School of Ecology and Environmental Science, Yunnan University, Kunming, 650091, Yunnan, China; Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, 650091, Yunnan, China; Department of Ecology, School of Life Sciences, Nanjing University, Nanjing, China.
School of Ecology and Environmental Science, Yunnan University, Kunming, 650091, Yunnan, China; Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, 650091, Yunnan, China.
J Hazard Mater. 2020 Mar 5;385:121625. doi: 10.1016/j.jhazmat.2019.121625. Epub 2019 Nov 6.
Despite recent advances in assessing lethal effects of antibiotics on freshwater organisms, little is known about their potential consequences on community composition and function, which are essential for assessing the ecological risk of these pollutants. Here, we investigated the impact of norfloxacin (NOR) on the short-term (≤ 6 days) dynamics of co-cultured Scenedesmusquadricauda-Chlorella vulgaris and Scenedesmusobliquus-C. vulgaris, and the long-term (≤ 70 days) dynamics of co-cultured S.obliquus-C. vulgaris in experiments with or without grazer Daphnia magna at sublethal antibiotic concentrations (0, 0.5, 2 and 8 mg L). NOR increased the relative abundance of Scenedesmus species in the absence of grazers but exerted opposite effects when Daphnia was present in both short- and long-term experiments due to reduced colony size. Meanwhile, increasing NOR concentrations led to quickly increased total algal density in the initial stage, followed by a sharp decline in the long-term experiment in the absence of grazers; when Daphnia was present, population fluctuations were even larger for both prey and predator species (e.g., grazer extinction at the highest concentration). Thus, NOR affected the outcome of species interactions and decreased temporal stability of plankton ecosystems, suggesting that antibiotics have more extensive impacts than presently recognized.
尽管最近在评估抗生素对淡水生物的致死效应方面取得了进展，但对于它们对群落组成和功能的潜在影响知之甚少，而群落组成和功能对于评估这些污染物的生态风险至关重要。在这里，我们研究了诺氟沙星（NOR）对共培养的斜生栅藻-普通小球藻和钝顶螺旋藻-普通小球藻短期（≤6 天）动态的影响，以及在亚致死抗生素浓度（0、0.5、2 和 8 mg/L）下有无食藻动物大型溞存在的共培养钝顶螺旋藻长期（≤70 天）动态的影响。在没有食藻动物的情况下，NOR 增加了斜生栅藻属物种的相对丰度，但当大型溞存在于短期和长期实验中时，NOR 会产生相反的效果，因为这会导致藻细胞团体积减小。同时，在没有食藻动物的情况下，NOR 浓度的增加会在初始阶段迅速增加总藻类密度，随后在长期实验中急剧下降；而当大型溞存在时，两种猎物和捕食者的种群波动甚至更大（例如，在最高浓度时食藻动物灭绝）。因此，NOR 影响了物种相互作用的结果，并降低了浮游生物生态系统的时间稳定性，这表明抗生素的影响比目前所认识的更为广泛。
