Evaluating the Productivity of Jambu (Acmella oleracea) with Effluent from Tambaqui Culture: An Integrated Aquaculture—Agriculture Approach for the Amazon

The global demand for sustainable food systems requires innovative strategies that reconcile productivity with environmental stewardship, particularly in biodiversity-rich regions such as the Amazon. This study evaluated the cultivation of Acmella oleracea (jambu) using effluent from Colossoma macropomum (tambaqui) aquaculture as a partial substitute for chemical fertilizer. Five treatments were tested under greenhouse conditions: 100% fertilizer, 75% fertilizer, 50% fertilizer, 25% chemical, and 0% fertilizer. Significant treatment effects were observed for leaf number, plant height, stem diameter, and shoot biomass, while root biomass showed no differences. Treatments with 100%, 75%, and 50% fertilizer exhibited statistically similar performance across several growth parameters, indicating that up to 50% of the chemical fertilizer can be replaced by aquaculture effluent without significant yield reduction. Treatments with 50% fertilizer and 0% fertilizer showed reduced growth and higher tissue accumulation of nitrate and ammonium, reflecting nutritional imbalances. In parallel, tambaqui showed 100% survival and satisfactory growth, confirming the stability of the integrated system. These results highlight that, although exclusive use of effluent is insufficient to match chemical fertilizer, partial substitution represents a viable strategy to reduce input costs and recycle nutrients, reinforcing the bioeconomic potential of aqua-culture–agriculture integration in the Amazon.