Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, China.
Collaborative Innovation Center for Biodiversity and Conservation in the Three Parallel Rivers Region of China, Dali, Yunnan, China.
Sci Rep. 2023 Mar 6;13(1):3720. doi: 10.1038/s41598-023-30685-x.
As the most potential ecological "law", the mechanism of the species-area relationship (SAR) remains controversial. Essentially, the SAR addresses the relationship between regional area and biodiversity, shaped by speciation, extinction and dispersal processes. Extinction is the process of loss and a direct cause of species richness differences in community. Therefore, it is crucial to elucidate the role of extinction in shaping SAR. Since the extinction process has temporal dynamics, we propose the hypothesis that the occurrence of SAR should also have temporal dynamics. Here, we designed independent closed microcosm systems, in which dispersal/speciation can be excluded/neglected to reveal the role of extinction in shaping the temporal dynamics pattern of SAR. We find that extinction can shape SAR in this system independent of the dispersal and speciation process. Due to the temporal dynamics of the extinction, SAR was temporally discontinuous. The small-scale extinctions modified community structure to promote ecosystem stability and shaped SAR, while mass extinction pushed the microcosm system into the next successional stage and dismissed SAR. Our result suggested that SAR could serve as an indicator of ecosystem stability; moreover, temporal discontinuity can explain many controversies in SAR studies.
作为最具潜力的生态“法则”，种-面积关系（SAR）的机制仍然存在争议。本质上，SAR 探讨了区域面积和生物多样性之间的关系，由物种形成、灭绝和扩散过程塑造。灭绝是物种损失的过程，也是群落物种丰富度差异的直接原因。因此，阐明灭绝在塑造 SAR 中的作用至关重要。由于灭绝过程具有时间动态，我们提出假设，即 SAR 的发生也应该具有时间动态。在这里，我们设计了独立的封闭微宇宙系统，在该系统中可以排除/忽略扩散/物种形成，以揭示灭绝在塑造 SAR 时间动态模式中的作用。我们发现，在这个系统中，灭绝可以独立于扩散和物种形成过程来塑造 SAR。由于灭绝的时间动态，SAR 是时间上不连续的。小规模的灭绝改变了群落结构，促进了生态系统的稳定性，并塑造了 SAR，而大规模的灭绝则将微宇宙系统推向了下一个演替阶段，并取消了 SAR。我们的结果表明，SAR 可以作为生态系统稳定性的指标；此外，时间不连续性可以解释 SAR 研究中的许多争议。
