| Autor: |
Wade J; School of Environment & Natural Resources, The Ohio State University, Ohio, USA. jordonwade@gmail.com.; Department of Crop Sciences, University of Illinois, Urbana-Champaign, Illinois, USA. jordonwade@gmail.com., Culman SW; School of Environment & Natural Resources, The Ohio State University, Ohio, USA., Logan JAR; College of Education and Human Ecology, The Ohio State University, Ohio, USA., Poffenbarger H; Department of Plant and Soil Sciences, University of Kentucky, Kentucky, USA., Demyan MS; School of Environment & Natural Resources, The Ohio State University, Ohio, USA., Grove JH; Department of Plant and Soil Sciences, University of Kentucky, Kentucky, USA., Mallarino AP; Department of Agronomy, Iowa State University, Iowa, USA., McGrath JM; Department of Plant and Soil Sciences, University of Kentucky, Kentucky, USA., Ruark M; Department of Soil Science, University of Wisconsin - Madison, Wisconsin, USA., West JR; Department of Soil Science, University of Wisconsin - Madison, Wisconsin, USA. |
| Abstrakt: |
Nitrogenous fertilizers have nearly doubled global grain yields, but have also increased losses of reactive N to the environment. Current public investments to improve soil health seek to balance productivity and environmental considerations. However, data integrating soil biological health and crop N response to date is insufficient to reliably drive conservation policy and inform management. Here we used multilevel structural equation modeling and N fertilizer rate trials to show that biologically healthier soils produce greater corn yields per unit of fertilizer. We found the effect of soil biological health on corn yield was 18% the magnitude of N fertilization, Moreover, we found this effect was consistent for edaphic and climatic conditions representative of 52% of the rainfed acreage in the Corn Belt (as determined using technological extrapolation domains). While N fertilization also plays a role in building or maintaining soil biological health, soil biological health metrics offer limited a priori information on a site's responsiveness to N fertilizer applications. Thus, increases in soil biological health can increase corn yields for a given unit of N fertilizer, but cannot completely replace mineral N fertilization in these systems. Our results illustrate the potential for gains in productivity through investment in soil biological health, independent of increases in mineral N fertilizer use. |
