Long-term tillage and cover cropping differentially influenced soil nitrous oxide emissions from cotton cropping system

Climate-smart agricultural practices, such as no-tillage (NT) and cover cropping, have been widely adopted and are anticipated to yield multiple benefits, including soil carbon sequestration, enhancing soil health, and crop yield stability. However, their influence on nitrous oxide (N2O) emissions varies, with the potential of both increasing and decreasing N2O emissions. Increasing N2O emissions under these practices may potentially offset the climate mitigation benefits from increased soil carbon sequestration. We investigated N2O emissions in response to 42 years of long-term adoption of NT and legume cover crop, under nitrogen rates of 0 and 67 kg N ha-1, in a continuous cotton system in the Southeastern US. Intensive manual chamber-based measurements were conducted over two growing seasons (2021-2022 and 2022-2023). Long-term NT did not significantly (p > 0.05) affect cumulative N2O emissions during the study period. Hairy vetch cover crop-grown plots emitted 2-3 times more N2O ..., , , # Long-term Tillage and Cover Cropping Differentially Influenced Soil Nitrous Oxide Emissions from Cotton Cropping System

[https://doi.org/10.5061/dryad.0vt4b8h75](https://doi.org/10.5061/dryad.0vt4b8h75)

## Description of the data and file structure

This study aimed to evaluate the long-term impact of no-till (NT) practices and cover crops on nitrous oxide (N₂O) emissions in interaction with nitrogen (N) fertilization in a continuous cotton cropping system in the Southeast US. The experiment was designed using a split-split plot layout, with selected experimental levels including two N rates (0, NF; 67 kg N ha⁻¹, F), two cover crop treatments (hairy vetch, HV; no cover crop, NC) in the sub-plot, and two tillage methods (conventional tillage, CT; no-till, NT) in the sub-sub plot, replicated four times. N₂O emissions and soil data were collected from November 2021 to October 2023. Soil samples from a 0-10 cm depth were periodically collected and analyzed for ammonium (NH₄⁺), nitrate (...