Departamento de Ingeniería Agronómica, Universidad Politécnica de Cartagena, Paseo Alfonso XIII, 48, 30230 Cartagena, Spain.
Departamento de Ingeniería Minera y Civil, Universidad Politécnica de Cartagena, Paseo Alfonso XIII, 52, 30230 Cartagena, Spain.
Sensors (Basel). 2022 Feb 10;22(4):1365. doi: 10.3390/s22041365.
Water scarcity in arid and semiarid regions poses problems for agricultural systems, awakening special interest in the development of deficit irrigation strategies to improve water conservation. Toward this purpose, farmers and technicians must monitor soil water and soluble nutrient contents in real time using simple, rapid and economical techniques through time and space. Thus, this study aimed to achieve the following: (i) create a model that predicts water and soluble nutrient contents in soil profiles using electrical resistivity tomography (ERT); and (ii) apply the model to different woody crops under different irrigation regimes (full irrigation and regulated deficit irrigation (RDI)) to assess the efficiency of the model. Simple nonlinear regression analysis was carried out on water content and on different ion contents using electrical resistivity data as the dependent variable. A predictive model for soil water content was calibrated and validated with the datasets based on exponential decay of a three-parameter equation. Nonetheless, no accurate model was achieved to predict any soluble nutrient. Electrical resistivity images were replaced by soil water images after application of the predictive model for all studied crops. They showed that under RDI situations, soil profiles became drier at depth while plant roots seemed to uptake more water, contributing to reductions in soil water content by the creation of desiccation bulbs. Therefore, the use of ERT combined with application of the validated predictive model could be a sustainable strategy to monitor soil water evolution in soil profiles under irrigated fields, facilitating land irrigation management.
在干旱和半干旱地区，水资源短缺给农业系统带来了问题，这引起了人们对开发亏缺灌溉策略以提高水的保有量的特别关注。为此，农民和技术人员必须通过时间和空间利用简单、快速和经济的技术实时监测土壤水分和可溶性养分含量。因此，本研究旨在实现以下目标：（i）创建一个使用电阻率层析成像（ERT）预测土壤剖面中水分和可溶性养分含量的模型；（ii）将该模型应用于不同灌溉制度（充分灌溉和调节亏缺灌溉（RDI））下的不同木本作物，以评估模型的效率。使用电阻率数据作为因变量，对水分含量和不同离子含量进行简单的非线性回归分析。采用三参数指数衰减方程对土壤水分预测模型进行了标定和验证。然而，没有建立准确的模型来预测任何可溶性养分。在对所有研究作物应用预测模型后，将电阻率图像替换为土壤水分图像。结果表明，在 RDI 情况下，土壤剖面在深度上变得更加干燥，而植物根系似乎吸收了更多的水分，通过形成干燥球导致土壤水分含量减少。因此，ERT 与验证后的预测模型的应用相结合，可以成为监测灌溉农田土壤剖面中土壤水分演变的可持续策略，从而促进土地灌溉管理。
