Natalija Arsić is a student researcher from Belgrade, Serbia, specializing in applied chemistry, bio-analytics, environmental science, and research-driven engineering. She is pursuing the Natural Sciences and Mathematics stream at the Fifth Belgrade Grammar School. As a Lead Student Researcher, she has investigated phycoremediation kinetics and developed the Smart Algal Buffer Zone (SABZ), integrating optical sensing and Arduino-based automation. Natalija has received Bronze Medals at IMSEF and ICYS and secured 1st Place in a National Science Competition. She is also an active researcher at Petnica Science Center and the Nikola Tesla Regional Center for Young Talents.

This project establishes an integrated chemical-engineering solution for aquatic remediation by linking microalgal growth kinetics directly with the Smart Algal Buffer Zone (SABZ), an automated, data-driven recovery system. By tracking optical density shifts at 680 nm of Tetradesmus obliquus across varying stoichiometric NPK gradients in a BG11 medium, I determined the precise kinetic threshold where nutrient sequestration (specifically nitrogen and phosphorus ions) reaches maximum efficiency. I translated these laboratory-derived parameters into the SABZ operational logic: embedded optical sensors continuously monitor biomass accumulation in real time, triggering an automated vacuum extraction unit exact at the empirical threshold. This phase-specific biomass separation prevents nutrient desorption back into the water column caused by algal decay, successfully converting agricultural runoff into a high-value, stable organic bio-fertilizer within a closed-loop system.