Title: Does No–Tillage Mitigate Stover Removal in Irrigated Continuous Corn? A Multi–Location Assessment

Abstract

No-tillage (NT) may ameliorate negative effects on soil properties from corn (Zea mays L.) stover harvest, but few long-term irrigated continuous corn production systems have been evaluated to test this hypothesis. We evaluated three long-term no-tillage sites (4–13 yr) in Nebraska and Colorado that spanned a range of precipitation and soil organic carbon (SOC) levels. We measured SOC, δ¹³C of SOC, soil microbial biomass (SMB) and composition (i.e., phospholipid fatty acids, PLFAs), and water stable aggregation at all sites under stover retention vs. removal (~60%). Surface SOC stocks (0–30- cm depth) increased across the gradient and were 46.4, 57.4, and 63.1 Mg C ha^–1 for Colorado, central Nebraska, and eastern Nebraska, respectively. Overall, residue removal decreased SOC stocks by 6% and soil aggregation by 12% in the 0- to 30-cm depth. The δ¹³C signature of SOC indicated less new surface C storage under residue removal in Colorado, but not at the two Nebraska sites. Residue harvest did not decrease SMB or change soil microbial community structure, suggesting that high plant productivity buffered community composition from stover harvest impacts under NT but stimulated microbial activity levels that led to SOC loss. Here, the high rates of stover removal used in thismore » study decreased SOC stocks and aggregation at all sites compared to residue retained treatments, suggesting that no-tillage alone was not sufficient to maintain erosion protection and soil function.« less

Authors:

Stewart, Catherine E. ^[1]; Roosendaal, Damaris L. ^[1]; Sindelar, Aaron ^[2]; Pruessner, Elizabeth ^[1]; Jin, Virginia L. ^[3]; Schmer, Marty R. ^[3]

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+ Show Author Affiliations

1. US Dept. of Agriculture (USDA), Fort Collins, CO (United States). Agricultural Research Service (ARS)
2. BAYER U.S. Crop Science, Lincoln, NE (United States)
3. Univ. of Nebraska, Lincoln, NE (United States); US Dept. of Agriculture (USDA), Lincoln, NE (United States). Agricultural Research Service (ARS)

Publication Date:

Wed May 01 00:00:00 EDT 2019

Research Org.:

Antares Group Inc., Conyers, GA (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE), Transportation Office. Bioenergy Technologies Office

OSTI Identifier:

1853946

Report Number(s):

DOE-ANTARES-07088-2-3
Journal ID: ISSN 0361-5995

Grant/Contract Number:  

EE0007088

Resource Type:

Accepted Manuscript

Journal Name:

Soil Science Society of America Journal

Additional Journal Information:

Journal Volume: 83; Journal Issue: 3; Journal ID: ISSN 0361-5995

Publisher:

Alliance of Crop, Soil, and Environmental Science Societies

Country of Publication:

United States

Language:

English

Subject:

54 ENVIRONMENTAL SCIENCES