Department of Marine Ecology, University of Gothenburg, Gothenburg, Sweden.
Environ Microbiol. 2011 Oct;13(10):2738-51. doi: 10.1111/j.1462-2920.2011.02545.x. Epub 2011 Sep 5.
Vibrio abundance generally displays seasonal patterns. In temperate coastal areas, temperature and salinity influence Vibrio growth, whereas in tropical areas this pattern is not obvious. The present study assessed the dynamics of Vibrio in the Arabian Sea, 1-2 km off Mangalore on the south-west coast of India, during temporally separated periods. The two sampling periods were signified by oligotrophic conditions, and stable temperatures and salinity. Vibrio abundance was estimated by culture-independent techniques in relation to phytoplankton community composition and environmental variables. The results showed that the Vibrio density during December 2007 was 10- to 100-fold higher compared with the February-March 2008 period. High Vibrio abundance in December coincided with a diatom-dominated phytoplankton assemblage. A partial least squares (PLS) regression model indicated that diatom biomass was the primary predictor variable. Low nutrient levels suggested high water column turnover rate, which bacteria compensated for by using organic molecules leaking from phytoplankton. The abundance of potential Vibrio predators was low during both sampling periods; therefore it is suggested that resource supply from primary producers is more important than top-down control by predators.
弧菌丰度通常呈现季节性模式。在温带沿海地区，温度和盐度影响弧菌的生长，而在热带地区，这种模式并不明显。本研究评估了印度西南海岸芒格洛尔附近 1-2 公里处阿拉伯海的弧菌动态，该地区在时间上分为两个分离的时期。两个采样时期的特征是贫营养条件、稳定的温度和盐度。通过与浮游植物群落组成和环境变量相关的非培养技术来估计弧菌丰度。结果表明，2007 年 12 月的弧菌密度比 2008 年 2 月至 3 月期间高 10-100 倍。12 月弧菌的高丰度与硅藻为主的浮游植物组合一致。偏最小二乘（PLS）回归模型表明，硅藻生物量是主要的预测变量。低营养水平表明水柱周转率高，细菌通过利用从浮游植物中泄漏的有机分子来补偿。两个采样期间潜在弧菌捕食者的丰度都较低；因此，建议从初级生产者那里获得的资源供应比捕食者的自上而下控制更为重要。
