Determining the regional cropland SOC dynamics would not only provide a better understanding of the factors and processes regulating C cycling and balance in the agro-ecosystems but would also provide insight into the effectiveness of methods for enhancing soil quality and plant production,as well as reducing greenhouse gas emissions.Our objective in this study is to quantitatively estimate regional-scale spatiotemporal changes in soil organic carbon (SOC) across Australian wheat-growing areas between 1960 and 2010,so that policy-makers can make sensible,region-oriented decisions regarding SOC management.