LIBS: a rapid nutrition monitoring tool for hydroponic crops and nutrient supply

Hydroponic systems offer controlled environments for crop growth, demanding precise and continuous monitoring of nutrient levels to optimize plant health and yield. In-situ monitoring of crops and nutrient supply plays a pivotal role in comprehensively understanding their mineral constituents, facilitating early correction of nutritional deficiencies. In addition to detecting nutritional deficiencies, this process offers farmers guidance regarding precise crop cultivation practices. However, current monitoring techniques are often labor-intensive, laboratory-based, and require tedious sample preparation. In this context, we propose an optically modified direct spectrograph-coupled laser induced breakdown spectroscopy (LIBS) system capable of detecting and quantifying key nutrients including potassium, calcium, and magnesium. In this work, in-situ nutrient monitoring of the nutrient supply and lettuce crop was performed using singleshot LIBS. Analysis of the results elucidates that highly sensitive and reproducible LIBS spectra can be directly obtained without any sample preparation. Additionally, we assess the feasibility and accuracy of LIBS in capturing dynamic changes in nutrient concentrations, providing valuable insights into nutrient uptake kinetics and potential imbalances. This research showcases LIBS as a valuable tool for real-time monitoring in hydroponic systems, highlighting its potential for remote analysis in agriculture. It facilitates informed decision-making and enhances the overall efficiency of nutrient management practices in agricultural fields.