Articles
Real time monitoring of nitrate, ammonium, and potassium in closed-loop hydroponics by customized use of commercially available ion-specific electrodes
Article number
1369_9
Pages
75 – 84
Language
English
Abstract
Nutrient monitoring allows improved understanding and optimization of crop production.
Closed-loop hydroponics and reuse of nutrients from other processes may result in dynamic nutrient solutions requiring real-time monitoring to verify and control nutrient levels.
While ion-specific electrodes may be suited for such applications, typical challenges relate to drift, selectivity, and stability, with biofouling adding complications for long-term use.
A nutrient monitoring system for ammonium, nitrate and potassium is presented, based on at-line implementation of readily available ion specific electrodes.
Customized compensation strategies mitigated and nearly abolished drift, selectivity, and ion matrix vulnerabilities in typical hydroponic conditions.
Combined with automated liquid handling, an analytical system was demonstrated for long-term and near real-time monitoring of the nutrient solution without human intervention.
A one-month crop cultivation campaign in closed-loop hydroponics including quality assurance by various control solutions illustrated accuracies within ±2 mg N or K L-1, or ±2% of the measured value.
The results illustrate the applicability of the presented system in hydroponics and highlight principles that may hold relevance also for other systems and applications.
Closed-loop hydroponics and reuse of nutrients from other processes may result in dynamic nutrient solutions requiring real-time monitoring to verify and control nutrient levels.
While ion-specific electrodes may be suited for such applications, typical challenges relate to drift, selectivity, and stability, with biofouling adding complications for long-term use.
A nutrient monitoring system for ammonium, nitrate and potassium is presented, based on at-line implementation of readily available ion specific electrodes.
Customized compensation strategies mitigated and nearly abolished drift, selectivity, and ion matrix vulnerabilities in typical hydroponic conditions.
Combined with automated liquid handling, an analytical system was demonstrated for long-term and near real-time monitoring of the nutrient solution without human intervention.
A one-month crop cultivation campaign in closed-loop hydroponics including quality assurance by various control solutions illustrated accuracies within ±2 mg N or K L-1, or ±2% of the measured value.
The results illustrate the applicability of the presented system in hydroponics and highlight principles that may hold relevance also for other systems and applications.
Publication
Authors
Ø.M. Jakobsen, M. Schiefloe, A.I.K. Jost
Keywords
hydroponics, nutrients, monitoring, recycling, ISE
Online Articles (31)