ABSTRACT
Improving irrigation efficiency can contribute greatly in reducing production costs of vegetables, making the industry more competitive and sustainable. Through proper irrigation, average vegetable yields can be maintained (or increased) while minimizing environmental impacts caused by application of excess water and subsequent nutrient leaching. Recent technological advances have made soil water sensors available for efficient and automatic operation of irrigation systems. Automatic soil water sensor-based irrigation requires maintenance of a desired soil water range in the root zone that is optimal for plant growth. The target soil water status is usually set in terms of soil tension or matric potential (expressed in kPa or cbar, 1 kPa ¼ 1 cbar), or volumetric moisture (expressed in vol.% of water in a volume of undisturbed soil). Another benefit of automatic irrigation techniques is convenience. In a previous experience working with a soil moisture-based automatic irrigation system, Dukes et al.[1] found that once such a system is set up and verified, only weekly observation is required. This type of system adapts to the amount of water applied according to plant needs and actual weather conditions throughout the season. This translates not only into convenience for the manager but into substantial water savings compared to irrigation management based on average historical weather conditions.
