Relating four-day soil respiration to corn nitrogen fertilizer needs across 49 U.S. Midwest fields

Authors

G. M. Bean, Soil Health Institute, Morrisville, NCFollow
Newell R. Kitchen, USDA-ARSFollow
Kristen S. Veum, USDA, Agricultural Research ServiceFollow
James J. Camberato, Purdue UniversityFollow
Richard Ferguson, University of Nebraska-LincolnFollow
Fabian G. Fernandez, University of Minnesota - Twin CitiesFollow
David W. Franzen, North Dakota State University--FargoFollow
Carrie A.M. Laboski, University of Wisconsin-MadisonFollow
Emerson Nafziger, University of IllinoisFollow
John E. Sawyer, Iowa State UniversityFollow
Matt Yost, Utah State UniversityFollow

ORCID IDs

G. Mac Bean https://orcid.org/0000-0002-2206-3171

Kristen S. Veum https://orcid.org/0000-0002-6492-913X

Fabian G. Fernandez https://orcid.org/0000-0002-9539-0050

David W. Franzen https://orcid.org/0000-0003-4862-8086

John E. Sawyer https://orcid.org/0000-0003-4080-9616

Matt Yost https://orcid.org/0000-0001-5012-8481

Document Type

Article

Date of this Version

2020

Citation

Soil Sci. Soc. Am. J. 2020;84:1195–1208.

Comments

U.S. government work

Abstract

Soil microbes drive biological functions thatmediate chemical and physical processes necessary for plants to sustain growth. Laboratory soil respiration has been proposed as one universal soil health indicator representing these functions, potentially informing crop and soil management decisions. Research is needed to test the premise that soil respiration is helpful for profitable in-season nitrogen (N) rate management decisions in corn (Zea mays L.). The objective of this research was two-fold: (i) determine if the amount of N applied at the time of planting effected soil respiration, and (ii) evaluate the relationship of soil respiration to corn yield response to fertilizer N application. A total of 49 N response trials were conducted across eight states over three growing seasons (2014–2016). The 4-day Comprehensive Assessment of Soil Health (CASH) soil respiration method was used to quantify soil respiration. Averaged over all sites, N fertilization did not impact soil respiration, but at four sites soil respiration decreased as N fertilizer rate applied at-planting increased. Across all siteyears, soil respiration was moderately related to the economical optimum N rate (EONR) (r² = 0.21). However, when analyzed by year, soil respiration was more strongly related to EONR in 2016 (r² = 0.50) and poorly related for the first two years (r² < 0.20). These results illustrate the factors influencing the ability of laboratory soil respiration to estimate corn N response, including growing-season weather, and the potential of fusing soil respiration with other soil and weather measurements for improved N fertilizer recommendations.