A study in Shaoyang county, China, looked at soil potassium levels after land consolidation. They found that the soil had optimal levels of total potassium, slow-release potassium, and availability potassium. The type of parent material greatly influenced potassium content, with soils from fluvial deposits having the highest levels, soils from Quaternary red clay having moderate levels, and soils from limestone having the lowest levels. Soils from limestone may need more potassium fertilizer to improve fertility.