SPONTANEOUS ACCOMMODATION OF IRRIGATION SCHEDULING TO GROUNDWATER THROUGH FEEDBACK FROM SOIL WATER SENSORS IN DRIP IRRIGATED PEACH

J. Casadesús, M. Mata, J. Marsal, J. Girona
Automated scheduling of irrigation is required to give farmers the opportunity of applying efficient irrigation with little dependence on labour, skills and perseverance. Integration of sensor data in irrigation scheduling is desired to facilitate supervision and to provide some indication of irrigation fitness. We recently proposed an algorithm for automated irrigation scheduling of tree crops. This was based on combining a simple model for estimating the daily irrigation needs with a feedback mechanism that tunes the model in response to some irrigation fitness indicator derived from sensors in the soil or on the plant. In that algorithm, the feedback mechanism is intended to correct the model bias due either to the simplicity of the model, its inaccurate parameterization or to the omission of some term in water balance that under certain scenarios can be relevant. This is the case for groundwater, whose contribution in practice is very difficult to assess. Here, we present a trial where automated irrigation scheduling tuned by feedback from soil water sensors was applied during two irrigation seasons to a plot that received an unknown and variable input from groundwater. The scheduling algorithm spontaneously reduced the overall irrigation to one third of the estimated evapotranspiration while keeping the tree’s water status in a safe range. Furthermore, daily irrigation doses dynamically responded to changes in the contribution of groundwater during the season. This can be an example of how feedback from soil sensors can automatically be used to com¬pensate the site-specific bias in the estimation of irrigation requirements.
Casadesús, J., Mata, M., Marsal, J. and Girona, J. (2014). SPONTANEOUS ACCOMMODATION OF IRRIGATION SCHEDULING TO GROUNDWATER THROUGH FEEDBACK FROM SOIL WATER SENSORS IN DRIP IRRIGATED PEACH. Acta Hortic. 1038, 207-213
DOI: 10.17660/ActaHortic.2014.1038.24
https://doi.org/10.17660/ActaHortic.2014.1038.24
ETo, Kc, soil water content, localized irrigation
English

Acta Horticulturae