Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology, 261 Cheomdan-gwagiro, Buk-gu, Gwangju, 500-712, Korea.
J Environ Sci (China). 2010;22(6):846-50. doi: 10.1016/s1001-0742(09)60187-x.
Most probable number (MPN) and colony-forming unit (CFU) estimates of fecal indicator bacteria (FIB) concentration are common measures of water quality in aquatic environments. Thus, FIB intensively monitored in Yeongsan Watershed in an attempt to compare two different methods and to develop a statistical model to convert from CFU to MPN estimates or vice versa. As a result, the significant difference was found in the MPN and CFU estimates. The enumerated Escherichia coli concentrations in MPN are greater than those in CFU, except for the measurement in winter. Especially in fall, E. coli concentrations in MPN are one order of magnitude greater than that in CFU. Contrarily, enterococci bacteria in MPN are lower than those in CFU. However, in general, a strongly positive relationship are found between MPN and CFU estimates. Therefore, the statistical models were developed, and showed the reasonable converting FIB concentrations from CFU estimates to MPN estimates. We expect this study will provide preliminary information towards future research on whether different analysis methods may result in different water quality standard violation frequencies for the same water sample.
最可能数 (MPN) 和集落形成单位 (CFU) 估计值是水生环境中粪便指示菌 (FIB) 浓度的常用测量方法。因此，在研究中对延山流域的 FIB 进行了密集监测，旨在比较两种不同的方法，并开发一种统计模型，以便将 CFU 估计值转换为 MPN 估计值或反之亦然。结果表明，MPN 和 CFU 估计值存在显著差异。除冬季外，MPN 中大肠杆菌的计数浓度大于 CFU 中的浓度。特别是在秋季，MPN 中大肠杆菌的浓度比 CFU 中高一个数量级。相反，MPN 中的肠球菌浓度低于 CFU 中的浓度。然而，总体而言，MPN 和 CFU 估计值之间存在很强的正相关关系。因此，建立了统计模型，表明可以合理地将 FIB 浓度从 CFU 估计值转换为 MPN 估计值。我们希望本研究将为未来的研究提供初步信息，即对于同一水样，不同的分析方法是否可能导致不同的水质标准违规频率。
