Algae: A cutting-edge solution for enhancing soil health and accelerating carbon sequestration – A review
Sanjita Gurau, Muhammad Imran, Ram L. Ray
Abstract
Algae represent a sustainable resource with significant applications in agriculture, environmental management, and waste treatment. This review highlights the multifaceted roles of algae, particularly microalgae, in enhancing soil health, facilitating carbon sequestration, treating wastewater, and producing biochar. Algae improve soil fertility in agriculture by enhancing biological, chemical, and physical properties. They contribute to increased carbon content and soil aggregation by releasing extracellular polymeric substances (EPS) while promoting beneficial microbial populations that support nutrient cycling. Microalgae, such as Chlorella, have been shown to enhance nutrient levels in soil and improve water retention, ultimately fostering healthier crop growth. As global CO 2 emissions rise, algae present a promising solution for carbon sequestration. Through photosynthesis, they efficiently absorb atmospheric CO 2 , converting it into biomass at rates significantly higher than traditional plant systems. This natural process positions microalgae as a viable alternative for mitigating climate change, with the ability to sequester carbon while simultaneously generating biomass for various applications. Algae play a crucial role in wastewater treatment by utilizing nutrient-rich effluents for growth. Microalgae effectively remove contaminants while producing biomass suitable for biofuels and fertilizers. Recent studies demonstrate that municipal wastewater is an effective growth medium, achieving high nutrient removal rates and reducing chemical oxygen demand. The conversion of algal residues into biochar through thermochemical processes addresses the challenge of algal waste management. Algal biochar exhibits favorable properties, including high carbon content and significant surface area, making it effective for CO 2 adsorption and soil amendment. This process enhances carbon sequestration and improves soil quality. In summary, integrating algae into agricultural and environmental practices presents a holistic approach to enhancing soil health, combating climate change, treating wastewater, and promoting sustainable resource management. Through their diverse applications, algae offer innovative solutions to some pressing challenges faced in agriculture and environmental conservation, contributing to a more sustainable future. • High potential to enhance soil productivity, and contribute to climate change mitigation. • Application of algae as biofertilizers presents a promising and sustainable alternative. • Algae has potential to enhance carbon sequestration and improves soil quality.