Climate and land use are important factors affecting the soil carbon pool and organic carbon influx. To explore the characteristics of active organic carbon content and carbon pool management index in farmland soils in typical climate zones, two types of farm land （dry land and paddy fields） and adjacent forest soils in four climate zones （temperate, warm temperate, subtropical, and tropical） in eastern China spanning north to south were selected for study. The permanganate oxidizable carbon （POXC） content in each climate zone was analyzed, and the soil lability of carbon （