The characterization by means of geophysical techniques of agricultural soils subjected to continuous irrigation cycles makes it possible to study the heterogeneity of a soil and the preferential pathways of water flows without disturbing soil and plants. A better knowledge of soil heterogeneity enables optimal water resource management in terms of crop, yield, and sustainability. In this study, time-lapse monitoring using electrical resistivity tomographies (ERT) is proposed as a reliable and non-invasive technique to quantify the movement of water flows and thus the variation of soil water content during the irrigation process. ERT surveys have been conducted in melon-growing soils in southern Tuscany (Italy). Five survey campaigns have been carried out between June and August 2022, in which ERT data have been collected by taking measurements before (T₀), during (T₁), and after (T₂) the irrigation phase. The interpretation of the ERT results provided information on the spatial and temporal distribution of water fluxes in the soil and root zone of melons during the irrigation phases. The investigation made it possible to identify the preferential pathways of infiltration of irrigation water, the points where water is absorbed by the roots, and the points where water follows a preferential pathway instead distributing itself entirely below the root growth zone. Thus, this research suggests that the ERT technique can be used to evaluate the efficiency of the irrigation system in order to achieve optimal management of the water resource, avoiding preferential flow paths that lead to less water availability for the plant.

通过地球物理技术对经过连续灌溉循环的农业土壤进行表征，可以在不干扰土壤和植物的情况下研究土壤的异质性和水流的优先路径。更好地了解土壤异质性可以实现作物、产量和可持续性方面的最佳水资源管理。在这项研究中，提出使用电阻率层析成像（ERT）进行延时监测作为一种可靠的非侵入性技术，用于量化水流的运动，从而量化灌溉过程中土壤含水量的变化。ERT 调查已在托斯卡纳（意大利）南部的甜瓜种植土壤中进行。2022 年 6 月至 8 月期间开展了五次调查活动，其中通过在灌溉阶段之前 ( T ₀ )、期间 ( T ₁ ) 和之后 ( T _{2 ) 进行测量来收集 ERT 数据。}ERT 结果的解释提供了灌溉阶段土壤和瓜类根区水通量的空间和时间分布信息。这项调查使得确定灌溉水渗透的优先路径、根部吸收水的点以及水沿着优先路径而不是完全分布在根生长区下方的点成为可能。因此，本研究表明，ERT 技术可用于评估灌溉系统的效率，以实现水资源的优化管理，避免导致植物可用水量减少的优先流路。