Response of soil carbon dioxide emissions to no-tillage and moldboard plow systems on Andosols in a humid, subtropical climate, Japan

Abstract Characterization of soil carbon dioxide (CO2) emissions can help us to understand the effects of agricultural management on climate change and the ability of soil to sequester atmospheric carbon. However, there is a lack of studies on the effects of tillage and cover crops on soil CO2 emissions on Andosols in the humid, subtropical climate. The present study aimed to quantify soil CO2 emissions and identify the factors accounting for CO2 emissions among no-tillage (NT) and moldboard plow (MP) systems under different cover crop treatments at an experimental site established in 2002 in Kanto, Japan. A split-plot field experiment was conducted from May 2017 to November 2018 comprising two tillage systems (NT and MP) and three cover crops: fallow, hairy vetch (HV), and rye (RY). Higher soil CO2 daily emissions at 80% of the measurements and significantly greater CO2 seasonal and annual emissions were observed in the NT system as compared to the MP system. The relationship between CO2 daily flux and soil temperature was well-described by exponential functions (p