【作者】 宗虎民；

【导师】 马德毅； 王菊英；

【作者基本信息】 大连海事大学 ， 环境科学， 2008， 博士

【摘要】 水产养殖中使用的抗生素仅有小部分被鱼类吸收,大部分抗生素会进入水环境中。在杀灭有害病菌的同时,抗生素会对海洋生物和沉积环境产生影响,从而影响沉积物中生源要素的生物地球化学循环。本文选择在水产养殖中大量使用的氟苯尼考为研究对象,研究了其在海洋环境中的迁移转化规律,并从不同角度分析了氟苯尼考对沉积物生源要素生物地球化学循环的潜在影响。主要结果如下:建立了环境介质中氟苯尼考残留的HPLC和HPLC-MS/MS检测方法,检出限分别为40和0.01μg/L。初始浓度、温度、微生物的活性以及有机质的含量都会对氟苯尼考的降解产生影响。去除沉积物有机质前后氟苯尼考吸附系数变化不大,且随盐度、pH值、温度的升高而减小。高浓度氟苯尼考强烈抑制沉积物中细菌数量,随着氟苯尼考的降解影响变小。氟苯尼考不同程度上抑制了沉积物中的胞外酶活性、纤维分解作用、呼吸作用、(亚)硝化细菌和硫化细菌的生长,且改变了沉积物微生物群落构成。低浓度氟苯尼考对小球藻和菲律宾蛤仔的抗氧化酶活性具有诱导作用,高浓度则产生抑制作用。不同浓度氟苯尼考对菲律宾蛤仔体内的Na~+K~+-ATP酶活性和GR活性都有明显的抑制作用。较高浓度的氟苯尼考对小球藻生长、叶绿素的合成、蛋白质的增加有抑制作用。氟苯尼考可以导致生源要素在沉积物中出现不同程度的积累,且在沉积物纵深处影响更加明显,并对生源要素在沉积物—水界面的交换通量有明显的影响。氟苯尼考抑制了沉积物中氧化还原电位的变化和硫化物的转化。对大连近岸养殖氟苯尼考的残留调查显示,11个站位中有6个水样检测到氟苯尼考。使用过抗生素的沉积环境中微生物对氟苯尼考具有明显的抗药性,使用过抗生素,且检出了氟苯尼考的残留的区域沉积物中细菌的抗药性明显强于其它区域,且微生物多样性指数都明显低于未使用过任何抗生素的区域。更多还原

【Abstract】 A great part of unused antibacterials which were widely used in marine aquaculture farms all over the world will eventually enter the aquatic environment, it have the opportunities to affect the marine organism and depositional environment while killing pathogen, by which the biogeochemical cycling of material in marine sediment will be disturbed. The primary object of this research is to comprehensively evaluate environmental risk of florfenicol which is used frequently in aquaculture. The the environmental behavior of florfenicol and the environmental impacts of florfenicol in marine environment were studied. The main conclusions obtained are listed as follows:The analytical methods about residue determination of florfenicol in sea water and sediment by HPLC and LC-MS/MS were established. The detection limit of HPLC and LC-MS/MS method was 40 and 0.01μg/L, respectivly.The initial concentration, temperature, the activity of microorganism and the content of organic matter were all had influences on the degradation of florfenicol in the sediment. The adsorption coefficient was no obvious change after the removing organic matter from the sediment and it became lower with the increasing of ion strength, pH, and temperature.High concentration of florfenicol could apparently inhibit the density and activities of microorganism and the influence became slightly with the degradation of florfenicol. Florfenicol could inhibit the activities of extracellular enzyme, cellulosic decomposition, respiration, the growth of AOB, NOB and sulphur bacteria in sediment in different degree.The community diversity of microorganism in sediment was change under the pressure of florfenicol.Florfenicol at lower concentration could induce antioxidase activities of Chlorella vulgaris and Ruditapes philippinarum, but inhibition occurred at higher concentration. Florfenicol could inhibit the activities of Na~+K~+-ATP and GR obviously at different concentration. Florfenicol at higher concentration could aslo inhibit the growth, the formation of chlorophyl and protein of Chlorella vulgaris.5. Florfenicol will lead to accumulation of material in sediment and it became more obvious in deeper of the sediment. The influences of florfenicol on the diffusion fluxes of material at sediment-water interface were apparently. Furthermore, florfenicol could inhibit the variation of Eh and sulfides in the sediment.6. The investigation in aquaculture areas in Dalian coastal zone showed that six seawater samples have been detected florfenicol residues among eleven stations. The bacteria resistance to florfenicol in sediment had increased due to the use of antibiotics and the resistance of bacteria became stronger in the areas which have been detected florfenicol residues. Moreover, function diversity indexes of microorganism in sediment were lower than the areas where antibacterials were not uesd before.更多还原