Asian Natural Environmental Science Centre, University of Tokyo, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Mar Pollut Bull. 2010 Feb;60(2):299-302. doi: 10.1016/j.marpolbul.2009.11.019. Epub 2009 Dec 21.
Ships carry ballast water for better stability and to control trim. However, the discharge of ballast water near ports is known to transport invasive species from one coastal area to another. The exchange of ballast water on the high seas is supposed to reduce such invasions of exotic species. In this study, we used denaturing gradient gel electrophoresis (DGGE) to analyze the composition of the bacterial community in ballast water before and after such a mid-ocean exchange, and we also measured total bacterial counts. Our findings confirmed that the ballast water was replaced by the mid-ocean exchange, as indicated by the marked change in the composition of the bacterial community. There was also a significant decrease in bacterial abundance after the mid-ocean exchange. Finally, our findings support the incubation hypothesis, because the composition of the bacterial communities changed over time within the same ballast water.
船舶携带压载水以提高稳定性和控制吃水。然而，在港口附近排放压载水已知会将入侵物种从一个沿海地区运输到另一个沿海地区。在公海上交换压载水应该可以减少这种外来物种的入侵。在这项研究中，我们使用变性梯度凝胶电泳 (DGGE) 分析了公海交换前后压载水中细菌群落的组成，并测量了总细菌计数。我们的研究结果证实，压载水确实被公海交换所取代，这从细菌群落组成的明显变化中可以看出。公海交换后，细菌丰度也显著下降。最后，我们的研究结果支持了孵育假说，因为在同一压载水中，细菌群落的组成随时间发生了变化。
