Dal-lake’s dominant submerged aquatic weed valorisation for bioremediation of nitrogenous and metallic stressors from a variety of aquaculture waters

The present study aims to determine ammonia, nitrite, lead (II) and chromium (VI) removal efficiencies of the products developed from aquatic weeds, Ceratophyllum demersum and Hydrilla verticillata, collected from Dal-lake, for the first time, from a variety of aquaculture waters (pond, aquaponics, and ornamental) under controlled conditions, followed by a wet-lab-based large-scale experiment. Aquatic weeds were found to be effective in the removal of ammonia, nitrite, Pb(II), and Cr(VI) from a variety of aquaculture waters, which can be attributed to adsorption and ion exchange of priority pollutants on functional moieties, alkali metals, and alkaline earth metals present in the aquatic weeds. The experimental results showed that ammonia and nitrite removal was effective at pH 7.5, whereas Cr(VI) removal was observed at pH 2 in treatment with 100 mg/L and 200 mg/L of weed. The average lead biosorption observed was 14 mg/g. The removal efficiencies observed were 60-65% for ammonia, 50% for nitrite, 99% for Cr(IV), and 90% for lead. By integrating bioremediation and livelihood generation, this initiative can not only contribute to environmental restoration but also create sustainable opportunities for local communities, fostering economic growth and social well-being. Utilizing aquatic weeds for bioremediation to generate livelihood opportunities for local communities can be an innovative and sustainable approach. Capacity building of the farmers for plant-assisted bioremediation is also suggested, enabling them to effectively integrate these techniques into their aquaculture operations.