Advancing Wireless Sensor Networks for Irrigation Management of Ornamental Crops: An Overview

Abstract

<jats:p>Wireless sensor networks (WSNs) transmit sensor data and control signals over long distances without the need for expensive infrastructure, allowing WSNs to add value to existing irrigation systems since they provide the grower with direct feedback on the water needs of the crop. We implemented WSNs in nine commercial horticulture operations. We provide an overview of the integration of sensors with hardware and software to form WSNs that can monitor and control irrigation water applications based on one of two approaches: 1) “set-point control” based on substrate moisture measurements or 2) “model-based control” that applied species-specific irrigation in response to transpiration estimates. We summarize the economic benefits, current and future challenges, and support issues we currently face for scaling WSNs to entire production sites. The series of papers that follow either directly describe or refer the reader to descriptions of the findings we have made to date. Together, they illustrate that WSNs have been successfully implemented in horticultural operations to greatly reduce water use, with direct economic benefits to growers.</jats:p>

Social and Economic Aspects of Water Use in Specialty Crop Production in the USA: A Review

“…Water savings alone were not adequate to encourage investment in sensor networks; growers changed practice only when there was a financial incentive from reduced production time, lower plant losses, or reduced chemical inputs. Changes in practice (i.e., sensor network for irrigation control) were often applied to additional areas under production after the technology was proven effective, accurate, and easy to use and maintain [49][50][51]. Reduction in labor requirements and pumping costs were appreciable for sensor network applications in containerized pot-in-pot production system [52].…”

“…Regulators also need to be informed about the proactive practices growers have implemented to protect the environment and conserve water resources, so that the consequences of proposed regulations to growers are understood in the context of the changes growers have already implemented, and to better understand the implications of proposed regulatory changes have on grower's profitability and the environment. Implementing new technologies and practices may also help growers reduce water needs, both by changing practices to enhance operational water use efficiency and by developing the infrastructure capacity to treat and reuse water [51,63].…”

Green Roof Ecosystems

“…Currently no consensus exists on the most appropriate modeling approach for green roof contexts. Monitoring approaches including the development of inexpensive wireless sensor networks could provide a practical way of directly measuring the real-time water status of a roof in high spatial and temporal resolution (Starry et al 2011;Lea-Cox et al 2013;Chap. 2).…”

The influence of water uptake on matric head variability in a drip-irrigated root zone

“…In recent years there has been a plethora of work regarding various sensors and sensor networks for improving irrigation management and efficiency (Capraro et al, 2008;Coates et al, 2013;Evett et al, 2011;Goumopoulos et al, 2014;Greenwood et al, 2009;Lea-Cox et al, 2013;van Iersel et al, 2013;Vellidis et al, 2008). However, information concerning the location of sensors is either nonexistent, empirical, experiential, or based on complicated spatiotemporal experiments which are site and crop specific (Capraro Dobbs et al, 2013;Hagen et al, 2014;Kloss et al, 2014;Pardossi et al, 2009;Phillips et al, 2014;Shi et al, 2015;Soulis et al, 2015;van Iersel et al, 2013). Among these sensors, the tensiometer is considered one of the best and simple devices to measure the matric head in soils (Taylor, 1965) and, hence, water availability.…”

“…Automated drip irrigation systems often utilize this concept to trigger irrigation. A major obstacle in obtaining a true mean value from tensiometer measurements, at the field scale, lies in the soil spatial variability (Webster, 1966) and root growth patterns (van Iersel et al, 2013), which causes tensiometer measurements to vary depending on their location. The higher the measurement variability, the more tensiometers are needed to evaluate the true matric head mean in the soil.…”