Abstract This study attempts to assess the consistency of various low-flow indices evaluated at 12 water stations in the Ljubljanica river catchment, Slovenia, which is due to its high diversity of hydrogeological properties recognized as a non-homogenous catchment. Daily discharge data were used in the study for evaluating low-flow statistics (baseflow index, discharges from flow duration curves, mean annual minimums), seasonal indices, and analysis of hydrograph recession curves. The indices were compared at each station and their values were interpreted in terms of the connection between surface water and groundwater as well as the extent of contribution of delayed sources to surface water. Although all low-flow statistics point to the same stations in terms of the greatest and the lowest contribution of water from groundwater, we identified inconsistencies at some water stations. The hydrograph recession analysis and seasonal indices support the conclusions drawn from low-flow statistics analysis, with the seasonality ratio lower than 1 at all stations, meaning that summer low-flow conditions prevail across the catchment. However, at the torrential stream Gradascica, an inconsistency was found with recession constants that could be attributed to the inappropriate choice of computational parameters. We assessed the overall consistency heat map visualisation. Although it shows consistency between low-flow indices, some variations demonstrate that in case of hydrologically and geologically heterogeneous catchments, an analysis of several low-flow indices is needed in order to obtain a holistic overview of low-flow conditions and to avoid bad decisions in water resources management due to inappropriate consideration of low-flow characteristics.

中文翻译：

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评估水文地质非均质流域低流量指数的一致性：以斯洛文尼亚卢布尔雅那河流域为例

摘要 本研究试图评估在斯洛文尼亚卢布尔雅那河流域的 12 个水站评估的各种低流量指数的一致性，这是由于其被认为是非均质流域的水文地质特性的高度多样性。研究中使用每日流量数据来评估低流量统计数据（基流指数、流量持续时间曲线的流量、年平均最小值）、季节性指数和水文过程线衰退曲线的分析。在每个站点对这些指数进行比较，并根据地表水和地下水之间的联系以及延迟源对地表水的贡献程度来解释它们的值。尽管所有低流量统计数据都指向相同的站点，即地下水对水的最大贡献和最低贡献，我们发现一些供水站存在不一致的情况。水位线衰退分析和季节性指数支持低流量统计分析得出的结论，所有站点的季节性比都低于1，这意味着整个流域都处于夏季低流量状态。然而，在暴雨流 Gradascica 中，发现衰退常数不一致，这可能是由于计算参数选择不当所致。我们评估了整体一致性热图可视化。虽然它显示了低流量指数之间的一致性，但一些变化表明，在水文和地质异质流域的情况下，