Agronomic and Climate Benefits of Basalt Rock Dust: A Review of Silicate Rock Applications in Agriculture

Enhanced weathering, Soil mineralization, Carbon sequestration, Tropical Soil.A freshly derived and ground mafic igneous rock called basalt represents a sustainable alternative for enhancing the fertility of agricultural soils and improving the sequestration of atmospheric CO₂. Minerals like feldspar, micas, zeolites, and major oxides like 37.76–59.64% (SiO2), 11.77–14.32% (Al₂O₃), 5.57–14.75% (CaO), 5.37–9.15% (MgO), 10.1–20.93% (Fe₂O₃), 1.7–6.69% (K₂O), 1.4–3.34% (Na2O), and 1.81–3.73% (TiO₂) are reported as its constituents. Through the process of mineral weathering, nutrients are released gradually from the dust of basalt, thereby improving soil nutrient structure and availability. For most agronomic trials involving mafic silicate rocks, particularly in highly weathered tropical soils, yield improvements are reported as a result of basalt incorporation. According to recent findings, the amendments with basalt increase plant height, stem diameter, biomass, and accumulation of macronutrients like phosphorus, potassium, sulphur, calcium, and magnesium in tropical cropping systems. According to the review in this study, other elemental compositions and chemical parameters of soil, such as potassium, calcium, magnesium, and pH, were reported to be improved as a result of basalt addition. The climate benefits of basalt addition through the process of enhanced weathering and 0.3 t CO₂ t⁻¹ carbon capturing potential were emphasized. Despite the promising reports on the agricultural and climate use of basalt in tropical regions, limited studies under temperate conditions remain a challenge. The expansion of field-scale validation and the understanding of basalt parameters such as particle sizes, application rates, application periods, and its mineral constituents are crucial to derive its full potential for agronomic and climate benefits.