The National Field Station of Freshwater Ecosystem of Liangzi Lake, College of Life Science, Wuhan University, Wuhan 430072, PR China.
Water Pollution Ecology Laboratory, College of Life Sciences, Wuhan University, Wuhan 430072, PR China.
Sci Total Environ. 2024 Jul 1;932:173030. doi: 10.1016/j.scitotenv.2024.173030. Epub 2024 May 7.
Antibiotic pollution and biological invasion pose significant risks to freshwater biodiversity and ecosystem health. However, few studies have compared the ecological adaptability and ciprofloxacin (CIPR) degradation potential between alien and native macrophytes. We examined growth, physiological response, and CIPR accumulation, translocation and metabolic abilities of two alien plants (Eichhornia crassipes and Myriophyllum aquaticum) and one native submerged species (Vallisneria natans) exposed to CIPR at 0, 1 and 10 mg/L. We found that E. crassipes and M. aquaticum's growth were unaffected by CIPR while V. natans was significantly hindered under the 10 mg/L treatment. CIPR significantly decreased the maximal quantum yield of PSII, actual quantum yield of PSII and relative electron transfer rate in E. crassipes and V. natans but didn't impact these photosynthetic characteristics in M. aquaticum. All the plants can accumulate, translocate and metabolize CIPR. M. aquaticum and E. crassipes in the 10 mg/L treatment group showed greater CIPR accumulation potential than V. natans indicated by higher CIPR contents in their roots. The oxidative cleavage of the piperazine ring acts as a key pathway for these aquatic plants to metabolize CIPR and the metabolites mainly distributed in plant roots. M. aquaticum and E. crassipes showed a higher production of CIPR metabolites compared to V. natans, with M. aquaticum exhibiting the strongest CIPR metabolic ability, as indicated by the most extensive structural breakdown of CIPR and the largest number of potential metabolic pathways. Taken together, alien species outperformed the native species in ecological adaptability, CIPR accumulation and metabolic capacity. These findings may shed light on the successful invasion mechanisms of alien aquatic species under antibiotic pressure and highlight the potential ecological impacts of alien species, particularly M. aquaticum. Additionally, the interaction of antibiotic contamination and invasion might further challenge the native submerged macrophytes and pose greater risks to freshwater ecosystems.
抗生素污染和生物入侵对淡水生物多样性和生态系统健康构成重大风险。然而，很少有研究比较外来和本地大型植物在生态适应性和环丙沙星（CIPR）降解能力方面的差异。我们研究了暴露于 0、1 和 10 mg/L CIPR 下的两种外来植物（凤眼莲和金鱼藻）和一种本地沉水植物（苦草）的生长、生理响应以及 CIPR 积累、转运和代谢能力。结果表明，CIPR 对外来植物凤眼莲和金鱼藻的生长没有影响，而沉水植物苦草在 10 mg/L 处理下受到显著抑制。CIPR 显著降低了凤眼莲和苦草的 PSII 最大光量子产量、PSII 实际量子产量和相对电子传递率，但对金鱼藻的这些光合特性没有影响。所有植物都能积累、转运和代谢 CIPR。与苦草相比，10 mg/L 处理组的金鱼藻和凤眼莲具有更高的 CIPR 积累潜力，其根部的 CIPR 含量更高。哌嗪环的氧化裂解是这些水生植物代谢 CIPR 的关键途径，代谢产物主要分布在植物根部。与苦草相比，金鱼藻和凤眼莲产生的 CIPR 代谢物更多，其中金鱼藻表现出最强的 CIPR 代谢能力，CIPR 的结构断裂最广泛，潜在代谢途径最多。总之，外来物种在生态适应性、CIPR 积累和代谢能力方面优于本地物种。这些发现可能揭示了抗生素压力下外来水生物种成功入侵的机制，并强调了外来物种，特别是金鱼藻的潜在生态影响。此外，抗生素污染和入侵的相互作用可能进一步挑战本地沉水植物，对淡水生态系统构成更大的风险。
