A Yale-led study reports that farmers in the Mississippi River Basin who add limestone to their fields are storing more carbon dioxide in the soil than they release through the practice. This agricultural technique, known as liming, is typically used to reduce soil acidity and improve crop conditions.
The research frames the finding as a major carbon sink, with the effect described as broad and far-reaching as the river basin itself. While liming involves quarrying, transporting, and spreading limestone—steps that generate emissions—the study indicates that the net balance across the region is positive for carbon storage.
The authors suggest this could make liming a more significant factor in carbon accounting than previously recognized. However, the source does not provide details on the magnitude of the sink or the time frame over which it was measured, so the practical implications for climate policy remain to be clarified.