|O'DELL, DEB - University Of Tennessee|
|EASH, NEAL - University Of Tennessee|
|HICKS, BRUCE - Metcorps|
|ZAHN, JAMES - Dupont Tate & Lyle Bio Products Company|
|OETTING, JOEL - University Of Tennessee|
|Sauer, Thomas - Tom|
|LAMBERT, DAYTON - University Of Tennessee|
|LOGAN, JOANNE - University Of Tennessee|
|GODDARD, JOHN - University Of Tennessee|
Submitted to: Open Journal of Soil Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/8/2019
Publication Date: 6/20/2019
Citation: O'Dell, D., Eash, N.S., Hicks, B.B., Zahn, J.A., Oetting, J.N., Sauer, T.J., Lambert, D.M., Logan, J., Goddard, J. 2019. Nutrient source and tillage effects on maize: I. Micrometeorological methods for measuring carbon dioxide emissions . Open Journal of Soil Science. 2(1):1-10. https://doi.org/10.2134/age2019.02.0008.
Interpretive Summary: There is increasing interest in recycling organic byproducts for agricultural uses. In this study a fermentation waste product that had previously been put in a landfill was instead applied to a corn field in Tennessee to serve as a source of nutrients and to increase the soil organic matter content. Corn yield and carbon dioxide emissions were compared to a field with standard practices. The field with byproduct application had a higher yield that was attributed to the amount of nutrients it contained. Byproduct application also resulted in greater CO2 exchange with the atmosphere, which was partially offset by the greater crop growth. Further study over more growing seasons with improved byproduct application techniques is required. This research is of interest to growers and scientists interested in enhancing the recycling of nutrients and organic matter contained in waste materials.
Technical Abstract: Global agriculture is challenged to increase soil carbon sequestration and reduce greenhouse gas emissions while providing products for identifying and recovering the resource value contained in waste, especially organic materials, and has become an important component in the circular economy. Heat-inactivated spent microbial biomass is an industrial fermentation waste product and has nutrients that could be used as a fertilizer replacement for agriculture. Waste reutilization in agriculture may reduce CO2 emissions and provide improved environmental sustainability. This study examined fertilizer replacement potential of heat-inactivated microbial biomass (spent biomass) generated from the production of 1,3-propanediol. The spent biomass applications provided yields typical of applications of low C:N products with yields increasing with increasing rates. Mechanical disintegration of spent microbial biomass into smaller clumps with greater surface area is needed to enhance mineralization. Carbon dioxide emissions were greater over a field with spent biomass applications (emitting 440 g CO2 m-2 yr-1) compared to a field with standard farmer practice (sequestering 348 g CO2 m-2 yr-1) from August 2016 to August 2017 using eddy covariance systems to measure the total CO2 flux. Nighttime CO2 emissions were greater as detected by Bowen ratio energy balance and aerodynamic methods. By comparing CO2 emissions, nutrient cycling of spent biomass in the soil/plant ecosystem for improving productivity and increasing soil organic matter can be better understood.