Border irrigation is one of the most ancient but, at the same time, still widely applied irrigation methods across the world. Due to the intrinsic characteristics of the method, the water volumes involved are often difficult to measure and this implies a large uncertainty in the estimation of water use efficiency. In this study, we analyze the results of an extensive monitoring campaign, which was carried out over the agricultural season 2021 and was aimed at detecting the actual performance of border irrigation in different experimental fields located in the Padana plain (i.e. the largest irrigated plain in the EU). In particular, three maize fields characterized by different soil textures, irrigation scheduling and rainfall conditions were considered. The number of irrigation events, their duration, and the water amounts applied were examined and compared with the actual crop water requirements assessed by using the AquaCrop-OS agro-hydrological model. The performance of border irrigation, evaluated through a water use efficiency indicator, was assessed for the monitored agricultural season, as well as simulated over the last 28 years (1993–2020) to detect potential effects of different weather conditions. The main results show that the flow rate applied during each irrigation event ranges from 11 to 18 l s⁻¹ per unit width (m) of the irrigated strip, whereas the irrigation event duration varies between 80 and 130 min ha⁻¹ and substantially reflects the irrigation flow rate and the plot slope, the latter being variable between 2‰ and 7‰. The water use efficiency is highly dependent on the irrigation management, namely the flowrate and the scheduling of the irrigation events, with a minimum value of 16% and a maximum of 56%. The same range of efficiency was obtained for the last 28 years, mainly as a consequence of the application of a rigid irrigation scheduling determined by the rotation period. These findings provide useful information for improving the management of border irrigation in practice, and, more specifically, to understand what margin of improvement can be obtained in terms of water use efficiency, both under current conditions and in view of future increasing freshwater scarcity.

边境灌溉是最古老的灌溉方法之一，但与此同时，它仍然在世界范围内广泛应用。由于该方法的固有特性，所涉及的水量通常难以测量，这意味着在估计用水效率时存在很大的不确定性。在这项研究中，我们分析了在 2021 年农业季节开展的广泛监测活动的结果，旨在检测位于 Padana 平原（即印度最大的灌溉平原）不同试验田中边界灌溉的实际表现。欧盟）。特别是具有不同土壤质地、灌溉调度的三个玉米田。并考虑了降雨条件。检查灌溉事件的数量、持续时间和应用的水量，并与使用 AquaCrop-OS 农业水文模型评估的实际作物需水量进行比较。通过用水效率指标评估边界灌溉的性能，评估监测的农业季节，并在过去 28 年（1993-2020 年）进行模拟，以检测不同天气条件的潜在影响。主要结果表明，在每次灌溉事件期间应用的流量范围为每灌溉条带的单位宽度 (m)^-1-1并充分反映灌溉流量和地块坡度，后者在 2‰ 和 7‰ 之间变化。用水效率高度依赖于灌溉管理，即流量和灌溉事件的调度，最小值为 16%，最大值为 56%。在过去 28 年中获得了相同的效率范围，这主要是由于应用了由轮作周期确定的严格灌溉计划。这些发现为在实践中改善边境灌溉管理提供了有用的信息，更具体地说，可以了解在当前条件下和未来淡水日益稀缺的情况下，在用水效率方面可以获得多大的改进空间。