Seasonal and depth-related dynamics of prokaryotes and viruses in surface and deep waters of the northwestern Mediterranean Sea
- 標題
- Seasonal and depth-related dynamics of prokaryotes and viruses in surface and deep waters of the northwestern Mediterranean Sea
- 作者
- Christian Winter, Marie-Emmanuelle Kerros, Markus G. Weinbauer
- 文件屬性
- 國外期刊
- 知識分類
- 基礎研究
- 出版年
- 2009
- 刊名
- Deep Sea Research Part I
- 關鍵字
- Bacteriophage; Virus; Prokaryote; Marine; Deep sea; Flow cytometry
- 點閱數
- 2489
摘要
The study site located in the northwestern Mediterranean Sea was visited nine times in 2005–2006 to collect water samples from the epi- (5 m), meso- (200, 600 m), and bathypelagic (1000, 2000 m) zone. Total abundance of prokaryotes and viruses was determined by flow cytometry (FCM). Prokaryotic abundance in the epi-, meso-, and bathypelagic varied between 0.9 and 15.9×105, 0.6 and 2.1×105, and 0.3 and 1.3×105 ml−1, respectively. Variation of viral abundance in the epi-, meso-, and bathypelagic was between 1.2 and 57.5×106, 0.5 and 3.5×106, and 0.4 and 1.3×106 ml−1, respectively. The fraction of low (LNA) and high (HNA) nucleic acid prokaryotes averaged 42.9% and 57.1% throughout the water column and did not differ between depth layers. Throughout the water column the fraction of low, medium, and high fluorescent viruses (Vir-LF, Vir-MF, Vir-HF) averaged 66.3%, 30.2%, and 3.5%. Vir-LF and Vir-MF did not differ between depth layers; however, Vir-HF showed a preference for surface waters. The fraction of LNA cells decreased in the epi- and increased in the bathypelagic with decreasing stratification. The fraction of Vir-LF viruses increased in the epipelagic and decreased in the bathypelagic with increasing prokaryotic abundance. Also, the relationship between viral abundance and the bacterial community was different in surface and deep waters. The data suggest that different mechanisms of interaction between viruses and their prokaryotic hosts prevail at the surface and in deep waters.