TY - JOUR
T1 - Split-nitrogen application with cover cropping reduces subsurface nitrate losses while maintaining corn yields
AU - Preza-Fontes, Giovani
AU - Pittelkow, Cameron M.
AU - Greer, Kristin D.
AU - Bhattarai, Rabin
AU - Christianson, Laura E.
N1 - Funding Information:
This study was supported by the Dudley Smith Initiative in the College of Agricultural, Consumer, and Environmental Sciences at the University of Illinois at Urbana‐Champaign, the Illinois Nutrient Research & Education Council (NREC 2016‐4‐360276‐980), the Foundation for Food and Agriculture Research (Grant Number 534655), and the 4R Research Fund (IPNI‐2017‐USA‐4RF01). The authors would like to express appreciation to all past and current members of the Dr. Laura Christianson's and Dr. Cameron Pittelkow's laboratory for assisting with field data collection and laboratory analysis. We also thank the Curtin family for the collaboration in the project and performing all in‐field management applications, and Dan Schaefer from the Illinois Fertilizer & Chemical Association for assisting with the cereal rye management.
Funding Information:
This study was supported by the Dudley Smith Initiative in the College of Agricultural, Consumer, and Environmental Sciences at the University of Illinois at Urbana-Champaign, the Illinois Nutrient Research & Education Council (NREC 2016-4-360276-980), the Foundation for Food and Agriculture Research (Grant Number 534655), and the 4R Research Fund (IPNI-2017-USA-4RF01). The authors would like to express appreciation to all past and current members of the Dr. Laura Christianson's and Dr. Cameron Pittelkow's laboratory for assisting with field data collection and laboratory analysis. We also thank the Curtin family for the collaboration in the project and performing all in-field management applications, and Dan Schaefer from the Illinois Fertilizer & Chemical Association for assisting with the cereal rye management.
Publisher Copyright:
© 2021 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America
PY - 2021/11/1
Y1 - 2021/11/1
N2 - Artificial subsurface drainage is essential to sustain crop production in many areas but may also impair water quality by exacerbating nitrate (NO3)–nitrogen (N) delivery downstream. Cover crops and split-N application have been promoted as key conservation practices for reducing NO3–N losses, but few studies have simultaneously assessed their effect on water quality and crop productivity. A field study was conducted to evaluate the effects of N application timing and cover crops on subsurface drainage NO3–N losses and grain yield in continuous corn (Zea mays L.). Treatments were preplant-N: 224 kg N ha–1 split-applied with 60% fall + 40% preplant in 2018, or as single preplant applications in 2019 and 2020; split-N: 40% preplant + 60% side-dress (V6–V7); split-N + cover crop (CC): Split-N + cereal rye (Secale cereale L.); and a zero N plot as the control. Across the 3-yr study period, split-N + CC significantly reduced flow-weighted NO3–N concentration and NO3–N loss by 35 and 37%, respectively, compared with preplant-N. However, flow-weighted NO3–N concentration (4.3 mg L–1) and NO3–N loss (22.4 kg ha–1) with split-N were not significantly different from either preplant-N (4.8 mg L–1 and 26.4 kg ha–1, respectively) or split-N + CC (3.1 mg L–1 and 16.7 kg ha–1, respectively). Corn yield was significantly lower in the control treatment but did not differ among N fertilized treatments in any year. These results indicate that combining split-N application with cover crops holds promise for meeting the statewide interim milestone NO3–N reduction target of 15% by 2025 without negatively impacting crop productivity.
AB - Artificial subsurface drainage is essential to sustain crop production in many areas but may also impair water quality by exacerbating nitrate (NO3)–nitrogen (N) delivery downstream. Cover crops and split-N application have been promoted as key conservation practices for reducing NO3–N losses, but few studies have simultaneously assessed their effect on water quality and crop productivity. A field study was conducted to evaluate the effects of N application timing and cover crops on subsurface drainage NO3–N losses and grain yield in continuous corn (Zea mays L.). Treatments were preplant-N: 224 kg N ha–1 split-applied with 60% fall + 40% preplant in 2018, or as single preplant applications in 2019 and 2020; split-N: 40% preplant + 60% side-dress (V6–V7); split-N + cover crop (CC): Split-N + cereal rye (Secale cereale L.); and a zero N plot as the control. Across the 3-yr study period, split-N + CC significantly reduced flow-weighted NO3–N concentration and NO3–N loss by 35 and 37%, respectively, compared with preplant-N. However, flow-weighted NO3–N concentration (4.3 mg L–1) and NO3–N loss (22.4 kg ha–1) with split-N were not significantly different from either preplant-N (4.8 mg L–1 and 26.4 kg ha–1, respectively) or split-N + CC (3.1 mg L–1 and 16.7 kg ha–1, respectively). Corn yield was significantly lower in the control treatment but did not differ among N fertilized treatments in any year. These results indicate that combining split-N application with cover crops holds promise for meeting the statewide interim milestone NO3–N reduction target of 15% by 2025 without negatively impacting crop productivity.
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U2 - 10.1002/jeq2.20283
DO - 10.1002/jeq2.20283
M3 - Article
C2 - 34390507
AN - SCOPUS:85115722435
SN - 0047-2425
VL - 50
SP - 1408
EP - 1418
JO - Journal of Environmental Quality
JF - Journal of Environmental Quality
IS - 6
ER -