The potential of clay- and zeolite-based materials used in agricultural systems: Insights into greenhouse gas emission mitigation

Over the past two centuries, the atmospheric concentrations of greenhouse gases (GHGs) have reached unprecedented levels because of population growth and urbanization, uncontrolled industrialization, deforestation and agricultural expansion. While agricultural expansion is inevitable, accelerating in-situ soil storage via adsorption is perhaps one of the most feasible strategies for GHG abatement. For this purpose, naturally occurring and modified forms of clays and zeolites are abundant, cost-effective, and well-characterized materials that have demonstrated significant potential for GHG emission mitigation. This state-of-the-art review examines literature from the past-decade to evaluate the efficacy of clay and zeolite-based materials in mitigating GHGs, with a focus on their application in agricultural systems. It evaluates the effects of these materials on soil health, particularly their role in altering soil physicochemical properties and nutrient availability. Although numerous studies have explored the adsorption capacity of clays and zeolites for GHG emission mitigation purposes, there is a significant research gap regarding their applications within the agricultural sector. The lack of field-scale trials and variation and validation studies is exacerbating this gap. In this context, innovative solutions involving raw and synthetic clays and zeolites in on-farm operations and agricultural soils show promise but require deeper studies. This review therefore addresses this gap and highlights relevant strategies and methodologies.