Journal Articles, Scientific Papers, Posters, Theses and Dissertations

Development of a real-time wireless sensor network-based information system for efficient irrigation of upland and lowland crop production systems

Ruzell Ramirez, Edzel Agulto, Ziran Zhang, Steven Glaser, Victor Ella, and Joseph Hermocilla

This study developed a real-time web-and WSN-based information system for efficient irrigation water management and automation of drip-irrigated upland crop and intermittently-irrigated lowland crop production systems. The web-based system uses Flutter and DART, which is an open-source software development kit that is used to develop applications for Android, iOS, Linux, Mac, Windows, Google Fuchsia, and the web. The WSN-based system uses state-of-the-art hardware and sensors for real-time monitoring of soil moisture, water level and weather conditions. The sensors are wirelessly connected in a low- power mesh network that sends data to a central server. The sensor readings are uploaded to the web application via MQTT, which generates charts and graphs for data analysis. The sensor readings were compared with measurements from conventional instruments. The system in this study can improve irrigation efficiencies under both upland and lowland crop production systems, minimize water losses and improve agricultural productivity.

Keywords: wireless sensor networks, web-based information system, drip irrigation, alternate wetting and drying

Development of Low-cost Soil Moisture Monitoring System for Efficient Irrigation Water Management of Upland Crops

Marielle Aringo, Camille Martinez, Orlando Martinez, and Victor Ella

With the advancement of information and communication technology, various types of soil moisture sensors have been developed. Coupled with data loggers, these sensors could prove useful in monitoring soil moisture in upland crop production areas which in turn could be used for efficient irrigation water management. However, most of these sensors are costly and unaffordable to most farmers in developing countries. Hence, a low-cost soil moisture monitoring system intended to facilitate irrigation water management in upland crop production systems was developed in this study. The device was built with a capacitive soil moisture sensor, an ESP8266 Wi-Fi mini board, and a datalogging shield with RTC. Soil moisture measurements are transmitted via ESP-NOW to a server which also uses an ESP8266 Wi-Fi mini board. The low-cost soil moisture monitoring system was evaluated based on its measurement of volumetric water content and transmission of data via ESP-NOW. The performance of the capacitive soil moisture sensor was compared with the ICT International MP306 soil moisture sensor. Statistical analyses showed that volumetric water contents measured by the capacitive soil moisture sensor are comparable to those of the MP306 soil moisture sensor, thus conceived as a low-cost alternative to the high-end sensor. Moreover, test results on the range of ESP-NOW showed that data can be successfully transmitted over long distances. Hence, the low-cost soil moisture monitoring system may be integrated with other technologies to enable irrigation scheduling and automation for efficient irrigation water management in upland crop production systems.

Development of mobile application for wireless sensor networks for efficient irrigation water management

Edzel Agulto and Victor Ella

The evolution of smart phones has necessitated the development of mobile applications designed to perform a wide variety of functions. In the field of agriculture, mobile applications are currently used to monitor environmental parameters such as ambient temperature, humidity, soil moisture, water level, among others. A mobile application intended to monitor irrigation-related parameters and to control solenoid valves for irrigation automation was developed in this study. The mobile application was written using Flutter software development kit, and the Dart programming language. The mobile application communicates with the cloud server using a REST API written in JavaScript. The data acquired from the cloud server are presented as the current sensor reading and graphs. On the other hand, the mobile application controls the solenoid valves by sending designated bytes of data to the cloud server. The mobile application developed in this study was designed to be integrated with both low-cost sensors and the Smartmesh IP sensors to enable real-time monitoring and data visualization, and facilitate irrigation scheduling and manual irrigation control. The mobile application developed in this study may be used for efficient irrigation water management of upland crop production systems and for agricultural modernization in the Philippines and other developing countries.

Keywords: Flutter, Dart, Real-Time Monitoring, Mobile Application, Smart Irrigation

Performance evaluation of a water level sensor under various turbidity levels in lowland crop production systems

Gamiello Pereira, Ruzell Ramirez, Edzel Agulto, and Victor Ella

The practice of alternate wetting and drying (AWD), a water-saving technology in lowland crop production systems, can be greatly facilitated using wireless water level sensors. However, these sensors generally work under clear water conditions. The sensitivity of these sensors to turbidity is important for accurate water level measurement and appropriate irrigation scheduling. This study aimed to evaluate the performance of a high-end water level sensor under various turbidity levels. The sensor is essentially of the submersible pressure transducer type which requires connection to a NeoMote system. The performance tests were performed in the laboratory using various levels of turbidity replicated three times with clear water as control. Water samples collected from a typical lowland rice production system were used to formulate various turbidity levels. The readings of the sensors were compared with manual readings for each turbidity level in all replications. Based on the data collected, analysis of variance and regression analysis were performed to analyze the statistical significance of the differences among treatments and to establish mathematical relationships between water level measurement and turbidity. Results suggest that turbidity affects the accuracy of the water level sensor. To address the effect of turbidity on the accuracy of sensor readings, a unified calibration equation was then derived that may be used for field application under turbid water conditions. Results of this study can be used to improve the accuracy of water level monitoring in irrigated lowland crop production systems employing alternate wetting and drying technology to further increase irrigation efficiencies and augment water savings particularly during the dry season or water-scarce conditions for a more sustainable crop production.

Keywords: water level sensor; turbidity; alternate wetting and drying

Hydraulic Performance Evaluation of Low-Cost Gravity-Fed Drip Irrigation Systems Under Constant Head Conditions

Camille Martinez, Chen Wu, Arthur Fajardo, and Victor Ella

The use of drip irrigation for upland crop production has gained popularity in developing countries due to its relatively high water-use efficiency. To maximize the efficiency of this irrigation method, it is important to evaluate its hydraulic performance in terms of emitter discharge and water distribution uniformity under various operating heads. In this study, the hydraulic performance of two locally available low-cost drip irrigation kits – referred to in this study as Drip Kit A and Drip Kit B – was assessed and compared under constant head conditions. Both drip kits are composed of a 1000-L intermediate bulk container (IBC) tank, 10-m submain line, 20-m lateral lines spaced 0.75 m apart, and cascade labyrinth emitters spaced 0.30 m apart along the laterals. Operating heads of 2.5, 3.5, 4.0, 4.5, 5.0, 5.5 m were used and maintained throughout the trials with the use of an overflowing tank. The submain and lateral lines were levelled (0% slope). Sampling of discharge rates was done for one-third of the total number of emitters for each of the tests performed. Results showed that the overall system emitter discharge rate generally increases with increasing operating head. Moreover, emitters farther from the submain line generated relatively lower discharge rates than those closer to it. Analysis of the experimental data showed that the Christiansen’s coefficient of uniformity (CU), emission uniformity (EU), and coefficient of variation (CV) ranged from 97.5 to 98.5, 95.9 to 97.7, and 0.02 to 0.04 for the drip systems tested. Further statistical analysis also showed that varying the operating heads does not have a statistically significant effect (α=5%) on the CU, EU, and CV of the system. Based on the results, Drip Kit B performed better than Drip Kit A in terms of water distribution uniformity. However, the latter could generate higher emitter discharge rates than the former. For both drip kits, an operating head of 2.5-m is recommendable for a 200m2 plot, from the practical standpoint. This study has generated important empirical data that could serve as basis for maximizing the performance efficiency of locally available drip irrigation systems for a more efficient irrigation water management.

Assessment of potential for adoption of wireless sensor network technology for irrigation water management of high value crops in the Philippines

Nikki Panaligan, Marielle Aringo, and Victor Ella

The integration of wireless sensor network (WSN) in high value crop production systems can provide numerous benefits such as water savings, continuous and real-time monitoring of farm status, higher return on investment, and agricultural modernization. It can also address such issues as inadequate manpower, aging farmers, climate change and climate variability and can therefore contribute to sustainable crop production. This paper aims to assess the potential for adoption of WSN technology for irrigation water management of high value crops in the Philippines through market survey with farm owners and farm managers as respondents. Potential respondents were identified in various regions in the country using non-random sampling methods. An online survey and printed survey forms were used and distributed, depending on the preference of the respondent. The survey basically includes questions about farm information, problems related to water management, familiarity with WSN, and willingness to adopt, among others. Results of analysis of survey data indicate a strong potential for adoption of WSN technology. Based on the results, 83% of the respondents expressed willingness to adopt the WSN technology if properly demonstrated and if it will give a high return on investment. On the other hand, 76% of the respondents are willing to adopt WSN regardless of the costs provided there is a high return on investment. However, only a little more than half of the respondents are willing to adopt the WSN technology for the sake of modernization. Results also showed a strong potential for adoption of WSN technology using locally-developed sensors with 81% of the respondents provided affirmative answers. Chi-square test results indicated that sex, gross annual household income, membership to farmer’s association, land tenure status, and familiarity with WSN technology are the primary determinants of the potential for adoption regardless of the conditions imposed. However, educational attainment also played a role in the adoption of WSN technology if the purpose is agricultural modernization and if there is a higher return on investment despite some budgetary allocation for the initial costs. Results of this study could serve as basis for developing commercialization schemes, strategies for upscaling and for agricultural policy formulation.

Keywords: wireless sensor network, market survey, WSN technology adoption, high value crops, irrigation water management