Water scarcity in the Mediterranean area has increased the number of intermittent rivers, whose flow ceases either occasionally or totally. Key elements to characterize their dynamics are water quality, hydrological, and ecological status, when wastewater effluents dominate flow. Regarding water quality, pharmaceuticals are major pollutants, and serve as indicators of wastewater presence. Intermittent rivers are biodiversity hotspots where their hydrological regime may suffer alterations associated with wastewater effluents, making them harder to characterize than perennial streams.This study aimed to integratively characterize intermittent rivers through chemical, ecological and hydrological status calculating respective indices in twenty Mediterranean intermittent wastewater-impacted rivers located in Spain, France, Italy, Algeria and Tunisia. Pharmaceuticals were used as indicators assessing their frequency of PNEC exceedance and detection; while two ecological indicators and one hydrological indicator were used to evaluate wastewater stress on catchments. All indicators displayed a noticeable decline from upper to lower parts of the rivers, proving the effect of anthropogenic stressors on the aquatic environment. The Tunisian catchment displayed the most compromised conditions across all indicators, and the Algerian site even though low concentrations were detected, five compounds exceeded PNEC thresholds. This highlights the need for increased dedication and the adoption of water pollution solutions.

中文翻译：

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利用化学、生态和水文指标表征地中海间歇性河流的人为影响


地中海地区的缺水增加了间歇性河流的数量，这些河流有时或完全停止流动。当废水排放占主导地位时，表征其动态的关键要素是水质、水文和生态状况。就水质而言，药物是主要污染物，可作为废水存在的指标。间歇性河流是生物多样性热点，其水文状况可能会受到与废水排放相关的改变，使其比常年河流更难表征。本研究旨在通过计算 20 条地中海间歇性废水的相应指数，通过化学、生态和水文状况来综合表征间歇性河流。受影响的河流位于西班牙、法国、意大利、阿尔及利亚和突尼斯。药品被用作评估其 PNEC 超标和检测频率的指标；两项生态指标和一项水文指标用于评估流域废水压力。各项指标均呈现从上游到下游明显下降的趋势，证明了人为应激源对水环境的影响。突尼斯流域的所有指标均表现出最差的状况，而阿尔及利亚站点尽管检测到浓度较低，但仍有 5 种化合物超出了 PNEC 阈值。这凸显了加大投入和采用水污染解决方案的必要性。