Effects of Different Nitrogen and Phosphorus Ratios on the Growth, Nutritional Value, and Nutrient Removal Efficiency of Wolffia globosa

This study investigates the influence of varying nitrogen-to-phosphorus (N:P) ratios on the growth, nutritional composition, and nutrient removal efficiency of Wolffia globosa under controlled laboratory conditions. Six treatments with N:P ratios of 1:3, 1:2, 1:1, 2:1, 3:1, and a control were evaluated. The findings indicate that a balanced N:P ratio (1:1) promotes optimal growth, resulting in the highest biomass yield and specific growth rate (SGR = 0.120 g/day). In contrast, a nitrogen-rich ratio (3:1) enhanced protein accumulation and phosphorus removal, while the 2:1 ratio favored nitrogen uptake. These results reflect underlying physiological responses, including nitrogen assimilation and phosphorus uptake mechanisms regulated by nutrient balance. A trade-off was observed between biomass production and phosphorus removal efficiency, suggesting that different N:P ratios may be suited to specific application goals. This study contributes to a more comprehensive understanding of how macronutrient balance affects growth and metabolism in W. globosa and offers practical implications for optimizing its use as both a sustainable protein source and a biological agent for nutrient remediation in wastewater treatment systems.