Department of Functional and Evolutionary Ecology, University of Vienna, 1090 Vienna, Austria.
Wassercluster Lunz-Biologische Station GmbH, 3293 Lunz am See, Austria.
Environ Sci Technol. 2020 Aug 18;54(16):10039-10048. doi: 10.1021/acs.est.0c02259. Epub 2020 Aug 4.
Streams and rivers metabolize dissolved organic matter (DOM). Although most DOM compounds originate from natural sources, recreational use of rivers increasingly introduces chemically distinct anthropogenic DOM. So far, the ecological impact of this DOM source is not well understood. Here, we show that a large music festival held adjacent to the Traisen River in Austria increased the river's dissolved organic carbon (DOC) concentration from 1.6 to 2.1 mg L and stream ecosystem respiration from -3.2 to -4.5 mg L. The DOC increase was not detected by sensors continuously logging absorbance spectra, thereby challenging their applicability for monitoring. However, the fluorescence intensity doubled during the festival. Using parallel factor analysis, we were able to assign the increase in fluorescence intensity to the chemically stable UV-B filter phenylbenzimidazole sulfonic acid, indicating organic compounds in sunscreen and other personal care products as sources of elevated DOC. This observation was confirmed by liquid chromatography coupled with mass spectrometry. The elevated respiration is probably fueled by anthropogenic DOM contained in beer and/or urine. We conclude that intense recreational use of running waters transiently increases the anthropogenic DOM load into stream ecosystems and alters the fluvial metabolism. We further propose that chemically distinct, manmade DOM extends the natural range of DOM decomposition rates in fluvial ecosystems.
河流和溪流代谢溶解的有机物质 (DOM)。尽管大多数 DOM 化合物来自自然来源，但河流的娱乐用途越来越多地引入了化学性质截然不同的人为 DOM。到目前为止，这种 DOM 来源的生态影响还不是很清楚。在这里，我们表明，在奥地利的特赖森河旁边举行的一个大型音乐节使河流的溶解有机碳 (DOC) 浓度从 1.6 毫克/升增加到 2.1 毫克/升，使溪流生态系统呼吸从 -3.2 毫克/升增加到 -4.5 毫克/升。连续记录吸收光谱的传感器没有检测到这种 DOC 增加，这对其监测的适用性提出了挑战。然而，荧光强度在节日期间增加了一倍。通过平行因子分析，我们能够将荧光强度的增加归因于化学稳定的 UV-B 过滤器苯并咪唑磺酸，表明防晒霜和其他个人护理产品中的有机化合物是升高的 DOC 的来源。液质联用进一步证实了这一观察结果。呼吸作用的增加可能是由啤酒和/或尿液中的人为 DOM 所驱动的。我们得出的结论是，高强度的娱乐性使用流水会暂时增加人为 DOM 对溪流生态系统的负荷，并改变河流的新陈代谢。我们进一步提出，化学性质独特的人造 DOM 扩展了河流生态系统中 DOM 分解率的自然范围。
