No-till farming and greenhouse gas fluxes: Insights from literature and experimental data

Authors

S. J. Ruis, University of Nebraska - LincolnFollow
H. Blanco-Canqui, University of Nebraska - Lincoln
P. J. Jasa
V. L. Jin, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), University of Nebraska-Lincoln

Document Type

Article

Date of this Version

3-2-2022

Citation

S.J. Ruis et al. Soil & Tillage Research 220 (2022) 105359. https://doi.org/10.1016/j.still.2022.105359

Comments

© 2022 Elsevier B.V. All rights reserved.

Abstract

Tillage intensity may differently impact gaseous losses of C and N to the atmosphere, but data from long-term experiments are relatively few. Yet, this information is needed to better understand C and N losses and gains in agricultural systems. The objective of this study was to determine how tillage intensity affects soil greenhouse gas (GHG) fluxes (CO₂, N₂O, and CH₄) by comparing experimental data from moldboard plow (MP), chisel plow (CP), double disk (DD), and no-till (NT) soils after 38–40 yr of management in a rainfed corn (Zea mays L.)- soybean (Glycine max (L.) Merr) cropping system. We also reviewed global literature to evaluate the impacts of tillage on soil GHG emissions. After 38–40 yr of management, CO₂ fluxes decreased in this order: MP > CP ≈ DD > NT, indicating that as tillage intensity decreased, CO₂ fluxes decreased. Indeed, daily CO2 fluxes were typically lower under NT than under MP and CP. Similarly, the overall cumulative CO₂ fluxes across 26-mo of measurement were 1.4–1.8 times lower with NT than MP, CP, and DD soils. Also, MP soils had 1.3 times higher CO₂ fluxes than CP and DD soils. These results are similar to those from our global literature review of 60 studies on CO₂ fluxes. The reduction in CO₂ fluxes in NT was likely due to a combination of increased residue cover, reduced soil temperature (r = 0.71; n = 12; p < 0.001), and increased water content (r = 0.75; n = 12; p < 0.001). Daily N₂O and CH₄ fluxes were highly variable; and cumulative fluxes across the 26-mo study were unaffected by tillage, mirroring findings of our literature review of 37 papers on N₂O fluxes and 24 on CH₄ fluxes. Overall, based on the data from both the long-term experiment and literature review, NT appears to be the best option to reduce losses of CO₂ followed by reduced till (DD), but N₂O and CH₄ fluxes do not generally differ with tillage intensity.