Abstract：
Understanding microbial community structure and the underlying control mechanisms are fundamental purposes of aquatic ecology. However, little is known about the seasonality and how trophic conditions regulate plankton community in subtropical reservoirs. In this study, we study the prokaryotic and picoeukaryotic communities and their interactions during wet and dry seasons in two subtropical reservoirs: one at oligotrophic state and another at mesotrophic state. Distinct microbial community compositions (prokaryotes and picoeukaryotes) and seasonal variation pattern were detected in the oligotrophic and mesotrophic reservoirs. The interactions between prokaryotic and picoeukaryotic communities were more prevalent in the oligotrophic reservoir, suggesting enhanced top-down control of small eukaryotic grazers on the prokaryotic communities. On the other hand, the microbial community in the mesotrophic reservoir was more influenced by physico-chemical parameters and showed a stronger seasonal variation, which may be the result of distinct nutrient levels in wet and dry seasons, indicating the importance of bottom-up control. Our study contributes to new understandings of the environmental and biological processes that shape the structure and dynamics of the planktonic microbial communities in reservoirs of different trophic states.
摘要：
了解微生物群落结构和潜在的控制机制是水生生态学的基本目的。然而,关于季节性以及营养条件如何调节亚热带水库中的浮游生物群落知之甚少。在这项研究中,我们研究了两个亚热带水库在干湿季节的原核和皮真核生物群落及其相互作用：一个处于贫营养状态，另一个处于中营养状态。在贫营养和中营养水库中检测到不同的微生物群落组成（原核生物和真核生物）和季节变化模式。原核和皮真核生物群落之间的相互作用在贫营养储层中更为普遍，表明增强了对原核生物群落的小型真核放牧者的自上而下控制。另一方面,中营养油藏微生物群落受理化参数影响较大，季节变化较强，这可能是干湿季节营养水平不同的结果，表明自下而上控制的重要性。我们的研究有助于对环境和生物过程的新理解，这些过程塑造了不同营养状态水库中浮游微生物群落的结构和动力学。
