Zhang Yong, Qu Zhishuai, Zhang Kexin, Li Jiqiu, Lin Xiaofeng
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Fujian Province Key Laboratory for Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, Xiamen 361102, China.
School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao 266071, China.
Microorganisms. 2024 Jan 8;12(1):124. doi: 10.3390/microorganisms12010124.
The relative role of stochasticity versus determinism is critically dependent on the spatial scale over which communities are studied. However, only a few studies have attempted to reveal how spatial scales influence the balance of different assembly processes. In this study, we investigated the latitudinal spatial scale dependences in assembly processes of microeukaryotic communities in surface water and sediment along the continental shelves of China. It was hypothesized that different microeukaryotic trophic groups (i.e., autotroph, heterotroph, mixotroph, and parasite) showed different latitudinal scale dependences in their assembly processes. Our results disclosed that the relative importance of different assembly processes depended on a latitudinal space scale for planktonic microeukaryotes. In surface water, as latitudinal difference increased, the relative contributions of homogenous selection and homogenizing dispersal decreased for the entire community, while those of heterogeneous selection and drift increased. The planktonic autotrophic and heterotrophic groups shifted from stochasticity-dominated processes to heterogeneous selection as latitudinal differences surpassed thresholds of 8° and 16°, respectively. For mixotrophic and parasitic groups, however, the assembly processes were always dominated by drift across different spatial scales. The balance of different assembly processes for the autotrophic group was mainly driven by temperature, whereas that of the heterotrophic group was driven by salinity and geographical distance. In sediment, neither the entire microeukaryotic community nor the four trophic groups showed remarkable spatial scale dependences in assembly processes; they were always overwhelmingly dominated by the drift. This work provides a deeper understanding of the distribution mechanisms of microeukaryotes along the continental shelves of China from the perspective of trophic groups.
随机性与确定性的相对作用严重依赖于研究群落的空间尺度。然而，只有少数研究试图揭示空间尺度如何影响不同组装过程的平衡。在本研究中，我们调查了中国陆架地表水和沉积物中微型真核生物群落组装过程中的纬度空间尺度依赖性。我们假设不同的微型真核生物营养类群（即自养生物、异养生物、混合营养生物和寄生虫）在其组装过程中表现出不同的纬度尺度依赖性。我们的结果表明，不同组装过程的相对重要性取决于浮游微型真核生物的纬度空间尺度。在地表水中，随着纬度差异的增加，整个群落的同质选择和同质化扩散的相对贡献降低，而异质选择和漂变的相对贡献增加。浮游自养和异养类群在纬度差异分别超过8°和16°的阈值时，从随机性主导的过程转变为异质选择。然而，对于混合营养和寄生类群，组装过程在不同空间尺度上始终由漂变主导。自养类群不同组装过程的平衡主要由温度驱动，而异养类群的平衡则由盐度和地理距离驱动。在沉积物中，整个微型真核生物群落和四个营养类群在组装过程中均未表现出明显的空间尺度依赖性；它们始终以漂变为主导。这项工作从营养类群的角度为深入理解中国陆架微型真核生物的分布机制提供了帮助。
