College of Resources and Environment, Southwest University, Chongqing, 400715, China.
School of Biological Sciences, University of Western, Australia, Perth, WA, 6009, Australia.
Environ Sci Pollut Res Int. 2024 May;31(25):37705-37716. doi: 10.1007/s11356-024-33613-2. Epub 2024 May 23.
The hydrographic and environmental factors along the Three Gorges Reservoir (TGR) have been significantly altered since the Three Gorges Dam (TGD) began working in 2006. Here, we collected 54 water samples, and then measured the environmental factors, followed by sequencing of the 18S rRNA gene and subsequent analysis of community assembly mechanisms. The findings indicated that the majority of environmental variables (such as AN, TP, Chl-a, COD, and Cu) exhibited both temporal and spatial variations due to the influences of the TGD. The distribution of different environmental factors and microeukaryotic plankton communities is influenced by the changing seasons. The community structure in TGR showed variations across three seasons, possibly due to variations in their environmental preferences, inherent dissimilarities, and seasonal succession. Furthermore, different communities exhibited a comparable distance-decay trend, suggesting that distinct taxa are likely to exhibit a similar spatial distribution. In addition, the community formation in TGR was influenced by both deterministic and stochastic factors, with the balance between them being mainly controlled by the season. Specifically, deterministic processes could explain 33.9-51.1% of community variations, while stochastic processes could contribute 23.5-32.2%. The findings of this research demonstrated that the varying ecological processes' significance relied on environmental gradients, geographical scale, and ecological conditions. This could offer a fresh outlook on comprehending the composition, assembly mechanisms, and distribution patterns of microeukaryotic plankton in reservoir ecosystems.
自 2006 年三峡大坝开始运行以来，三峡水库的水文和环境因素发生了显著变化。在这里，我们收集了 54 个水样，然后测量了环境因素，接着对 18S rRNA 基因进行了测序，并对群落组装机制进行了后续分析。研究结果表明，由于三峡大坝的影响，大多数环境变量（如 AN、TP、Chl-a、COD 和 Cu）都表现出时间和空间的变化。不同环境因素和微型真核浮游生物群落的分布受到季节变化的影响。TGR 的群落结构在三个季节呈现出变化，可能是由于它们对环境的偏好、内在差异和季节性演替的变化。此外，不同的群落表现出相似的距离衰减趋势，表明不同的分类群可能表现出相似的空间分布。此外，TGR 的群落形成受到确定性和随机性因素的影响，它们之间的平衡主要由季节控制。具体来说，确定性过程可以解释群落变化的 33.9-51.1%，而随机性过程可以贡献 23.5-32.2%。本研究的结果表明，不断变化的生态过程的重要性取决于环境梯度、地理尺度和生态条件。这为理解水库生态系统中微型真核浮游生物的组成、组装机制和分布模式提供了新的视角。
