Community-Participatory IoT Water Quality Monitoring System for Saline Intrusion Management in Orchid Cultivation.

บทคัดย่อ

Saline water intrusion poses a significant threat to orchid cultivation in Thailand’s central provinces, where dry season salinity levels in irrigation canals can reach 4.2 dS/m—well above the 2.0 dS/m tolerance threshold for salt-sensitive orchids. Despite Thailand’s global leadership in orchid exports, with annual revenues exceeding USD 160 million, smallholder farmers lack access to real-time, affordable salinity monitoring tools. Traditional water quality assessments are labor-intensive and reactive, failing to prevent crop damage during critical salinity events. This study developed and evaluated a community-participatory Internet of Things (IoT) water quality monitoring system integrating low-cost electrical conductivity (EC) sensors with mobile alert functionality to support timely salinity management in orchid farming.

The system employed NodeMCU ESP8266 microcontrollers integrated with EC sensors (Salinity ≈ EC × 0.64), pH (ESEN-288), temperature (DS-18B20), and dissolved oxygen sensors. Real-time data visualization and alerting were enabled via the Blynk mobile platform.
Field deployment in Sam Phran District, Nakhon Pathom Province involved 30 farmers (65% of local growers). Sensor calibration was conducted in partnership with Suan Dusit University. Evaluation included technical validation, user satisfaction surveys (usability, performance, design, installation), and an economic impact analysis comparing crop loss data from 2015–2021 with post-implementation results in 2024.

The system demonstrated high technical reliability across parameters and achieved strong user satisfaction (mean scores >4.67/5.0 across all dimensions). Economic analysis revealed a 42% reduction in average annual crop damage, translating to savings of 17,000 THB per household.
The system enabled timely responses, such as alternative water sourcing and irrigation adjustments. Community engagement was evident through user-led maintenance, data sharing, and interest in system expansion.

This study highlights the potential of participatory, low-cost IoT solutions in enhancing agricultural resilience, supporting smart farming adoption among smallholders, and promoting scalable, sustainable salinity management practices.