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1.
苯并(a)芘致毒的鱼的分子生态毒理学指标研究   总被引:11,自引:1,他引:10       下载免费PDF全文
通过测定典型的多环芳烃类物质苯并(a)芘(BaP)致毒后鱼体内几种重要分子生态毒理学指标的变化,来反映苯并(a)芘致毒对鱼体的影响.结果表明,肝脏ATPase活性降低,GST活性升高,DNA加合物相对标记水平(RAL)也增大,而EROD活性没有明显改变.这说明苯并(a)芘致毒对鱼体正常生命活动产生了重大影响,并具有潜在的致癌性.  相似文献   

2.
研究了将青鳉鱼长期暴露于不同浓度的全氟羧酸类物质全氟十三酸(PFTriDA)后的器官分布和富集系数.结果显示, PFTriDA最高富集在性腺;其次是卵、肝脏;浓度最低的部分是残体.除了性腺之外,该器官分布与野生中华鲟的一致.在相同暴露浓度下,雄鱼体内各器官的PFTriDA的含量高于雌鱼,机理模型计算进一步表明高母子传递系数是造成雌雄差异的可能原因.随着PFTriDA暴露浓度的升高,鱼体内同一器官的生物富集系数(BCF)呈现下降趋势.  相似文献   

3.
研究了叔丁基对羟基茴香醚(butylated hydroxyanisole,BHA)和诺氟沙星(norfloxacin,NFLX)对剑尾鱼的急性毒性及其肝脏谷胱甘肽硫转移酶(GST)、丙二醛(MDA)、过氧化氢酶(CAT)及7-乙氧基异吩恶唑酮-脱乙基酶(EROD)活性的影响.结果表明,BHA和NFLX对剑尾鱼毒性大小分别属于高毒和低毒.BHA的暴露浓度为0.20mg.L-1和0.04mg.L-1时,GST和CAT活性诱导分别达到最大值;NFLX的暴露浓度为5mg.L-1时,GST和CAT均受到最大程度的诱导.随着BHA和NFLX暴露浓度的增加,GST和CAT呈现出先诱导后抑制的典型"钟型曲线"变化规律,而MDA含量和EROD活性则逐渐增加.其中,MDA和EROD响应较为敏感,适合作为BHA和NFLX暴露的生物标记物.雌雄个体酶响应的敏感程度存在一定的差异,雄性个体比雌性个体敏感.  相似文献   

4.
Aspects of the trophic attributes of the mudskipper, Periophthalmus barbarus occurring in the mangrove swamps of Imo River Estuary, Nigeria, were investigated during a 12-month period (April, 1992-March, 1993). Feeding intensity increased with size, it was higher in the dry season(November-April) than in the wet season(May-October), monthly changes in the indices of feeding intensity were significantly correlated. Major food objects comprised detritus and benthic algae; crustaceans, insects, macrophyte matter and sand grains were minor food objects while fish, molluscs, Chilopoda, nematodes and fungi were unconsciously devoured objects. Diet varied seasonally; algae and sesarmid crabs were generally more in the dry season than during the rains whereas FPOM and fish increased in the wet over dry season.The mudskipper display a high degree of euryphagy and can be considered as a generalist and an omnivore. The lower trophic status of P.barbarus qualifies it as a good aquaculture candidate. Food richness was higher in big-sized class(BSC) than small-sized class(SSC). Sizebased and seasonal variations were not apparent in food richness. Diet breadth was higher in the BSC than the SSC, there was dry season increase in diet breadth.  相似文献   

5.
增蓝剂溶水后降低水下光照度,减弱入射光中370~440nm和530~680nm波段透射光.分析增蓝剂在0.1,1,5mg/L浓度及0.4,0.7,1m水深条件下,对自然水体原生藻类生长抑制效果,并测定其生物毒性.结果表明:在增蓝剂作用下水下光照度衰减明显,衰减系数(k)从0.25m-1增至0.7m-1.水深为0.4,0.7m时,增蓝剂抑藻效果显著(P<0.05),0.1,1,5mg/L浓度对藻类抑制率在第6d后迅速上升,在15d后稳定在65%以上,增蓝剂在0.4m水深抑藻效果较好.当水深至1m时,21d抑藻效果较差.急性毒性试验表明,增蓝剂对斑马鱼96hLC50为442.8 mg/L.  相似文献   

6.
蠕虫在膜生物反应器和活性污泥法中的污泥减量研究   总被引:10,自引:0,他引:10  
通过长达345d的中试规模试验,研究比较了蠕虫在膜生物反应器(MBR)和活性污泥法(CAS)的生长状况及其导致的污泥减量效果.CAS中的蠕虫生长状况明显优于MBR的蠕虫生长状况.MBR曝气池中平均蠕虫密度(10条·mg-1)远低于CAS曝气池中平均蠕虫密度(71条·mg-1),并且CAS中蠕虫连续保持高密度(>30条·mg-1)生长达172d.CAS中红斑瓢体虫和仙女虫交替成为优势蠕虫.蠕虫生长对MBR的污泥产率(0 40kg·kg-1)和污泥沉降性能(污泥沉降指数133mL·g-1)影响很小,但却能显著减少CAS的污泥产率(0 17kg·kg-1)和改善污泥沉降性能(污泥沉降指数为60mL·g-1).仙女虫比红斑瓢体虫能更大地减少污泥产量和更好地改善污泥沉降性能.蠕虫生长不影响MBR的COD去除率和出水水质,但却显著影响CAS的COD去除率和出水水质.  相似文献   

7.
京津冀国家干线公路污染空间特征分析   总被引:2,自引:0,他引:2  
李海萍  赵颖  傅毅明 《环境科学学报》2016,36(10):3515-3526
以国家干线公路交通量信息和单车排放因子为基础,基于GIS的路网线性参考系统,采用动态分段技术和核密度分析方法,从路段、污染物和车型这3个层次对2014年京津冀国家干线公路交通污染排放强度的空间差异进行分析.结果表明,车流量、车型构成和路网布局是引起排放强度空间分布差异的主要因素,排放强度高的路段集中在路网密度大且公路使用率高的京津地区,中小客车和特大货车对污染物排放强度影响显著.因使用燃料和车型的不同,NO_x、PM_(10)和PM_(2.5)排放强度分布大体一致,HC、CO空间分布更为相似.此外,经济发展水平、产业结构特征也是重要影响因素.北京除特大货车和集装箱以外的其他车型排放强度均很高,天津货车和客车排放强度均较高,河北货车排放强度高于客车.  相似文献   

8.
三峡水库蓄水初期鲤鱼重金属富集特征及健康风险评价   总被引:2,自引:0,他引:2  
于2011-2012年在三峡库区干流水域及7条典型支流中采集鲤鱼样品,通过测定鱼体肌肉组织中Cr、Cd、As、Pb、Ni、Cu和Zn等7种重金属含量,分析了三峡库区蓄水后的鱼体重金属污染水平、各金属元素之间的相关性及在库区各水域的分布特征,并利用目标危险系数(THQ)对库区居民通过食用鱼类摄入重金属的健康风险进行了评价.结果显示,所有鱼类样品中均检测出这7种重金属,但含量低于国家规定的卫生健康标准.不同重金属在鱼体肌肉中差异明显,Zn的平均含量最高(5.88 mg·kg-1),Cd平均含量最低(0.013 mg·kg-1).所有7种重金属可分为4类,式中,Cr和Cu,Pb和As相关系数较大.与库区外其他水域相比,三峡水库中鱼体重金属含量处于较低水平,且在蓄水后未发生显著变化.受到水位升高和悬浮物沉降的影响,库区内干流鱼体中大部分重金属含量变化趋势为从库尾的洛碛向库中的巫山递减.THQ法评价结果认为,食用库区鱼类健康风险较低.  相似文献   

9.
The bone-eating marine annelid Osedax consumes mainly whale bones on the deep-sea floor, but recent colonization experiments with cow bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax indicate that this worm might be able grow on a wider range of substrates. The suggested Cretaceous origin was thought to imply that Osedax could colonize marine reptile or fish bones, but there is currently no evidence that Osedax consumes bones other than those of mammals. We provide the first evidence that Osedax was, and most likely still is, able to consume non-mammalian bones, namely bird bones. Borings resembling those produced by living Osedax were found in bones of early Oligocene marine flightless diving birds (family Plotopteridae). The species that produced these boreholes had a branching filiform root that grew to a length of at least 3 mm, and lived in densities of up to 40 individuals per square centimeter. The inclusion of bird bones into the diet of Osedax has interesting implications for the recent suggestion of a Cretaceous origin of this worm because marine birds have existed continuously since the Cretaceous. Bird bones could have enabled this worm to survive times in the Earth’s history when large marine vertebrates other than fish were rare, specifically after the disappearance of large marine reptiles at the end-Cretaceous mass extinction event and before the rise of whales in the Eocene.  相似文献   

10.
本研究对广东一饮用水源保护区的河流氟喹诺酮类(Fluoroquinolones,FQs)抗生素进行分析.采用高效液相色谱法定性定量分析9个沉积物样品和5种鱼肉及1种鱼内脏中3种FQs—诺氟沙星(Norfloxacin,NOR)、环丙沙星(Ciprofloxacin,CIP)、恩诺沙星(Enrofloxacin,ENR)的残留特征,并与沉积物中有机质、总氮、总磷进行Person相关性分析.结果表明:河流沉积物各点平均值NORCIPENR,最大含量分别为:NOR248.25 ng·g-1,CIP 158.69 ng·g-1,ENR 56.81 ng·g-1;FQs和沉积物有机质、总磷相关系数平均为0.946、0.968(p0.01);5种鱼的鱼肉中FQs的含量可能高于或低于沉积物中FQs含量均值;鳙鱼内脏FQs含量是鱼肉中的3.21~9.53倍.研究结果对保障饮用水安全及水产品生态安全具有重要的意义.  相似文献   

11.
以鱼骨粉(FBM)为原料,利用NaOH处理制备高性能改性鱼骨粉材料(FBMT),通过比表面积仪(BET)、X射线衍射仪(XRD)、傅里叶红外光谱(FTIR)、扫描电镜-光电子能谱(SEM-EDS)、透射电镜(TEM)等手段对吸附前后材料形貌、孔结构、功能基团进行表征分析.结果表明,与FBM相比,FBMT出现一定数目中孔和大孔,具备了高孔容和平均孔径,分别增加68.57%和24.69%.FBMT材料表面-OH、C=O和PO43-等官能团含量增加,显示出一定的缓冲性能.FBM和FBMT对Cd(Ⅱ)的吸附经历快速的分配和慢速的吸附两个阶段,符合准二级动力学模型,相关系数R2分别达到0.8635及0.9480.Langmuir模型较好地拟合FBM和FBMT对Cd(Ⅱ)的等温吸附过程,对Cd(Ⅱ)饱和吸附量由改性前的9.28mg/g增至改性后的22.47mg/g,对应的吸附强度KF值也随之增加.分离因子0 < RL < 1表明Cd(Ⅱ)的去除过程为有利吸附.功能材料与Cd(Ⅱ)的作用机理主要包括阳离子专性吸附、静电吸附、离子交换、表面络合及沉淀作用.以上研究为鱼骨粉修复Cd污染提供一种经济有效的方法.  相似文献   

12.
Glycogen is a vital energy substrate for anaerobic organisms, and the size of glycogen stores can be a limiting factor for anoxia tolerance of animals. To this end, glycogen stores in 12 different tissues of the crucian carp (Carassius carassius L.), an anoxia-tolerant fish species, were examined. Glycogen content of different tissues was 2–10 times higher in winter (0.68–18.20% of tissue wet weight) than in summer (0.12–4.23%). In scale, bone and brain glycogen stores were strongly dependent on body mass (range between 0.6 and 785 g), small fish having significantly more glycogen than large fish (p < 0.05). In fin and skin, size dependence was evident in winter, but not in summer, while in other tissues (ventricle, atrium, intestine, liver, muscle, and spleen), no size dependence was found. The liver was much bigger in small than large fish (p < 0.001), and there was a prominent enlargement of the liver in winter irrespective of fish size. As a consequence, the whole body glycogen reserves, measured as a sum of glycogen from different tissues, varied from 6.1% of the body mass in the 1-g fish to 2.0% in the 800-g fish. Since anaerobic metabolic rate scales down with body size, the whole body glycogen reserves could provide energy for approximately 79 and 88 days of anoxia in small and large fish, respectively. There was, however, a drastic difference in tissue distribution of glycogen between large and small fish: in the small fish, the liver was the major glycogen store (68% of the stores), while in the large fish, the white myotomal muscle was the principal deposit of glycogen (57%). Since muscle glycogen is considered to be unavailable for blood glucose regulation, its usefulness in anoxia tolerance of the large crucian carp might be limited, although not excluded. Therefore, mobilization of muscle glycogen under anoxia needs to be rigorously tested.  相似文献   

13.
Effects of river water from the Yangtze River (Nanjing section) on fish development, vitellogenin (VTG) induction, gonado-somatic index (GSI) and sex ratio were investigated by exposing goldfish (Carassius auratus) in the early life stage (from fertilization to 28 days post-hatch) to water samples (25%, 50% and 100%) collected from three representative sections. The results showed that there was no significant effect on hatching success for any of the exposure groups, but survival was significantly reduced when compared with the control (P < 0.05). Body lengths, weights of all treated fish did not differ significantly from those of the control. Condition factors (CF) of larval fish exposed to 50% and 100% river water from the Jiangxinzhou section and 100% river water from the Daqiao section were significantly lower than that of the control (P< 0.05). VTG inductions were significant in larval fish exposed to all the dilution series of river water. No significant difference in CF value was observed in any exposure group after 150 days of depuration. VTG was fully eliminated after 75 days of depuration. For both female and male, GSI did not significantly differ between exposure groups and the control after 150 days of convalescence. The highest female:male ratios were observed in response to the treatment with 50% or 100% river water from the Jiangxinzhou section and 100% river water from the Daqiao section (53:47, 56:44 and 54:46, respectively), but no significant difference in sex ratio was observed in any treated group when compared to the control. The results showed that early life stage exposure of river water from the Yangtze River (Nanjing section) had adverse effects on goldfish development and reproductive health, and the effects on CF and VTG were reversible after depuration in clean water.  相似文献   

14.
基于SCGE的五氯酚对稀有鮈鲫DNA损伤的研究   总被引:3,自引:1,他引:2       下载免费PDF全文
采用单细胞凝胶电泳(SCGE)技术,研究了在不同的染毒时间内不同浓度的五氯酚(PCP)对稀有鮈鲫(Gobiocypris rarus)血细胞和肝脏细胞DNA的损伤.结果显示,各PCP染毒组细胞彗星尾部DNA含量 (%DNAT) 和彗星尾长(TL) 显著增加,与空白对照组比较,差异极显著(P0.926,说明在实验浓度范围内, 存在显著的浓度-效应关系.在同一浓度下,随着暴露时间的增加,处理组%DNAT和TL逐渐增加,存在显著的时间-效应关系.由于PCP可引起稀有鮈鲫血细胞和肝脏细胞DNA的严重损伤,因此稀有鮈鲫血细胞和肝脏细胞DNA的损伤可作为PCP遗传毒性的指示.  相似文献   

15.
Aspects of the trophic attributes of the mudskipper,Periophthalmus barbarus occurring in the mangrove swamps of ImoRiver estuary, Nigeria, were investigated during a 12-month period(April, 1992-March, 1993). Feeding intensity increased with size;it was higher in the dry season (November-April) than in the wetseason (May-October); monthly changes in the indices of feedingintensity were significantly correlated. Major food objectscomprised detritus and benthic algae; crustaceans, insects,macrophyte matter and sand grains were minor food objects whilefish, molluscs, Chilopoda, nematodes and fungi were unconsciouslydevoured objects. Diet varied seasonally; algae and sesarmid crabswere generally more in the dry season than during the rains whereasFPOM and fish increased in the wet over dry season. The mudskipperdisplay a high degree of euryphagy and can be considered as ageneralist and an omnivore. The lower trophic status of P. barbarusqualifies it as a good aquaculture candidate. Food richness washigher in big-sized class (BSC) than small-sized class (SSC).Size-based and seasonal variations were not apparent in foodrichness. Diet breadth was higher in the BSC than the SSC; therewas dry season increase in diet breadth.  相似文献   

16.
This paper deals with effects of airborne fluorine on the army worm, Mythimna separata (Walker), by rearing the larvae on the wheat foliage exposed to HF or fumigating the larvae on the artificial diet with the pollutant. Larval relative growth rate (GR) and index of population trend of the insect reduced by 5% and 11%, respectively, when the larvae were reared on the foliage taken from the wheat plants exposed to 0.87 g·dm-2·day-1 of fluorine compared with those of the control. An extra instar appeared in a majority of the larvae treated. Survival rate and GR of the larvae on the wheat plant being exposure to the same concentration of fluorine in field open-top fumigation device were 40% and 15% lower than that of the control, respectively. Similar experiment with the insect on the artificial diet also showed that direct impact of the pollutant on the army worm was greater than its indirect effect via their host plant.  相似文献   

17.
滦河流域鱼类群落结构空间异质性与影响因子分析   总被引:1,自引:0,他引:1       下载免费PDF全文
掌握鱼类群落结构与环境因子的关系是河流鱼类多样性保护与恢复的基础.基于2016年10月对滦河流域58个采样点的调查数据,通过聚类分析法及NMS(非度量多维标度法,non-matric multidimentionalscaling)分析了滦河鱼类群落空间格局特征,并采用典范对应分析(CCA,canonical correspondence analysis)探讨了影响鱼类群落结构的环境因子.调查期间共采集鱼类15科41属49种,鲤科鱼类最多,为23种.研究表明:①聚类分析发现鱼类空间分布可分为3组,第1组集中在滦河干流中下游及支流汇入干流附近河段,第2组集中在冀东部独流入海的河流,第3组集中在滦河干支流的中上游河段.②NMS结果也证明3组在空间分布上差异明显,第2组与第3组之间没有重叠.③物种数、Shannon-Wiener多样性指数、Margalef丰富度指数和Simpson多样性指数在第1组与第3组之间存在显著差异,而Simpson多样性在第2组与第3组之间也存在显著差异.④单因素方差分析(one-way ANOVA)显示,第1组与第2组、第3组相比,水温与两组之间都有显著性差异,第2组与第1组、第3组之间在电导率、TDS(总溶解固体)、栖境复杂性、速度-深度结合、堤岸稳定性和河水水量状况有显著性差异.⑤典范对应分析发现,影响滦河流域的环境因子包括TDS、浊度、pH与水温等4个水体理化参数以及底质与堤岸稳定性2个栖息地质量参数.研究显示,基于对滦河流域鱼类空间异质性和相关环境影响因子的理解,可为该流域鱼类多样性保护及管理对策制订提供方向.   相似文献   

18.
用~(14)C标记法研究呋喃丹在水稻-鱼和水稻-萍-鱼两种模拟生态系统中的分布、消失和残留行为。结果表明,由于萍的引入,使在水稻-萍-鱼系统中,田表水中的残留较低,而鱼体中残留较高。结合态残留物是土壤、鱼和植株体中呋喃丹的主要残留形态。  相似文献   

19.
Effects of SO2 pollution on growth of the army worm, Mythimna separata, were investigated by rearing the larvae for 12 days on the wheat plants being exposed to SO2 levels ranged from 50 to 200 ppb in the field open-top fumigation devices. Larval period shortened while their mean relative growth rate (MRGR) increased as SO2 dose elevated. Similar experiment with the insect on the artificial diet excluded the possibility that SO2 pollution directly stimulated growth of the army worm.The patterns of change in amino acid hydrolysates in the host foliage suggested that contents of methionine, and perhaps, arginine in food material exposed to unpolluted air were at such levels that they could only support sub-optimum growth of the insect, and SO2 pollution increased concentrations of these limiting amino acids, resulting in better performance of the larvae.  相似文献   

20.
Cooling water intake systems have the potential to adversely impact aquatic organisms though entrainment and impingement (impacts referenced under 316(b) of the Clean Water Act), yet the loss of individual fish does not necessarily mean that a population will suffer a significant decrease in number. The results of utility sponsored studies on Ohio River fish populations provide strong evidence of positive changes in the fishery due to water quality improvements. Despite these improvements, a simulation is needed to determine if a reduction in 316(b) fish losses would result in higher or similar fish population levels. Electrofishing data collected at seven power plant locations from 1981 to 1998 will be used for the population assessments. Potential 316(b) impacts on Ohio River fish populations will be modeled using site specific 316(b) data and a Leslie matrix model. The theoretical maximum population for various fish species, with and without 316(b) impacts, will be compared and the probabilistic risk that fish populations will fall below the threshold for species survival will be assessed. Historically, EPA has allowed 316(b) to be implemented on a case-by-case basis, however, the utilities believe that the first step in assessing potential adverse environmental impacts is to assess the condition of the affected fish populations.  相似文献   

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