Plant mediation of nitrogen mineralization via shifts in rhizosphere carbon allocation

NON-TECHNICAL SUMMARY: Increasing soil organic matter offers many potential benefits for cropping system adaptation and mitigation of climate variability and change, including improved drought tolerance, temperature regulation, nutrient use efficiency, and yield stability. Cover crops are an important strategy for increasing soil organic matter by extending the period of plant growth. Cover crops also reduce erosion and nutrient losses by providing soil coverage during time periods forecast to experience more high precipitation events in the Mid-Atlantic Region. In addition, nitrogen inputs from legume cover crops can reduce the demand for fossil-fuel based fertilizer inputs, resulting in decreased greenhouse gas emissions. This research will improve our understanding of cover crop effects on nutrient cycling in cropping systems using greenhouse and field experiments. We will integrate results into an existing cropping systems model to estimate the relative importance of cover crop effects on carbon and nitrogen cycling on grain farms. Through collaborations with a larger cover crop research team, we will integrate results into a broad suite of outreach activities through which farmers will increase understanding of the multiple ecosystem services provided by cover crops and will increase cover crop adoption.