Soil CO<inf>2</inf> emission and carbon budget of a wheat/maize annual double-cropped system in response to tillage and residue management in the North China Plain
Citation
Wu, L.F., Li, B.B., Qin, Y., Gregorich, E. (2017). Soil CO2 emission and carbon budget of a wheat/maize annual double-cropped system in response to tillage and residue management in the North China Plain. International Journal of Agricultural Sustainability, [online] 15(3), 253-263. http://dx.doi.org/10.1080/14735903.2017.1288518
Plain language summary
This study was conducted to investigate the effects of tillage and crop residue management on soil CO2 emissions and C budget in double-cropped systems. With double-cropping more C inputs enter the soil thereby affecting microbial activity and decomposition of residues. The wheat/maize double-cropped system in the resulted in greater benefits of increased C storage in soil with crop residues’ retention in the field than removal from the field under both conventional tillage and no-till; the no-till with residues returned also had the smallest CO2 emission.
Abstract
To investigate the impacts of tillage and crop residue managements on soil CO2 emission and C budget in a wheat (Triticum aestivum L.)/maize (Zea mays L.) double-cropped system in the North China Plain (NCP), a field experiment was conducted consisting of four treatments: tillage with crop residues retention (CT+), tillage with crop residues removal (CT−), no-till with crop residues retention (NT+), and no-till with crop residues removal (NT−). Daily soil CO2 fluxes changed with crop growing stage and peaked during the most vigorous growth of period, fluxes in maize season were higher than those in wheat season. Compared to the tilled soils, cumulative CO2 emissions were significantly lower under no-till treatments. The largest cumulative CO2 emission occurred under CT+ (65 g CO2-C m−2 y−1) and the smallest was under NT+ (39 g CO2-C m−2 y−1). After 5 years of the experiment, soil organic carbon (SOC) sequestration were greater with crop residues retention (CT+ and NT+) than with crop residues removal (CT− and NT−), the maximum SOC stock was in NT+ (5940 g C m−2) while the minimum was in CT− (3635 g C m−2). NT+ could help to mitigate CO2 emission in the annual wheat/maize double-cropping system of the area.