Derx Julia, Demeter Katalin, Linke Rita, Cervero-Aragó Sílvia, Lindner Gerhard, Stalder Gabrielle, Schijven Jack, Sommer Regina, Walochnik Julia, Kirschner Alexander K T, Komma Jürgen, Blaschke Alfred P, Farnleitner Andreas H
Institute of Hydraulic Engineering and Water Resources Management, TU Wien, Vienna, Austria..
Research Group Environmental Microbiology and Molecular Diagnostics E166/5/3, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Vienna, Austria.
Front Microbiol. 2021 Jul 14;12:668778. doi: 10.3389/fmicb.2021.668778. eCollection 2021.
Riverine wetlands are important natural habitats and contain valuable drinking water resources. The transport of human- and animal-associated fecal pathogens into the surface water bodies poses potential risks to water safety. The aim of this study was to develop a new integrative modeling approach supported by microbial source tracking (MST) markers for quantifying the transport pathways of two important reference pathogens, and , from external (allochthonous) and internal (autochthonous) fecal sources in riverine wetlands considering safe drinking water production. The probabilistic-deterministic model QMRAcatch (v 1.1 python backwater) was modified and extended to account for short-time variations in flow and microbial transport at hourly time steps. As input to the model, we determined the discharge rates, volumes and inundated areas of the backwater channel based on 2-D hydrodynamic flow simulations. To test if we considered all relevant fecal pollution sources and transport pathways, we validated QMRAcatch using measured concentrations of human, ruminant, pig and bird associated MST markers as well as in a Danube wetland area from 2010 to 2015. For the model validation, we obtained MST marker decay rates in water from the literature, adjusted them within confidence limits, and simulated the MST marker concentrations in the backwater channel, resulting in mean absolute errors of < 0.7 log particles/L (Kruskal-Wallis > 0.05). In the scenarios, we investigated (i) the impact of river discharges into the backwater channel (allochthonous sources), (ii) the resuspension of pathogens from animal fecal deposits in inundated areas, and (iii) the pathogen release from animal fecal deposits after rainfall (autochthonous sources). Autochthonous and allochthonous human and animal sources resulted in mean loads and concentrations of and (oo)cysts in the backwater channel of 3-13 × 10 particles/hour and 0.4-1.2 particles/L during floods and rainfall events, and in required pathogen treatment reductions to achieve safe drinking water of 5.0-6.2 log. The integrative modeling approach supports the sustainable and proactive drinking water safety management of alluvial backwater areas.
河流湿地是重要的自然栖息地，蕴藏着宝贵的饮用水资源。人类和动物相关粪便病原体进入地表水体对水安全构成潜在风险。本研究的目的是开发一种新的综合建模方法，该方法由微生物源追踪（MST）标记支持，用于量化两种重要参考病原体从河流湿地外部（外源）和内部（内源）粪便源的传输途径，同时考虑安全饮用水生产。对概率 - 确定性模型QMRAcatch（v 1.1 python回水）进行了修改和扩展，以考虑每小时时间步长内流量和微生物传输的短期变化。作为模型输入，我们基于二维水动力流模拟确定了回水河道的排放速率、体积和淹没面积。为了测试我们是否考虑了所有相关的粪便污染源和传输途径，我们使用2010年至2015年多瑙河湿地地区人类、反刍动物、猪和鸟类相关MST标记以及的测量浓度对QMRAcatch进行了验证。为了进行模型验证，我们从文献中获取了水中MST标记的衰减率，在置信区间内对其进行调整，并模拟了回水河道中的MST标记浓度，平均绝对误差<0.7 log颗粒/升（Kruskal - Wallis>0.05）。在这些情景中，我们研究了（i）河流排放到回水河道（外源）的影响，（ii）淹没区域动物粪便沉积物中病原体的再悬浮，以及（iii）降雨后动物粪便沉积物中病原体的释放（内源）。内源和外源的人类和动物源在洪水和降雨事件期间导致回水河道中（oo）囊的平均负荷和浓度为3 - 13×10颗粒/小时和0.4 - 1.2颗粒/升，以及为实现安全饮用水所需的病原体处理减少量为5.0 - 6.2 log。这种综合建模方法支持冲积回水区域的可持续和主动饮用水安全管理。
