Typical Chernozem on the Bălţi Steppe has suffered substantial loss of soil organic matter from the whole soil profile under arable farming: black fallow, continuous cropping and various crop rotations. In the absence of optimal soil fertilization, uncompensated losses of soil organic carbon are driven by the uptake of nitrogen for crop yield formation predominantly from the mineralization of soil organic matter, as well as the acceleration of mineralization by ploughing. A sustainable and resilient farming system can be achieved only by restoration of soil fertility within diverse crop rotations.