Li Qiang, Zhang Yuzhou, Wang Ruolan, Chu Ling, Li Yuru, Yan Yunzhi
Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, and School of Ecology and Environment Anhui Normal University Wuhu China.
College of Fisheries Ocean University of China Qingdao China.
Ecol Evol. 2022 Jul 30;12(8):e9156. doi: 10.1002/ece3.9156. eCollection 2022 Aug.
Extensive distribution of widespread species and the loss of native species driven by anthropogenic disturbances modify community similarity, resulting in a decrease or increase in community distinctiveness. Data from four basins in the Wannan Mountains, China, were used to evaluate the effects of low-head dams on patterns of fish faunal homogenization and differentiation based on abundance data. We aimed to examine the spatial changes in taxonomic and functional similarities of fish assemblages driven by low-head dams and to examine whether the changes in the similarity of fish assemblages differed between taxonomic and functional components. We found that low-head dams significantly decreased the mean taxonomic similarity but increased the mean functional similarity of fish assemblages in impoundments using abundance-based approaches, suggesting that taxonomic differentiation accompanied functional homogenization in stream fish assemblages. These results show the importance of population abundance in structuring fish faunal homogenization and differentiation at small scales, especially when the major differences among assemblages are in species abundance ranks rather than species identities. Additionally, we also found only a weak positive correlation between changes in mean taxonomic and functional similarities, and partial pairs exhibited considerable variation in patterns of fish faunal homogenization and differentiation for taxonomic and functional components. In conclusion, this study highlighted that the observed taxonomic differentiation of current fish assemblages (short-term phenomenon) is probably an early warning sign of further homogenization in regions where native species are completely predominated and that changes in taxonomic similarity cannot be used to predict changes in functional similarity.
广泛分布的常见物种以及由人为干扰导致的本地物种丧失会改变群落相似性，从而导致群落独特性降低或增加。基于丰度数据，利用中国皖南山区四个流域的数据来评估低水头水坝对鱼类区系同质化和分化模式的影响。我们旨在研究低水头水坝驱动下鱼类群落分类学和功能相似性的空间变化，并研究鱼类群落相似性的变化在分类学和功能组成部分之间是否存在差异。我们发现，采用基于丰度的方法，低水头水坝显著降低了水库中鱼类群落的平均分类学相似性，但提高了其平均功能相似性，这表明溪流鱼类群落中分类学分化伴随着功能同质化。这些结果表明了种群丰度在小尺度上构建鱼类区系同质化和分化中的重要性，特别是当群落之间的主要差异在于物种丰度等级而非物种身份时。此外，我们还发现平均分类学相似性和功能相似性的变化之间仅存在微弱的正相关，部分配对在鱼类区系同质化和分化模式的分类学和功能组成部分方面表现出相当大的差异。总之，本研究强调，当前鱼类群落观察到的分类学分化（短期现象）可能是在本地物种完全占主导地位的地区进一步同质化的早期预警信号，并且分类学相似性的变化不能用于预测功能相似性的变化。
