The metabolic and fitness costs associated with metal resistance in Nereis diversicolor     

Chris Pook  Ceri Lewis  Tamara Galloway 《Marine pollution bulletin》2009,58(7):1063-1071

The population of Nereis diversicolor inhabiting the upper reaches of Restronguet Creek, Cornwall, UK is highly resistant to acute zinc and copper toxicity. Here we employ bioenergetic accounting and fecundity counts to demonstrate the energetic costs associated with this phenomenon in terms of the worms’ allocation of metabolic resources and reproductive output [P_r]. Metal-resistant animals exhibited a scope for growth that was 46-62% less than that of animals from two non-resistant reference populations, corresponding to a mean metabolic cost of 1.31 mJ h⁻¹ mg DW⁻¹. The resistant population also contained 13% less lipid than animals from the reference populations and 73-81% less carbohydrates. Consequently, mass-specific fecundity was reduced in resistant animals by 39-45%, although material investment in individual gametes did not appear to vary. This demonstrates fitness costs associated with metal resistance in this ecologically important polychaete and adds to our understanding of phenotypic trade-offs associated with resistance.  相似文献   

Protective effects of chitosan against the hazardous effects of zinc oxide nanoparticle in freshwater crustaceans Ceriodaphnia cornuta and Moina micrura     

《Limnologica》2016

Nanoparticle contamination in freshwater habitat leads to the drastic reduction in the population of freshwater micro crustaceans. Both Ceriodaphnia cornuta and Moina micrura were considered as the potential biological bio-tracers of freshwater ecosystem. This study describes the chemical synthesis of zinc oxide nanoparticles (ZnO NPs) using zinc nitrate as the starting material. The physico-chemical characterization of ZnO NPs was made by UV–Vis spectroscopy, X-Ray Diffraction (XRD), Fourier Transform Infra Red (FTIR) and Transmission Electron Microscopy (TEM). ZnO NPs elicited 100% and 76% mortality of freshwater crustaceans, Ceriodaphnia cornuta and Moina micrura at 160 μg L⁻¹ respectively. The accumulation of ZnO NPs in the intestine and loss of antennae and carapace were clearly visualized through light microscopy. The exposure of C. cornuta and M. micrura neonates at 160 μg L⁻¹ of ZnO NPs showed abnormal swimming behaviour after 12 h. However, chitosan significantly reduced the mortality and enhanced the survival of C. cornuta and M. micrura at 100 μg ml⁻¹. This study concludes the protective effect of chitosan against the hazardous effect of ZnO NPs in C. cornuta and M. micrura.  相似文献   

Profiling Olive Oil Mill Wastewater by Resin Fractionation: Effect of Acid Cracking,Coagulation, Electrocoagulation,and Fenton's Reagent          下载免费PDF全文

Betul Hande Gursoy‐Haksevenler  Idil Arslan‐Alaton 《洁净——土壤、空气、水》2014,42(10):1384-1392

  相似文献   

砷的地球化学特征与研究方向   总被引：2，自引：1，他引：1  

伯英  罗立强 《岩矿测试》2009,28(6):569-575

砷的毒性在古代就因砒霜而广为人知,国际癌症研究会将砷列为第一类致癌物。目前,世界上有数以百万计的人受到砷中毒的威胁,砷污染事件在世界范围都有报道。环境中的砷的来源很复杂,有自然因素引起的砷污染(主要是地质成因砷污染),也有人为活动带来的砷污染,还有二者共同作用形成的砷污染。此外,砷还可以通过各种自然的地球化学过程和生物过程进行迁移转化,直接或间接对人和动物等产生危害。文章从砷的来源与分布、砷的毒性和危害、砷的迁移转化、生物在砷循环中作用的新认识等方面进行论述,并针对目前国内外砷污染研究现状,提出在已有研究基础上,建议在河套地区进一步开展砷元素地球化学及人体健康关系研究。  相似文献   

四种常用药物对蒙古裸腹溞的毒性研究   总被引：3，自引：0，他引：3  

王广军  黄建华  任保振 《海洋湖沼通报》2002,(1):75-78

本文研究了孔雀石绿、硫酸铜、甲醛以及高锰酸钾对蒙古裸腹溞 96小时的急性毒性,结果表明:蒙古裸腹溞对四种药物的敏感性顺序为：硫酸铜>孔雀绿>高锰酸钾>甲醛。96小时的安全浓度分别为:0.00710-6,0.024210-6,0.4410-6,12.8310-6。  相似文献   

NaCl侵蚀环境下水泥固化铬污染土的强度及淋滤特性     

刘晶晶  查甫生  郝爱玲  张雪芹  崔可锐 《岩土力学》2015,36(10):2855-2861

日益严重的环境污染问题导致土壤中的重金属离子越来越多,这不仅使得土的工程性质受到影响,而且有害重金属离子的渗出也会威胁人类的健康。目前常采用水泥固化技术（S/S法）来处理重金属污染土。但当地下水中富含侵蚀性盐离子时,固化后的重金属污染土会受到影响,进而改变其强度及重金属离子的滤出特性。通过系统的室内试验,对水泥固化铬污染土在NaCl溶液浸泡后的强度特性及重金属离子的滤出特性进行了研究。试验结果表明,水泥固化铬污染土的无侧限抗压强度随NaCl溶液浓度的增加而减小,而随浸泡时间的增加呈先减小后增大的趋势,浸泡7 d时最小。毒性特征沥滤试验（TCLP）结果显示,浸出液中Cr3+浓度随NaCl浓度增加而增大,随浸泡时间增加而减小;而浸出液的pH值随NaCl浓度增加而减小,随着浸泡时间的增加呈先减小后增大的趋势,浸泡7 d时最小;浸出液的pH值在4.0～5.5范围内时,Cr3+滤出量随pH值增大而减小。  相似文献   

Use of exposure time and life expectancy in models for toxicity to aquatic organisms     

Connell D  Yu J 《Marine pollution bulletin》2008,57(6-12):245-249

The exposure time is a variable which is usually not incorporated into models for toxicity. However, with persistent organic pollutants (POPs) exhibiting a nonspecific mode of action and lipophilic properties this variable can be modeled by the usage of the internal concentrations as a measure of the toxicity with fish. The bioconcentration process with fish is a relatively well understood and predictable process which allows the calculation of the internal lethal concentration. When the exposure time is relatively short the critical internal lethal concentrations are relatively constant for the group of POPs whereaas the LC50 measured in the ambient water is quite variable. When the exposure time is relatively long, results on the measurement of the critical internal concentration with fish over different exposure times has demonstrated that the internal lethal concentration falls with increasing exposure times in a consistent and predictable manner. This reduction in life expectancy can be described in a model which can be used to estimate the critical internal concentration for any exposure time. It also provides information useful in assessing the risk to fish and potentially other species due to the occurrence of residues of POPs in natural aquatic systems. It is suggested that these relationships can be extended to other groups of organisms and chemicals.  相似文献   

Ecotoxicological evaluation of polycyclic aromatic hydrocarbons using marine invertebrate embryo–larval bioassays     

Juan Bellas  Liliana Saco-lvarez   scar Nieto  Ricardo Beiras 《Marine pollution bulletin》2008,57(6-12):493

The toxicity of polycyclic aromatic hydrocarbons (PAHs) was determined using mussel, sea-urchin and ascidian embryo–larval bioassays. Fluorescent light exposure enhanced phenanthrene, fluoranthene, pyrene and hydroxypyrene toxicity in comparison with dark conditions, but not naphthalene and fluorene toxicity. The toxicity of PAHs was inversely related to their K_OW values following QSAR models derived for baseline toxicity of general narcotics, whereas the obtained regression using toxicity data from photoactivated PAHs significantly departed from the general narcosis model. Also, the mixture toxicity of five PAHs to the larval growth of the sea-urchin was compared with predictions derived from the concentration addition concept, indicating less than additive effects. Finally, we compared our toxicity data with worst-case environmental concentrations in order to provide a preliminary estimate of the risk to the marine environment. Naphthalene, fluorene and pyrene are not considered to pose a risk to sea-urchin, mussel or ascidian larvae, whilst phenanthrene and fluoranthene may pose a risk for mussel and sea-urchin. Moreover, a higher risk for those species is expected when we consider the photoactivation of the PAHs.  相似文献   

南海原油和燃料油对仔虾和仔鱼的急性毒性试验     

贾晓平  林钦 《热带海洋学报》1998,(1)

测定了南海原油、0号柴油和20号柴油对斑节对虾Penaeusmonodon、日本对虾Penaeusjoponicus、刀额新对虾Metapenaeusensis3种仔虾和黄鳍鲷和Sparuslatus、黑鲷Sparusmacrocephalus、前鳞鲻MugilOphuyseni和七星鲈Lateolabraxjaponicus4种仔鱼的急性毒性。油类对仔虾和仔鱼的毒性大小顺序均为：0号柴油＞20号柴油＞南海原油。油类分散液的毒性大于其水溶性组分。在曝油的3种仔虾中,刀额新对虾对0号柴油和20号柴油的耐受力最弱,而日本对虾对南海原油最为敏感。曝油仔鱼对3种油类的耐受力顺序为：黄鳍绸＞黑鲷＞前鳞鲻,而七星鲈对0号柴油最为敏感。3种仔虾对油类的耐受力明显低于4种仔鱼。  相似文献   

久效磷对僧帽牡蛎(Ostrea cucullata)染色体毒性效应研究     

王梅林  郑家声  李永祺 《中国海洋大学学报(自然科学版)》1998,(1)

受试僧帽牡蛎（Ｏｓｔｒｅａｃｕｃｕｌａｔａ）暴露在含有久效磷农药的海水中养育７ｄ,取鳃用空气干燥法制片,观察数千个早中期、中期细胞分裂相末发现微核、染色体结构变异及其它染色体畸变现象。但随久效磷浓度的增加细胞分裂相明显减少。处理过程中投饵和换水的僧帽牡蛎的细胞分裂相明显高于不投饵、不换水;但投饵和换水的僧帽牡蛎随久效磷浓度的增加细胞分裂被抑制的比率又快于不投饵、不换水。经久效磷处理的各组僧帽牡蛎核型与对照组的核型均为２ｎ＝２０,２０ｍ,ＮＦ＝４０。研究结果指出：双壳类的僧帽牡蛎对久效磷农药的毒性不敏感,在所试浓度范围内,并不引起染色体损伤的遗传效应,但产生抑制鳃细胞分裂的效应  相似文献