Naphthalene biodegradation in temperate and arctic marine microcosms
Naphthalene biodegradation in temperate and arctic marine microcosms
复制标题
DOI：
10.1007/s10532-013-9644-3
复制
发表时间：
2014-02-01
期刊：
影响因子：
3.6
通讯作者：
Kommedal, Roald
中科院分区：
文献类型：
--
作者：
Bagi, Andrea;Pampanin, Daniela M.;Kommedal, Roald
萘是最小的多环芳烃(PAH)，在原油中含量丰富，是海洋环境中的主要来源。多环芳烃的去除是通过生物降解进行的，这是决定它们在海洋中命运的关键过程。充分估计多环芳烃的生物降解率对于使用诸如漏油应急和反应(OSCAR)模型等数值模型进行环境风险评估和应对规划至关重要。以萘为模型化合物，对北海和北冰洋两个气候不同地区海水的生物降解速率、温度响应和细菌群落组成进行了研究和比较。在萘降解之后，使用OxiTop(A(R))系统测量封闭瓶子中的氧气消耗。采用聚合酶链式反应-变性梯度凝胶电泳法(PCR-DGGE)和焦磷酸测序分析了未处理和暴露于萘的样品中的微生物群落。在所有孵化温度下，北极海水样品中的萘降解速率系数比温带海水样品中的高三倍。然而，现场温度下的速率系数相似(温带为0.048天(-1)，北极为0.068天(-1))。在这两个海水中，萘的生物降解率以相似的Q(10)比(3.3和3.5)下降。利用OSCAR模型中实现的温度补偿方法，Q(10)=2，从测得的温度k(1)值计算，低估了北极海水的生物降解率，表明单独的温差不能很好地预测生物降解率。焦磷酸测序显示，温带和北极未经处理的海水群落是不同的。海水的地理来源影响暴露样品的群落组成。
Naphthalene, the smallest polycyclic aromatic hydrocarbon (PAH), is found in abundance in crude oil, its major source in marine environments. PAH removal occurs via biodegradation, a key process determining their fate in the sea. Adequate estimation of PAH biodegradation rates is essential for environmental risk assessment and response planning using numerical models such as the oil spill contingency and response (OSCAR) model. Using naphthalene as a model compound, biodegradation rate, temperature response and bacterial community composition of seawaters from two climatically different areas (North Sea and Arctic Ocean) were studied and compared. Naphthalene degradation was followed by measuring oxygen consumption in closed bottles using the OxiTop(A (R)) system. Microbial communities of untreated and naphthalene exposed samples were analysed by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and pyrosequencing. Three times higher naphthalene degradation rate coefficients were observed in arctic seawater samples compared to temperate, at all incubation temperatures. Rate coefficients at in situ temperatures were however, similar (0.048 day(-1) for temperate and 0.068 day(-1) for arctic). Naphthalene biodegradation rates decreased with similar Q(10) ratios (3.3 and 3.5) in both seawaters. Using the temperature compensation method implemented in the OSCAR model, Q(10) = 2, biodegradation in arctic seawater was underestimated when calculated from the measured temperate k(1) value, showing that temperature difference alone could not predict biodegradation rates adequately. Temperate and arctic untreated seawater communities were different as revealed by pyrosequencing. Geographic origin of seawater affected the community composition of exposed samples.