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1.
孙琳婷  赵祯  唐建辉 《环境科学》2020,41(9):4069-4075
采用超高效液相色谱/质谱联用(UPLC/MS-MS)分析了我国重要的氟化物工业园区周边河流——辽宁细河(阜新段)、山东小清河(淄博段)和长江(江苏常熟段)表层沉积物中全(多)氟烷基化合物(PFASs)的污染状况.细河表层沉积物中,PFASs含量范围(以干重计,下同)为15.8~2 770 ng·g~(-1),全氟丁烷磺酸(PFBS)和六氟环氧丙烷二聚酸(HFPO-DA)是主要污染物;小清河表层沉积物中,PFASs含量为12.2~7 853 ng·g~(-1),全氟烷基辛酸(PFOA)和HFPO-DA为主要污染物;长江表层沉积物中,PFASs含量为9.20~35.9 ng·g~(-1),全氟十四酸(PFTeDA)和6∶2氟调磺酸(6∶2FTS)为主要污染物.工业园区废水排放(点源污染)是本研究中3个区域PFASs的主要来源. 3个区域PFASs含量及组成差异明显,与工业园区生产规模和产业类型有关.PFASs含量及各组分含量与TOC、沉积物粒径没有显著相关性,PFASs各组分间相关性也有差异,说明PFASs在沉积物中的富集过程与多种因素有关.  相似文献   

2.
通过培养实验测定了菲律宾蛤仔(Ruditapes philippinarum)DIN和PO34-的排泄率和生物扰动作用对胶州湾沉积物-水界面营养盐交换通量的影响,探讨了菲律宾蛤仔养殖对沉积物-水界面生源要素迁移的影响.研究表明,菲律宾蛤仔能够排泄DIN和PO34-,但其生物扰动能够改变沉积物中生物地球化学过程,减少排泄物中的DIN和PO34-向水体释放.在生物扰动作用下,菲律宾蛤仔排泄的DIN和PO34-中,仅有37%(DIN)和34%(PO34--P)最终释放到水体中.在考虑生物扰动作用的影响后,养殖菲律宾蛤仔每年从水体滤除的生源要素中仅有19%的氮和17%的磷以无机营养盐形态完成再生过程返回到水层中,其余部分以渔获量、生物难于利用形态或埋藏的沉积颗粒形态从水层中清除.菲律宾蛤仔生物扰动条件下沉积物向水层释放Si∶N∶P的速率比约为5∶18∶1,其中Si∶N和Si∶P比远低于菲律宾蛤仔从水体中滤除的颗粒物.因此菲律宾蛤仔养殖能够加速生物硅沉积,加剧胶州湾水体中Si限制.  相似文献   

3.
黄河中游(渭南-郑州段)全/多氟烷基化合物的分布及通量   总被引:2,自引:2,他引:0  
本研究收集黄河中游(渭南—郑州段)表层水样品,利用高效液相色谱质谱串联的方法分析了水相和颗粒相中的28种全氟和多氟烷基化合物(PFASs).结果表明,水相和颗粒相中Σ28PFASs的含量分别为18.4~56.9 ng·L~(-1)和26.8~164ng·g~(-1)(以干重计).水相和颗粒相中以全氟己酸(PFHx A)为主要污染物,分别占总含量的27%和16%,且3H-全氟-3-(3-甲氧基丙氧基)丙酸(ADONA)、氯代多氟醚基磺酸(6∶2和8∶2 Cl-PFESA)在颗粒相均有检出,表明PFASs替代品的生产和使用逐渐增多.PFASs在水相-颗粒相中的lg Kd变化范围为2.95±0.553(PFPe A)~3.85±0.237(8∶2 FTUCA),颗粒物吸附氟调聚羧酸(FTCAs)和不饱和氟调聚羧酸(FTUCAs)的能力随碳链长度的增长而增加,全氟烷基磺酸(PFSAs)较全氟烷基羧酸(PFCAs)更容易被颗粒物吸附.黄河郑州—渭南段PFASs的通量呈现先降低后增加的趋势,表明该河段接纳了来自上游及支流的污染输入.此外,结果表明水相中的PFASs通量大于颗粒相.  相似文献   

4.
深圳近岸海域全氟化合物的污染特征   总被引:5,自引:3,他引:2  
为探究深圳近岸海域全氟化合物(perfluorinated compounds,PFCs)的污染特征,2013年9月采集了深圳近岸(离岸﹥2km)10份表层海水和7份表层沉积物.采用固相萃取分离、富集,结合高效液相色谱-质谱联用的方法测定了其中16种PFCs的含量.结果表明,表层海水中有10种PFCs不同程度地检出,包括C4、C6和C8全氟磺酸盐(perfluorinated sulfonates,PFSAs)和C5~C11全氟羧酸(perfluorinated carboxylic acids,PFCAs).ΣPFCs质量浓度范围在1.74~14.7 ng·L-1之间,其中PFBS、PFOS和PFOA是主要的PFCs.ΣPFCs质量浓度分布呈西高东低的态势,伶仃洋和深圳湾ΣPFCs质量浓度显著高于大亚湾和大鹏湾(P0.05),距岸越远ΣPFCs质量浓度越低.表层海水中PFCs可能主要来自于近岸污水的排放以及河流入海的输入.表层沉积物中有8种PFCs不同程度地检出,包括C6和C8PFSAs和C5,C6,C8~C11PFCAs.ΣPFCs含量范围在2.22~2.62μg·kg-1之间,其中PFOS是主要的PFCs.ΣPFCs含量变化很小,可能主要来自对上覆海水中PFCs的吸附.沉积物吸附PFCs的能力随碳链长度增加而增强,且相同碳链长度的情况下,PFSAs较PFCAs更易于被吸附.此外,不同近岸海域PFCs质量浓度比较结果表明,深圳近岸海域表层海水PFBS污染较为严重,而沉积物PFOS含量与其他海域相差不大.  相似文献   

5.
研究污染物在沉积物-水界面的扩散趋势对于开展其环境风险评估具有重要作用。本研究基于大连湾海域海水和沉积物样品中全氟烷基化合物(PFASs)的含量数据,应用变异系数(Cv)分析了浓度分布的空间变异程度,应用逸度分数(ff)分析了PFASs在沉积物-水界面扩散趋势,应用响应系数(RC)分析了有机碳含量对扩散趋势的影响。结果表明:大连湾海域海水和沉积物中9种PFASs的总浓度均为中等变异;在沉积物中的浓度空间差异略大,可能受历史排放污染物残留及污染事故的影响。在海水-沉积物界面扩散过程中,全氟烷基磺酸类和全氟烷基羧酸类化合物呈现相同的扩散特性,总体表现为ff值随PFASs链长的增加而逐渐降低的趋势。短链PFASs在大连湾海域倾向于存在于水体中,而长链PFASs倾向于扩散到沉积物中。有机碳是影响PFASs在沉积物-水界面扩散趋势的重要参数,且对长链PFASs的影响更明显。全氟辛烷磺酸作为一种持久性有机污染物在大连湾海域中主要处于平衡状态。  相似文献   

6.
为探究全氟和多氟烷基化合物(PFASs)及典型异构体在人血清中的暴露特征,利用高效液相色谱串联质谱法(HPLC-MS/MS)分析检测了60个人类血清样本中包括全氟辛烷羧酸(PFOA)与全氟辛烷磺酸(PFOS)异构体在内的16种PFASs.结果表明,除PFOA的异构体4m-PFOA与5m-PFOA外,所有目标PFASs均被检出.ΣPFASs的血清浓度为2.15~77.22 ng·mL-1,n-PFOS是血清中贡献率最高的PFASs,其次为3+5mPFOS、4m-PFOS、n-PFOA及全氟己烷磺酸(PFHxS),PFOS所有的异构体与PFHxS、PFNA之间均存在显著的正相关关系.探究不同性别和年龄段的人类血清的PFASs发现,男性血清中的PFASs浓度显著高于女性,高年龄段人群血清中的PFASs浓度高于低年龄段人群.健康风险表征显示,血清中所有的PFASs单体的风险熵值HQ均小于1,PFASs的总和危险指数HI也小于1,血清中的现有浓度的PFASs对造成人类肝毒性和生殖毒性的风险程度较低,肝毒性与生殖毒性HI的主要贡献者均为n-PFOS,其次为3+5m-PFOS与...  相似文献   

7.
成都饮食中全氟化合物的污染特征及健康风险评估   总被引:1,自引:0,他引:1  
为了解成都市居民通过饮食暴露于全氟化合物(Perfluoroalkyl Substances, PFASs)的情况,本研究通过调查统计成都市居民的主要饮食情况,选取米、蔬菜、牛奶、鸡蛋、鱼和猪肉6类饮食为研究对象,采用超高效液相色谱-串联质谱法对样品中17种PFASs进行检测.结果显示,所有饮食中均检出PFASs,说明PFASs在饮食中普遍存在.鸡蛋中的∑PFASs含量最高,达(155±25.4) ng·g~(-1)(湿重,下同);白菜的∑PFASs含量最低,仅为(0.101±0.026) ng·g~(-1).大部分样品中以全氟辛烷羧酸(Perfluroroocantanoic Acid,PFOA)为主,其次为短碳链的全氟羧酸(Perfluoroalkyl Acids,PFCAs).其中,鸡蛋蛋黄中∑PFASs的含量为(600.0±98.6) ng·g~(-1),远高于蛋清中的含量(0.606±0.101) ng·g~(-1),且蛋黄中主要为全氟辛烷磺酸(Perfluorooctane Sulfonate,PFOS)(98.1%).通过风险评估可以得出,成都市居民对PFOS和PFOA的日摄入量分为85.6 ng·kg~(-1)·d~(-1)和4.38 ng·kg~(-1)·d~(-1),低于欧盟食品安全局推荐的每日最大摄入量,不会对成都市居民造成即时伤害.  相似文献   

8.
大连典型滩涂养殖区菲律宾蛤仔体内Pb含量及溯源   总被引:1,自引:0,他引:1  
为了评价滩涂养殖区贝类体内重金属Pb的污染情况,并追溯贝类体内Pb的可能来源,本研究选取黄海北部的大连金石滩、大李家和皮口3个典型滩涂养殖区为监测点,以滩涂养殖区内的菲律宾蛤仔为周年监测对象,并采用稳定同位素示踪技术追溯菲律宾蛤仔体内Pb的可能来源。研究结果表明,大连典型滩涂养殖区海水中Pb的周年监测结果均优于国家二类海水水质标准,表层沉积物中Pb的潜在生态风险性属于轻微生态危害程度,菲律宾蛤仔体内Pb的含量周年内均小于无公害水产品的限量标准。同时,菲律宾蛤仔体内Pb稳定同位素206Pb/207Pb值与表层沉积物的比值相接近,表明菲律宾蛤仔体内Pb可能主要来源于表层沉积物。  相似文献   

9.
采用超高效液相色谱-质谱联用仪分析了四川省10个地区自来水中12种全氟化合物(perfluoroalkyl substances, PFASs)的含量,其中全氟化合物浓度水平最高的是宜宾地区,∑PFASs为41.2 ng·L~(-1),浓度水平最低的是绵阳地区,为4.17 ng·L~(-1).全氟辛烷羧酸(perfluroroocantanoic acid,PFOA)是四川地区自来水中主要的PFASs,占总全氟化合物的28%~89%(宜宾地区8.6%),其次为全氟己酸(perfluorohexanoate,PFHxA)、全氟辛烷磺酸(perfluorooctane sulfonate, PFOS)和全氟壬酸(perfluorononanoate,PFNA),这表明自来水中的主要污染物为中短碳链(C≤10)的全氟化合物.另外,通过计算PFASs的危险商值(risk quotients, RQ),发现四川地区自来水中PFOA、PFOS、PFHxS、PFBS和PFHxA的风险商值均小于1,不会对当地居民带来直接的健康风险.  相似文献   

10.
王世亮  曹雪稚 《环境科学》2020,41(12):5428-5437
近年来,滨海旅游度假区蓬勃发展,其水体环境质量对人体健康有直接影响;全氟化合物(perfluoroalkyl substances,PFASs)在各环境介质中普遍被检出,因其潜在的毒性而引起广泛关注.以山东省20个滨海旅游度假区水和沉积物为对象,对其中12种典型PFASs的污染特征及其潜在生态风险进行了系统研究.结果表明,在20个度假区所有水体和绝大多数沉积物样品中12种PFASs都被检出;水和沉积物中PFASs的平均含量分别为67.91 ng·L-1和5.89 ng·g-1,全氟辛酸(perfluorooctanoic acid,PFOA)和全氟辛烷磺酸(perfluorooctanesulfonic acid,PFOS)都是含量占绝对优势的物质;不同度假区水和沉积物中PFASs总含量∑PFASs及各同系物的含量具有明显差异;在不同度假区水/沉积物体系12种PFASs的分配系数差异明显,长链PFASs(碳原子数≥7)具有更大的分配系数;城市工业废水和生活污水的排放是度假区水和沉积物PFASs的主要来源,水体盐度和沉积物有机质含量不是PFASs在水/沉积物之间分配的决定性影响因素;所有滨海旅游度假区水体环境中,PFOS和PFOA可能存在较大潜在生态风险.  相似文献   

11.
All species included in the Polysphincta genus-group develop as ectophagous parasitoids of active spiders, killing their hosts prior to pupation. However, little information regarding natural history and ovipositing behavior of most species are available. In this study we inspected 85 webs of Araneus omnicolor to evaluate the frequency of parasitism and host size preferences of the wasp Hymenoepimecis sp. We also described the web characteristics of normal and parasitized spiders and the wasp ovipositing behavior. About 41% of the adult females of A. omnicolor inspected were parasitized. The highest incidence of parasitism was observed among relatively small females while no egg or larva was found in large individuals. Araneus omnicolor builds a strong web composed of an orb and barrier threads, where the spider rests within a curled leaf. The parasitoid larva builds its cocoon within this refuge, and modified cocoon webs were not observed. The ovipositing behavior of Hymenoepimecis sp. was very similar to that of Hymenoepimecis argyraphaga parasitizing Leucauge argyra, including the position of the sting, the killing of a previously attached larva, and the expelling of the egg from the base of the ovipositor.  相似文献   

12.
植物不同器官水、碳、氮、磷等元素含量及其生态化学计量特征能够反映植物的生态策略及其环境适应性。本研究以黄土高原两种乡土树种油松(Pinus tabulaeformis)和柴松(Pinus tabulaefirmis f.shekanensis)为研究对象,分析了研究区两种树种水、碳、氮和磷在不同器官的含量及其生态化学计量特征,探讨了两种树种基于水、碳、氮和磷分配格局的生态适应策略。结果表明:(1)油松和柴松对水分和碳素的分配格局总体表现为根和叶最大,其次为枝和干,树皮最小;对氮、磷的分配格局则表现为叶片显著高于其他器官。(2)油松将更多的水和氮分配给叶、根等生产性器官,而柴松将更多的水和碳分配给枝、干等防御性器官,反映了柴松较油松具有更加保守的生长策略,能够更好适应逆境条件。(3)植物器官不同元素间通过相互耦合后可以表现出较好的相关性,反映了植物元素之间具有高度复杂的协同关系,这种协同关系的体现形式可能与植物类型及其对外界环境变化的生长适应策略密切相关。  相似文献   

13.
Cyanobacteria, specifically Microcystis, usually form massive blooms in eutrophic freshwater lakes. Cyanobacterial samples were collected from eight sites of both Lake Taihu and Lake Chaohu in late summer to determine the diversity and distribution pattern of cyanobacteria and Microcystis in large, shallow, entropic lakes with significant spatial heterogeneity and long-term Microcystis bloom. Molecular methods based on denaturing gradient gel electrophoresis and clone library analysis were used. A similar heterogeneous distribution pattern of cyanobacteria in both lakes was observed. Most parts of these two lakes with high trophic level were dominated by Microcystis. However, in the regions with low trophic levels as well as low concentrations of chlorophyll a, Synechococcus occupied a considerable percentage. Different morphospecies and genotypes dominated the bloom-forming Microcystis populations in these two lakes. Microcystis viridis and Microcystis novacekii were dominant in Lake Chaohu, whereas Microcystis flos-aquae was dominant in Lake Taihu. Only 2 of the13 Microcystis operational taxonomic units were shared between these two lakes. Analysis of molecular variance based on 16S to 23S internal transcribed spacer sequences indicated the significant genetic differentiation of Microcystis between these two lakes (Fst = 0.19, p < 0.001). However, only 19.46% of the genetic variability was explained by the population variation between lakes, whereas most (80.54%) of the genetic variability occurred within the lakes. Phylogenetic analysis revealed no phylogeographic structure of Microcystis population in these two lakes, as illustrated by their cosmopolitan nature. Our results revealed that spatial heterogeneity within lakes has more impact on the cyanobacterial diversity than geographical isolation in a local scale.  相似文献   

14.
从太湖水华腐烂蓝藻中筛选出一株能够降解MC-LR的细菌,将其编号为Q3.经形态、生理生化及16S rRNA基因序列分析鉴定为缺陷短波单胞菌(Brevundimonas diminuta).研究发现,在实验条件下该菌能以MC-LR为唯一碳源和氮源生长;7 d内可将初始浓度为0.96 mg·L-1的MC-LR降解为0.37 mg·L-1,降解效率达到61.5%.同时,本研究首次发现缺陷短波单胞菌能够降解藻毒素,并且在此菌种中扩增出了降解过程的关键基因mlr A,推测该菌可能与已报道的Sphingomonas sp.ACM-3962等菌具有相同的降解机制.  相似文献   

15.
Most species of the rove beetle genus Stenus employ the spreading alkaloid stenusine as an escape mechanism on water surfaces. In the case of danger, they emit stenusine from their pygidial glands, and it propels them over the water very quickly. Stenusine is a chiral molecule with four stereoisomers: (2′R,3R)-, (2′S,3R)-, (2′S,3S)-, and (2′R,3S)-stenusine. The percentile ratio of these four isomers is only known for the most common species of the genus: Stenus comma. With the intention of determining the stereoisomer ratios of five additional species from the two subgenera, Stenus and Hypostenus, we used GC/mass spectrometry measurements with a chiral phase. The results showed that the ratio differs among the genus. These findings can be a basis for chemotaxonomy. It is also possible that the biological function of stenusine, e.g., as antibiotic or fungicide, varies with changing stereoisomer composition.
Inka LusebrinkEmail:
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16.
1株扑热息痛降解新菌株的选育及其代谢特性研究   总被引:2,自引:1,他引:1  
通过选择性富集培养,从活性污泥样品中选育到1株能以扑热息痛为唯一碳源生长的好氧细菌F1.根据菌株F1的形态特征、生理生化特性、16S rRNA基因序列分析及和Biolog测试,初步鉴定为亲铜(Cupriavidus necator)菌属.菌株F1降解扑热息痛最适pH值和温度分别为7.0和30℃;菌株降解扑热息痛的过程遵...  相似文献   

17.
Female houseflies, Musca domestica (Diptera: Muscidae), lay their eggs in ephemeral resources such as animal manure. Hatching larvae compete for essential nutrients with fungi that also colonize such resources. Both the well-known antagonistic relationship between bacteria and fungi and the consistent presence of the bacterium Klebsiella oxytoca on housefly eggs led us to hypothesize (1) that K. oxytoca, and possibly other bacteria on housefly eggs, help curtail the growth of fungal resource competitors and (2) that such fungi indeed adversely affect the development of housefly larvae. Bacteria washed from housefly eggs significantly reduced the growth of fungi in chicken manure. Nineteen bacterial strains and ten fungal strains were isolated from housefly eggs or chicken manure, respectively. Co-culturing each of all the possible bacterium–fungus pairs revealed that the bacteria as a group, but no single bacterium, significantly suppressed the growth of all fungal strains tested. The bacteria's adverse effect on fungi is due to resource nutrient depletion and/or the release of antifungal chemicals. Well-established fungi in resources significantly reduced the number of larval offspring that completed development to adult flies. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

18.
Fire is an important community wetland management tool in Indonesia, but its increasing use in the wetlands of southern Sumatra is degrading the landscape and diminishing household incomes and livelihood options. We studied evolving community land and fire use, resource and livelihood impacts on two sites of roughly 250 km2 each using satellite image analysis and biological and socio-economic surveys. Uncontrolled fire use expanded over time in relation to sonor or swamp rice cultivation, logging, fishing, grazing, and annual cropping on drained wetlands. As a result, most of the landscape has been subject to repeated fires of varying intensities, more extensive in El Niño years. Direct burning by companies played a smaller transitory role in fire ignition over the two decades. But company activities and other large-scale developments contributed to expanding community fire-based land use by bringing in more people, improving access to remote wetlands or making them more flammable. Widespread, repeated fires have transformed the landscape from mature high swamp forests to uniform stands of fire-resistant Gelam (Melaleuca cajuputi) forests and thickets, open savannas and grasslands. These new types of land cover are also degrading. Local communities have rapidly adapted to the changing resources and new opportunities. Logging and fishing declined in importance, and sonor and harvesting of Gelam expanded. But resource depletion has led to falling incomes and fewer livelihood options. The impacts extend beyond local areas as workers migrate into neighbouring forests to extract resources. Large-scale developments, community fire-based management practices and landscape transformation are spreading from accessible to formerly more remote wetlands.  相似文献   

19.
畜禽粪便直接农用引起的重金属污染是社会普遍关注的问题,探索如何有效降低畜禽粪便重金属生物有效性的技术是急需解决的难题.本文通过分析鸡粪(CM)裂解前后Mn、Cu、Zn和Cr等4种重金属形态分布变化,并采用林地大型盆栽试验研究添加CM和鸡粪炭(CMB)处理对湿地松地上部分重金属吸收状况的影响.结果表明,与CM直接还田相比,添加CMB(400℃)处理降低Mn、Cu和Zn在湿地松地上部分的吸收量和富集系数,而处理之间植株Cr元素的吸收量和富集系数差异不显著. Tessier连续提取结果表明, Mn、Cu和Zn的交换态含量分别由CM的94.8、10.0和34.9 mg·kg~(-1)显著降为CMB的16.6 mg·kg~(-1)、未检测出和1.8 mg·kg~(-1). CM裂解成CMB后, Cr元素残渣态含量显著提高.从元素质量守恒来看, CM制成CMB后Mn、Cu、Zn和Cr损失率分别为29.3%、35.6%、33.5%和3.3%.裂解油中Mn、Cu、Zn和Cr的金属总量分别占CM金属损失量的51.7%、53.0%、32.9%和13.1%. CM裂解成CMB后,91.7%的交换态Mn、几乎100%交换态Cu和97.5%的交换态Zn会随裂解转化为铁锰氧化态、有机结合态和残渣态形式或挥发而降低有效性. 1年盆栽试验结果表明,在CMB处理中,土壤Mn、Cu和Zn交换态含量显著低于CM处理.相关性分析发现,植物体内重金属吸收量与土壤金属有效态含量显著相关,而与总量相关性不明显.由此可见,将鸡粪制成鸡粪炭是一种有效降低Mn、Cu和Zn生物有效性的途径.  相似文献   

20.
Mechanical treatment and prescribed fire were used to restore a mixed conifer stand (Picea-Abies-Pinus) following mortality from an outbreak of Siberian moth (Dendrolimus superans sibiricus). Moth-killed stands often become dominated by Calamagrostis, a sod-forming grass. The large amount of woody debris and the sod hinder coniferous seedling establishment and development as well as creating conditions favorable to the establishment and propagation of wildfires. Fire has been demonstrated to be an effective method of reducing woody debris and eliminating sod, but the random nature and timing of wildfires often do not create conditions favorable for conifer regeneration. Our study was conducted in a mature fir dominated stand that died during an outbreak 6–8 years previously with most of the dead trees still standing. A bulldozer drove through the stand downing standing snags in late summer with 15–20 m between passes. Snags knocked down by the bulldozer and additional snag fall throughout the following winter increased downed dead wood 50–60% and large downed dead wood 80% compared to an adjacent untreated area. In June, a prescribed fire was set and fuel load consumption averaged 70%. Average soil temperatures during the burn ranged from 47 C at a depth of 2 cm to 10 C at 10 cm; hot enough to kill the grass. Following treatment, the potential for wildfire was reduced and the area was suitable for either natural conifer regeneration or planting without further mechanical site preparation.  相似文献   

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