Skip to main content
ARS Home » Plains Area » Lincoln, Nebraska » Agroecosystem Management Research » Research » Publications at this Location » Publication #414911

Research Project: Integrated Agricultural Systems for a Resilient Circular Bioeconomy in the Central Plains

Location: Agroecosystem Management Research

Title: Long-term tillage and residue removal effects on soil carbon, nitrogen, and grain yield in irrigated corn

Author
item SCHMER, MARTY
item RAMIREZ, SALVADOR
item JIN, VIRGINIA
item WEINHOLD, BRIAN - Retired ARS Employee
item Varvel, Gary
item WILHELM, WILLIAM - Retired ARS Employee

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/12/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary: The use of corn stover either as a forage for livestock or use as a bioenergy feedstock is expected to increase in the future. Limited information on how management affects the soil resource with mechanical harvesting of corn stover. Soil properties were collected from a 20-year experiment in eastern Nebraska. The continous corn experiment was under irrigation had different corn stover removal rates and tillage practices (no-till or disk tillage). After 20 years, grain yield was 5.8% to 6.0% greaterr under no-till with stover removal compared with no-till and no stover removal, while grain yield was similar for disk tillage in all stover removal treatments. High stover removal rates resulted in greater soil organic carbon loss at the surface soil layers (0-15 cm; 0-30 cm) after 20 years compared with no or medium stover removal. All management practices resulted in cumulative (0-120 cm) soil organic carbon stock loss that occurred in the last 10 years of the study. Aboveground and belowground C inputs were not adequate to maintain cumulative SOC stocks in this irrigated system. Further investigations are needed to understand processes of sub-surface soil organic carbon stock loss in current agricultural system practices.

Technical Abstract: Corn (Zea mays L.) stover demand as a forage or for an emerging bioeconomy has increased the importance of determining the long-term effects of stover removal on grain yield and the soil resource. Study objectives were to evaluate grain yield, soil organic carbon (SOC), and total soil N (0–150 cm) in a 20-yr, irrigated, continuous corn study, located in eastern Nebraska, under conventional disk tillage (CT) and no-till (NT) with variable corn stover removal rates (none, medium, and high). After 20 years, grain yield was 5.8% to 6.0% greater under NT with stover removal compared with NT and no stover removal, while grain yield was similar for CT in all stover removal treatments. Mean grain yield was similar between NT with stover removal and CT in all stover removal treatments. High stover removal rates resulted in greater SOC loss at the surface soil layers (0-15 cm; 0-30 cm) after 20 years compared with no or medium stover removal. Corn stover retention under NT resulted in the same cumulative SOC stock loss as CT or stover removal. All management practices resulted in cumulative (0-120 cm) SOC stock loss that occurred in the last 10 years of the study. Total soil nitrogen stocks were maintained or increased after 20 years at the surface soil layers (0-15 cm; 0-30 cm) and were similar between NT and CT. In an irrigated continuous corn system, neither NT nor stover retention was able to maintain cumulative SOC stocks over time.