IoT Application for Water Quality Monitoring: Nitrates

The intensive agricultural fertilization used for large scale food production generates an increase in the concentration of nitrates in water systems, contamination of water for human consumption and eutrophication of surface waters. Therefore, nitrates monitoring is a must practice in a basin receiving high agricultural activity. Discrete and sporadic samples analysis might reveal spatial differences in concentration, but continuous samples analysis gives the information about the origin, hydrological dynamics, transport and the bioprocessing of the nitrates. Here we present a design of an autonomous system for nitrates remote monitoring that uses an adjustable but continuous sampling flow, UV spectroscopy and Internet of Things (IoT) to directly perform and control the system calibration and nitrates quantification and, a strategy to optimize data generation and the monitoring resolution: a conductivity sensor used as a sampling frequency trigger.