Departamento de Ingeniería Agroforestal. E.T.S.I. Agronómica, Alimentaria y Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
Irritecs.p.a., Via Gambitta Conforto, 98071 Capo D'Orlando, ME, Italy.
Sci Total Environ. 2022 Feb 1;806(Pt 1):150492. doi: 10.1016/j.scitotenv.2021.150492. Epub 2021 Sep 24.
Most perennial crops sensitive to water scarcity, such as citrus, can benefit from efficient water management, which allows for reduced water consumption while increasing crop production on a long-term basis. However, when implementing water-saving strategies, it is necessary to monitor soil and/or plant water status in order to determine crop water demand. A plethora of devices providing indirect measurements of volumetric soil water content, such as the "drill and drop" multi-sensors probes (Sentek, Inc., Stepney, Australia), have been developed over the last decade. The objective of the paper was to analyse time-series of soil water content profiles and meteorological data collected in an adult citrus orchard over three years of field observations (2017-2020) in order to estimate actual crop evapotranspiration and derive crop coefficients. Simultaneous measurements of sap fluxes also allowed for the estimation of the basal crop coefficient, K, used as a control variable. The temporal dynamics of soil water content profiles following rainfall or irrigation events provided information on soil evaporation, root water uptake, and actual crop transpiration. After soil wetting events, in particular, it was possible to recognize patterns of actual crop evapotranspiration similar to those detected with sap flow sensors. The knowledge of actual crop evapotranspiration at the daily time-step, in conjunction with the corresponding reference crop evapotranspiration, allowed for appropriate estimations of the crop coefficient associated with the various development stages. The proposed method provided interesting insights into the dynamics of root water uptake and crop evapotranspiration of the studied citrus orchard, and it represents a promising tool for precise irrigation scheduling in other agroecosystems.
大多数对缺水敏感的多年生作物，如柑橘类，都可以受益于高效的水资源管理，这可以在长期内减少水的消耗，同时增加作物产量。然而，在实施节水策略时，有必要监测土壤和/或植物的水分状况，以确定作物的水分需求。过去十年中，已经开发出了许多提供土壤体积含水量间接测量的设备，例如“钻取-滴落”多传感器探头（Sentek，Inc.，澳大利亚 Stepney）。本文的目的是分析在三年的田间观测（2017-2020 年）中收集的成年柑橘园的土壤水分剖面和气象数据的时间序列，以估算实际作物蒸散量并得出作物系数。同时测量 sap 通量也允许估算基础作物系数 K，用作控制变量。降雨或灌溉事件后土壤水分剖面的时间动态提供了有关土壤蒸发、根系吸水和实际作物蒸腾的信息。特别是在土壤湿润事件后，可以识别出与 sap 流传感器检测到的相似的实际作物蒸散模式。在每日时间步长上了解实际作物蒸散量，同时结合相应的参考作物蒸散量，可以对与各种发育阶段相关的作物系数进行适当估算。所提出的方法为研究柑橘园的根系吸水和作物蒸散动态提供了有趣的见解，并且它代表了在其他农业生态系统中进行精确灌溉调度的有前途的工具。
