Integrated Use of Fly Ash, Blue-Green Algae, and Bio- Fertilizers for Sustainable Rice Cultivation in Fly Ash- Contaminated Environment

Abstract

The coal-fired power plants generate a high volume of fly ash (FA), a significant solid waste with considerable environmental and health
consequences. The stagnation of FA around heat-generating factories causes pollution due to toxic heavy metals. These pollutants
jeopardize biodiversity, disrupt ecosystems, and pose a serious threat to human health, and agricultural crop land contaminated by FA,
such as rice (Oryza sativa L.). Despite FA having some effective plant nutrients (Ca, S, B, Mo, Cu, Zn, and Fe), it has deficiencies of essential
nutrients such as N, which makes it ineffective as a direct fertilizer. However, green algae, a population of nitrogen-fixing photosynthetic
microbes that grows in paddy fields, is the answer to it. Some heterocystous strains are the ones that rely on the B availability in FA
to enhance maximum fixation of N. This paper undertakes a synergistic application of green algae and FA, and chemical fertilizers to
improve soil fertility, reduce heavy metal toxicity, and promote sustainable disease-resistant rice production on the FA-contaminated
land, emphasizing heavy metal bioaccumulation, detoxification, and bioremediation. The combined approach is sustainable, cheap,
and eco-friendly in terms of FA waste management, which is in line with the principles of the circular economy, and restoring the
environment and securing food in the future.