Soil fertility - the only possible foundation for more sustainable agriculture

The reductionist approach to intensification of agriculture has created unanticipated economic, ecological and social consequences. Across the steppes, elimination of perennial legumes from the crop rotation and even elimination of crop rotation, large areas under black fallow, and the demise of crop and animal husbandry are draining soil fertility - and in many places loss of the soil itself. Data from long-term field experiments demonstrate the importance of perennial legumes in crop rotation for nitrogen- and water-use efficiency, accumulation of soil organic matter in deeper soil layers, and resilience in the face of drought.