主要为粪便和污水,分别占比为58%,40%,72%和58%,M_6—M_9段农业化肥贡献率最高,占比分别45.4%,62%,56.6%,56.5%。枯水期所有采样点硝酸盐污染源贡献率最高的都为粪便和污水,占比为40%~73%。[结论]汾河径流硝酸盐污染来源主要为农业化肥、土壤有机氮、生活污水与粪便,并且污染来源与土地利用类型有很强相关性,不同水期硝酸盐污染来源大多为粪便和生活污水,差别主要体现在M_6—M_9取样点,丰水期主要污染物为农业化肥,而枯水期为粪便与生活污水。  相似文献   

6.
陕西省丹汉江流域面源污染现状及防治对策   总被引:3,自引:0,他引:3  
面源污染是丹江口水库水质安全的主要威胁。为了探寻陕西省丹汉江流域面源污染的总量及其组成,采用统计调查、参数计算、对比分析的方法,对目前陕西省丹汉江流域主要面源污染物的入河量及其贡献率等方面进行了研究。结果表明,丹汉江流域CODcr、氨氮、总氮、总磷的年入河量分别为103 053,19 851,213 453和39 838t。生活污水及人粪尿是产生CODcr污染的最主要来源,水土流失是产生氮磷污染的最主要来源。面源污染物入河量与污染源的基数、污染物含量、污染物分散程度等因素有关。建议在治理面源污染过程中采取加大水土流失治理力度,开展新农村建设和推广生态清洁小流域治理模式等措施。  相似文献   

7.
杨逢乐  赵磊 《土壤与环境》2007,16(6):1627-1632
合流制排水系统降雨期间高污染溢流污水直接排入水体对水体质量有明显影响,其径流污染物输出特征和初期冲刷效应受排水区类型、面积、降雨特性等多种因素影响。为此,选取昆明市典型合流制排水系统明通河流域不同类型集水区进行降雨径流监测,研究合流制排水系统降雨径流污染物输出特征及初期冲刷效应。结果表明:合流制排水系统初期合流污水污染物质量浓度明显高于后期,不同污染物输出特征、形态差别较大,溶解态氮是N污染物的主要赋存形态,而P污染物主要以颗粒态形态存在。管道沉积物是合流污水重要的污染来源。年内次降雨污染物平均质量浓度以雨季初期降雨最高,中期降雨质量浓度最低,雨季后期质量浓度较中期略有上升。不同类型集水区N、P质量浓度排序为:居民区〉城市综合型〉综合型〉城郊结合型。降雨量是影响初期冲刷效应的关键因素,雨量大的降雨初期冲刷效应明显。  相似文献   

8.
城市地表径流污染及其全过程削减   总被引:15,自引:1,他引:15  
城市地表径流是影响城市水环境质量的第二大污染源,也是仅次于农业面源污染的第二大非点源污染源。随着城市工业废水和生活污水等点源治理力度的加大,城市地表径流污染问题将越来越突出。本文系统地阐述了城市地表径流污染产生的过程、污染特征、影响因素、污染物类型及其来源,并从径流量、污染物和径流总量等3个层面,以及从污染物产前、产中以及产后等3个环节全方位地探讨了城市径流污染的削减对策与措施。  相似文献   

9.
株洲市白马乡土壤和农作物重金属污染评价   总被引:18,自引:1,他引:18  
刘扬林  蒋新元 《土壤》2004,36(5):551-556,564
本文对株洲市白马乡土壤及其农作物中重金属含量进行了调查并对其污染进行了评价。结果表明:该乡土壤和作物均受到了不同程度的重金属污染,土壤达不到土壤环境质量二级标准要求,作物达不到食品卫生标准要求,土壤重金属污染因子主要为Cd,作物中主要重金属污染因子为Cd、Pb。附近清水塘工业区排放的大气污染物重金属尘是造成白马乡土壤和作物重金属污染的主要因素。不同测点土壤和作物污染程度差别极大,主要和各测点与最大重金属尘污染源距离的远近、方位及风向有关。  相似文献   

10.
用GC-MS分析了成都市不同方位区域内具有代表性的土壤和扬尘样品中饱和烃的组成与分布特征。研究表明,在土壤和扬尘中均检测出了丰富的正构烷烃和甾、萜烷化合物等饱和烃。正构烷烃在土壤和扬尘中差别明显,其浓度分别为7.54~40.37μg g-1和26.61~71.52μg g-1,峰形分别主要呈前峰型和后峰型。成都市土壤中正构烷烃含量的趋势是东>北>中>西>南,扬尘为南>西>东>中>北。在土壤和扬尘中均检测出包括C27~C29规则甾烷、重排甾烷和孕甾烷等甾烷系列化合物和萜类化合物,主要来源于化石燃料和生物质不完全燃烧的产物等。  相似文献   

11.
土壤溶解性有机碳(DOC)的影响因子及生态效应   总被引:18,自引:0,他引:18  
柳敏  宇万太  姜子绍  赵鑫 《土壤通报》2007,38(4):758-764
土壤溶解性有机碳(DOC)是陆地生态系统中极为活跃的有机组分,是土壤圈层与相关圈层(如生物圈、大气圈、水圈和岩石圈等)发生物质交换的重要形式。影响土壤中物质的溶解、吸附、解吸、吸收、迁移乃至生物毒性等行为之外,对温室气体CH4的排放、水体水质的污染、岩石圈的风化等的影响也不可忽视。本文以陆地生态系统的中的DOC为主体,探讨了DOC的生态环境意义及其对大气、水体和岩石圈的影响以及DOC对土壤管理措施的响应。  相似文献   

12.
The hydrocarbon fraction of 30 virgin olive oils was analyzed, focusing in particular on the sesquiterpenes. The oil samples were of different geographical origins and obtained from different olive varieties. The hydrocarbon fraction was isolated by silica gel column chromatography of the unsaponifiable fraction of the oils. The sesquiterpene hydrocarbons were then fractionated, on the basis of their degree of unsaturation, by AgNO3 TLC and silica gel AgNO3 column chromatography. The composition of the sesquiterpenes was more complex than previously reported. Among the 31 sesquiterpenes detected, 24 have been tentatively identified, by comparison of the linear retention indices on two capillary columns of different polarities and mass spectra with those reported in the literature. The total concentration of the sesquiterpenes in the oils analyzed ranged from about 2 to 37 ppm. Among the sesquiterpenes the more abundant were alpha-farnesene, alpha-copaene, eremophyllene, and alpha-muurolene. The alkenes present in the hydrocarbon fraction were isolated by TLC AgNO3 and characterized by GC-MS of their dimethyl disulfide derivatives. The series of n-Delta9-alkenes from C22 to C27, 8-heptadecene, and 6,10-dimethyl-1-undecene were detected. Among the n-alkanes, those with an odd number of carbon atoms predominated in all of the analyzed oils, the most common being C23, C25, C27, and C29. The concentration of the n-alkenes ranged from about 0.5 to 2 ppm, whereas for the n-alkanes the range was from 30 to 177 ppm.  相似文献   

13.
The history of diesel fuel spills into a sand aquifer was investigated using biodegradation signatures and biomarker compounds of the light non-aqueous phase liquid (LNAPL) petroleum hydrocarbons. Samples of the weathered LNAPL diesel from 28 monitoring wells, along with LNAPL from cores, in a 2 ha plume were characterised by GC–MS techniques. The relative extent of biodegradation was assessed using ratios of partially degraded and resistant compounds including n-alkanes (n-C17), pristane and phytane. Biomarkers cadalene and methyldibenzothiophenes were also used to differentiate two different crude oil sources (Middle Eastern and South-east Asian). Age relationships were also investigated from the LNAPL composition. Both the extent and distribution of biodegradation and biomarkers identified a recent spill into the aquifer and traced its spread within the existing LNAPL plume. Evidence of an older, discrete and more degraded spill was also identified within the larger plume. Importantly, these analyses also identified a loss of as much as 80% of spilled diesel mass through biodegradation and other natural attenuation processes. Oxidised hydrocarbon material immediately above the LNAPL in the profile and reduced pristane:phytane ratios at the top of the LNAPL profile, provide supporting evidence of aerobic biodegradation.  相似文献   

14.
The Mar Piccolo (surface area of 20.72 km2) is located in the Northern area of the Taranto town (Ionian Sea, Italy). It is an inner, semi-enclosed basin with lagoon features connected with the Mar Grande through two channels which are very important for water exchange. Mar Piccolo basin is subjected to urbanization, industry, agriculture, aquaculture and commercial fishing. Hence, it is important to have a temporal picture both of heavy metal content and of organic carbon and their distribution (hydrophobic fraction, hydrophilic fraction, humic compounds) to check the progress of pollution in time. Three sediment cores collected on the basis of the pollution sources have been analyzed. Both heavy metal and organic carbon concentrations underline the fact that the anthropogenic input is different in the three sites, and that in time the amount of pollutants coming into the Mar Piccolo have changed in different ways. The high amount of organic hydrophilic compounds present in sediments, both due to the small water depth and to the high accumulation rate, make the sediment site high in oxygen consumption due to a considerable chemical and biochemical transformations of organic matter.  相似文献   

15.
不同掺混比例生物柴油的非常规污染物排放特性   总被引:1,自引:0,他引:1  
为了实现柴油机的清洁燃烧,需要系统研究非常规污染物的生成机理与排放特性。根据羰基类、芳香烃类物质的理化性质特点,提出了柴油机非常规污染物高效快速的测量方法,采用不同掺混比例的生物柴油进行了柴油机台架试验,探讨了不同燃料、不同工况下柴油机非常规污染物的排放特性。结果表明,二硝基苯腙采样结合高效液相色谱技术,可以实现柴油机排气中15种羰基类污染物的快速准确测定,活性炭吸附结合气相色谱-质谱联用技术可以实现芳香烃污染物的定性定量分析;中、低负荷时,生物柴油掺混比例对柴油机总羰基排放的影响不大,随着负荷的增加,BD50(生物柴油和市售0#柴油按体积比1:1配制的调合油)和BD0(纯柴油)的总羰基排放呈升高趋势,BD100(以地沟油为原料的生物柴油)的总羰基排放有所降低;BD0的单环芳香烃最大排放浓度最高,3种燃料的气相多环芳香烃排放在低负荷和高负荷工况点存在"双峰"特征,三环菲约占所有环数多环芳香烃总量的44%,燃用生物柴油可降低柴油机约32%的多环芳香烃排放。该研究为柴油机非常规污染物的排放控制提供了参考。  相似文献   

16.
To evaluate the chemical fingerprint of hydrocarbons in airborneorganic matter in the arid environment of Alexandria City, Egypt,the compositions of aliphatic and aromatic compounds were determined in suspended particulate material collected from a street undergoing heavy traffic in central Alexandria and in bulkdeposition samples collected from a site representing an area increasingly influenced by human and industrial activities. Qualitative and quantitative characterizations of individual compounds were based on gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) analyses. More than 100 organic compounds are quantified in each sample, including n-alkanes, isoprenoids, polycyclic aromatic hydrocarbons(PAHs), sulfur-bearing heterocyclics, steranes/diasteranes, terpanes and aromatic steroids. The use of hydrocarbon profilesand ratios for identifying sources and processes is discussed.The molecular distribution of alkanes revealed that the mainsource of these compounds is from petroleum contamination withtrace input of vascular plant wax. The PAH profiles, especiallythe relative abundance of alkyl-PAHs and sulfur-containing heterocyclics, showed that PAHs are chiefly derived from trafficsources. The results further indicated that diesel vehicles aremore important PAH sources than gasoline vehicles. In addition,the source fingerprint of fossil fuel biomarkers such as steranes, terpanes and aromatic steroids agreed well with thefingerprint of unburned lubricating oil, which are probably contributed to vehicle exhaust emissions.  相似文献   

17.
The quality of three types of treated sludges (sludge from the paper recycling industry, and sewage sludge treated by composting with pruning waste and thermally dried) was assessed in this work. The amendments were physicochemically characterized and evaluated for their microbiological quality and for contamination with pollutants. All three organic amendments showed an absence of pathogens, so they are microbially suitable for agricultural use. The pollutants studied in the amendments included eight heavy metals and 83 organic compounds. Heavy metals, pesticides, polycyclic aromatic hydrocarbons, octylphenol, bisphenol A, and parabens were found in the organic amendments. The amount and type of contaminants depended on the sample sources and differed between samples from a single origin. The presence of some of the pollutants found has not been previously reported in organic amendments. The germination assay showed that these amendments may be applied to soil in controlled doses. As far as we know, this is the first reported study that has evaluated a great variety of pollutants (heavy metals, pesticides, persistent and emerging organic pollutants) in sludge from the recycled paper industry; moreover, studies in other waste products in which such a broad range of pollutants has been evaluated have been scarce until now due to the complexity of these matrices.  相似文献   

18.
土壤中溶解性有机质及其对污染物吸附和解吸行为的影响   总被引:55,自引:4,他引:55  
溶解性有机质(DOM)已成为环境科学、生态学和土壤科学等学科的研究热点。DOM对重金属、养分和有机污染物的环境化学行为有很大影响,因此开展DOM与污染物(或养分)之间相互作用的研究,具有重要的理论与实践意义。本文系统地评述了DOM的来源、组成、分级及其对土壤中污染物吸附一解吸行为的影响。尽管关于土壤中DOM的研究还不完善,许多工作也只是刚刚开始,至今对土壤中DOM的性质、组成和分类方法等问题都不是很清楚,但现有的结果已经表明,DOM是土壤圈中一种十分活跃的重要化学组分,它对土壤中化学物质的溶解、吸附、解吸、吸收、迁移和生物毒性等行为均有显著的影响。  相似文献   

19.
N-alkanes were measured both in dissolved and particulate-adsorbed phases of water samples collected from five stations located along Shatt al-Arab River in Iraq. The aim of this study was to provide a background information on the presence, origin, and distribution of n-alkanes in the waters of Shatt al-Arab River. Total concentrations of n-alkanes were lower in the dissolved phase (29.37 (μg L?1) than in the particulate-adsorbed fraction (17.62 μg g?1 dw). Distribution of n-alkanes in both fractions is characterized by two distinct patterns. First, for C compounds numbered C14 to C22, the ‘odd’ numbered hydrocarbons were slightly more abundant with C17 being the most concentrated. The second is shown within n-alkanes greater than C22. In these the ‘odd’ numbered hydrocarbons show even greater predominance indicating that much of the n-alkanes in the waters of Shatt al-Arab, may have originated from aquatic biogenic sources; i.e., diatoms, algal forms, bacterial activities, and higher plants. The CPI values were found to be from 0.99 to 1.98 in the dissolved fraction and from 0.70 to 2.10 in the particulate fraction. Petroleum hydrocarbon inputs and urban related oil discharges (anthropogenic pollution) may also have contributed to the input of n-alkanes in Shatt al-Arab, particularly near the city of Basrah (St. IV). Total concentrations at station IV were much higher (8.40 μg L?1 and 5.80 μg g?1) than that for the most upstream station, # I, (3.20 μg L?1 and 1.48 μg g?1) and decreased again further downstream at station V (7.10 μg L?1 and 4.32 μg g?1). The CPI values were around 1.0 in station IV. In a conclusion, results obtained in this study indicate that the n-alkanes in the waters of Shatt al-Arab River are of aquatic biogenic and anthropogenic (petroleum related) origins.  相似文献   

20.
Results of a comprehensive study are presented on the spatial and depth-related distribution of persistent organic pollutants (POPs) in sediments of the Brno reservoir, Czech Republic. Based on sedimentological observations, three major historic phases were identified related to the evolution of the depositional environment, flow rate, and material input. Data on organic carbon, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine pesticides showed specific distribution patterns in a 3-m-deep core. The analysis of the depth trends of the geochemical data combined with sedimentology made it possible to distinguish between remote sources of the pollutants, early weathering alterations of POPs, transport by river associated with organic matter as sorbent on one hand, and local sources weakly related to lithology on the other hand. The integrated sedimentological and environmental geochemical archive provided an improved dynamic view of the pollution in historical terms.  相似文献   

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